Sibling Scientists Share in Rutgers-Robert Wood Johnson Partnership to Fight Chemical Warfare

 

Credit: Nick Romanenko
Debra Laskin, and her brother, Jeffrey, are co-investigators at the Environmental and Occupational Health Sciences Institute.

 

 

Target Health Inc. works closely with both Dr. Laskins in the CounterACT, NIH funded research program

 

 

Debra and Jeffrey Laskin say scientific research is their family business.  As kids, Jeffrey and Debra Laskin would work on science projects together. Later as graduate students they would talk about their future plans that always revolved around science. And for more than 25 years, the two, both trained in pharmacology and toxicology, have worked side by side on several National Institutes of Health funded research projects and more than 150 scientific articles and reviews.

Not a day goes by, they say, when they don’t see each other or talk on the phone. Earlier this month, the two shared in the announcement that the National Institutes of Health awarded Rutgers and UMDNJ-Robert Wood Johnson Medical Center a five-year, $23 million grant to to continue their research developing drugs that could be used against chemical warfare agents from a terrorist attack.

“It’s hard to develop as a scientist and be successful without collaborators,” says Debra Laskin, Professor II and Chair of Pharmacology and Toxicology at the Ernest Mario School of Pharmacy and the Roy A. Bowers Endowed Chair of Pharmacy. “This collaboration has really been productive because we trust each other. There is no jealousy or competition.”

The Laskins are part of a Rutgers-UMDNJ team that has won $42.4 million in grants to develop countermeasures to chemical threats from terrorism.

Maybe that’s because scientific research has always been the Laskin’s family business.

Father, Sidney Laskin, who died in 1976 when Debra Laskin was a graduate student, was a toxicological scientist on the faculty of New York University (NYU). He was passionate about his work, she says, and was an inspiration to his family.  At the beginning of his career, the elder Laskin worked on the Manhattan Project, the United States led research effort that produced the first atomic bomb during World War II. Before he died, he invented systems for inhalation toxicology studies, some of which are still being used today.

While Debra Laskin, at first, thought she wanted to become a psychologist and earned a bachelor’s and master’s degree in psychology at NYU and the City University of New York, it wasn’t until after her father’s death, while a graduate student in pharmacology and toxicology at the Medical College of Virginia, that she found her true calling.  She would follow in her father’s footsteps and become a toxicological scientist.

Jeffrey Laskin, a professor of Environmental and Occupational Medicine at the University of Medicine and Dentistry of New Jersey (UMDNJ)-Robert Wood Johnson Medical School and three years older, earned an undergraduate degree in chemistry and biology at NYU, and a doctorate in Pharmacology at Roswell Park Cancer Institute at SUNY in Buffalo.  He was finishing up post-doctorate work at Columbia University in carcinogenesis and getting ready to start his research career in toxicology, pharmacology and cancer research when his sister decided to enter the family business.

And although brother, Steven, did not choose the same exact career path as his siblings, he, too, was drawn to the sciences, earning both a medical degree and a doctorate at NYU and specializing in neurology.

Their mother Laura, an antiques dealer in Somerville, says her husband would have been thrilled that they followed his footsteps into scientific research.

“All three of us had the same biology professor at NYU over the course of six years,” said Debra Laskin, “I tell people that Steven took copious notes, Jeff filled in the notes and I filled in the jokes.”

Both Laskins have been in their academic positions since the 1980s, Jeffrey at UMDNJ-Robert Wood Johnson Medical School and Debra at Rutgers Ernest Mario School of Pharmacy. Jeffrey started when programs in environmental sciences, toxicology and occupational medicine were being established at UMDNJ-Robert Wood Johnson Medical School and Debra began a few years later when Rutgers was starting a new joint graduate program in toxicology.

It was a time, they say, when the field was exploding with possibilities and they were both involved in a career choice that seemed to be part of their genetic make-up.

Today, as members of the Rutgers/UMDNJ-Robert Wood Johnson Medical School, Environmental and Occupational Health Sciences Institute (EOHSI), the two are part of a team racing to develop not only the pharmaceuticals needed to save the lives of people who could become targets in a terrorist attack, but also to devise the best methods for these drugs to be delivered.

The NIH $23.2 million grant awarded to Rutgers/UMDNJ-Robert Wood Johnson Medical School, as well as the School of Public Health at New York Medical College, and the Health Sciences Program at Lehigh University — all part of the CounterACT Center of Excellence — will be used to develop drugs that could treat deadly, chemical poisons, such as mustard gas, which causes symptoms ranging from skin irritations and conjunctivitis to severe ulcerations, blistering of the skin, blindness and irreversible damage to the respiratory system.

“We understand that just because Osama bin Laden was killed, the threat of a terrorist attack is not over,” said Jeffrey Laskin.  “We have made progress and believe that the drugs needed in case of a terrorist attack will be developed.”

 

 

ScienceDaily.com, October 4, 2011  —  The immune response to an H5N1 avian influenza vaccine was greatly enhanced in healthy adults if they were first primed with a DNA vaccine expressing a gene for a key H5N1 protein, researchers say. Their report describes results from two clinical studies conducted by researchers from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.

 

A majority of study volunteers who received the DNA vaccine 24 weeks before receiving a booster vaccine made from whole, inactivated H5N1 virus produced high levels of antibodies thought to be protective against the globular head region of a protein called hemagglutinin (HA). Traditional seasonal influenza vaccines are designed to elicit antibodies to the head region of HA, but it changes each year and so vaccines must be repeated annually to maintain immunity. In some volunteers, the prime-boost vaccine regimen also spurred production of broadly neutralizing antibodies aimed at the HA stem, a region that is relatively constant across many strains of influenza viruses.

 

“The results of these studies demonstrate an important proof of concept, in that it is possible to elicit broadly neutralizing influenza antibodies in humans through vaccination,” said NIAID Director Anthony S. Fauci, M.D. “These findings mark an early but significant milestone on the pathway to a universal influenza vaccine that provides protection against multiple virus strains.”

 

The findings from the Phase I clinical trials appear in an article online Oct. 4 in The Lancet Infectious Diseases. Gary J. Nabel, M.D., Ph.D., director of the NIAID Vaccine Research Center (VRC), and his colleagues developed the H5N1 influenza DNA vaccine. The other vaccine used in the study was made by Sanofi Pasteur, located in Swiftwater, Pa.

 

In 2010, VRC studies in mice, ferrets and monkeys showed that a DNA prime-boost influenza vaccine regimen can elicit broadly neutralizing antibodies directed against the HA stem. “Now we see that it is possible to elicit HA stem-directed antibodies in people as well,” said Dr. Nabel. The VRC researchers are hoping to apply this approach to research on vaccines against other seasonal and pandemic influenza strains too.

 

Since 2003, there have been 564 confirmed cases of human H5N1 influenza infection and 330 associated deaths worldwide, according to the most recent figures from the World Health Organization. Developing an effective vaccine against H5N1 influenza has proved difficult, because vaccines containing the whole, inactivated virus often fail to generate high levels of protective antibodies in people. The VRC studies confirm that volunteers who received only two doses of an inactivated H5N1 virus vaccine spaced 24 weeks apart produced only modest levels of H5N1-directed antibodies.

 

“Our study was designed to test whether a gene-based DNA vaccine could prime the immune system and lead to a better antibody response following boosting with an inactivated H5N1 vaccine,” said, Julie Ledgerwood, D.O., co-lead author of the new report and the study’s principal investigator, of the VRC Clinical Trials Core. “We found that the DNA primer vaccine improved the response to the inactivated H5N1 vaccine, but only when the boost interval was increased to 24 weeks.”

 

Of the 26 volunteers who received the vaccines 24 weeks apart, 21 produced antibodies at levels predicted to protect them from H5N1 influenza. The antibody levels in that group were more than four times higher than those seen in volunteers who received two doses of inactivated H5N1 virus vaccine. Among volunteers who received their booster vaccine just four weeks after the DNA prime, only 4 out of 15 produced protective levels of antibodies.

In both clinical studies, the H5N1 DNA priming vaccine was found to be safe. That finding is consistent with data from previous clinical trials in which VRC DNA vaccines for HIV, Ebola, Marburg, West Nile virus, SARS and seasonal influenza have been tested and found to be safe in a total of 2,100 volunteers.

Next, the team will try to improve its DNA and other gene-based vaccines to more readily elicit antibodies directed at the stem region of the HA protein. The VRC group also is planning a larger trial of a prime-boost vaccine for seasonal influenza.

 

Journal References:

  1. JE Ledgerwood et al. DNA priming and influenza vaccine immunogenicity: two phase 1 open label randomized clinical trials. The Lancet Infectious Diseases, 2011 DOI: 10.1016/S1473-3099(11)70240-7
  2. C.-J. Wei, J. C. Boyington, P. M. McTamney, W.-P. Kong, M. B. Pearce, L. Xu, H. Andersen, S. Rao, T. M. Tumpey, Z.-Y. Yang, G. J. Nabel. Induction of Broadly Neutralizing H1N1 Influenza Antibodies by Vaccination. Science, 2010; 329 (5995): 1060 DOI: 10.1126/science.1192517

 

DNA Vaccines

 

Genetic/ DNA immunization is a novel technique used to efficiently stimulate humoral and cellular immune responses to protein antigens. The direct injection of genetic material into a living host causes a small amount of its cells to produce the introduced gene products. This inappropriate gene expression within the host has important immunological consequences, resulting in the specific immune activation of the host against the gene delivered antigen (Koprowski et al, 1998).

Traditional Vaccines: The development of vaccination against harmful pathogenic microorganisms represents an important advancement in the history of modern medicine. In the past, traditional vaccination has relied on two specific types of microbiological preparations to produce material for immunization and generation of a protective immune response. These two categories involve either living infectious material that has been manufactured in a weaker state and therefore inhibits the vaccine from causing disease, or inert, inactivated, or subunit preparations.

Live attenuated vaccines stimulate protective immune responses when they replicate in the host. The viral proteins produced within the host are released into the extracellular space surrounding the infected cells and are then acquired, internalized and digested by scavenger cells that circulate the body. These cells are called antigen presenting cells (APCs) and include macrophages, dendritic cells, and B cells, which work together to expand immune response. The APCs recirculate fragments of the digested the antigen to their surface, attached to MHC class II antigens. This complex of foreign peptide antigen plus host MHC class II antigens forms part of
the specific signal with which APCs along with the MHC peptide complex, trigger the action of of immune cells, the T helper lymphocytes. The second part of the activation signal comes from the APCs themselves, which display on their cell surface constimulatory molecules along with MHC-antigen complexes. Both drive T call expansion and activation through interaction with their respective ligands, the T cell receptor complex (TCR) and the constimulatory receptors CD28/CTLA4, present on the the T cell surface. Activated T cells secrete molecules that act as powerful activates of immune cells. Also as viral proteins are produced within the host cells, small parts of these proteins surface, chaperoned by host cell MHC class I antigens.

These complexes together are recognized by a second class of T cells, killer or cytotoxic cells. This recognition, along with other stimulation by APCs and production of cytokine by stimulated T cells, is responsible for the developments of mature cytotoxic T cells (CTL) capable of destroying infected cells. In most instances live infection induces life long immunity. Although live attenuated preparations are the vaccines of choice they do pose the risk of reversion to their pathogenic form, causing infection.

 

Immune Response

In contrast, when inoculated nonlive vaccines composed of whole or even partial viruses are not produced within the host cells, they mainly end up in the extracellular space.  They provide protection by directly generating T helper and humoral immune responses against the pathogenic immunogen. In the absence of the cellular production of the foreign antigen, these vaccines are usually devoid of the ability to induce significant T cytotoxic responses. In addition, these vaccines are not actually produced in the host, and therefore, they are not customized by the host. The immunity induced by their vaccines frequently decreases during the life of the host and may require additional boosters to achieve lifelong immunity. However, nonlive vaccines offer some important advantages over live vaccines: they are produced earlier, and they can be designed to contain only the specific antigenic target of the pathogen that is involved in the development of protective immunity and exclude all other viral components.


Genetic Immunization: Since its early applications in the 1950’s, DNA-based immunization has become a novel approach to vaccine
development. Direct injection of naked plasmid DNA induces strong immune responses to the antigen encoded by the gene vaccine. Once the plasmid DNA construct is injected the host cells take up the foreign DNA, expressing the viral gene and producng the corresponding viral protein inside the cell. This form of antigen presentation and processing induced both MHC and class I and class II restricted cellular and humoral immune responses (Encke, J. et al, 1999).

  • History: The use of genetic material to deliver genes for therapeutic purposes has been practiced for many years. Experiments outlining the transfer of DNA into cells of living animals were reported as early as 1950. Later experiments using purified genetic material only further confirmed that the direct DNA gene injection in the absence of viral vectors results in the expression of the inoculated genes in the host. There have been additional experiments that extend these findings to recombinant DNA molecules, further illustrating the idea that purified nucleic acids could be directly delivered into a host and proteins would be produced. In 1992, scientists Tang and Johnson reported that the delivery of human growth hormone in a expression cassette in vivo resulted in production of detectable levels of the growth hormone in host mice. They also found that these inoculated mice developed antibodies against the human growth hormone; they termed this immunization procedure “genetic immunization”, which describes the ability of inoculated genes to be individual immunogens (Koprowski et al, 1998).

DNA Vaccines

  • Construction:  DNA vaccines are composed of a bacterial plasmids. Expression plasmids used in DNA-based vaccination normally contain two unites: the antigen expression unit composed of promoter/enhancer sequences, followed by antigen-encoding and polyadenylation sequences and the production unit composed of of bacterial sequences necessary for plamid amplification and selection (Schirmbeck, R., 2001). The construction of bacterial plasmids with vaccine inserts is accomplished using recombinant DNA technology.  Once constructed, the vaccine plasmid is transformed into bacteria, where bacterial growth produces multiple plasmid copies. The plasmid DNA is then purified from the bacteria, by separating the circular plasmid from the much larger bacterial DNA and other bacterial impurities. This purifies DNA acts as the vaccine (AAM, 1996).

DNA vaccine plasmid

  • Administration- Over the past decade of clinical research and trials, several possible routs of plasmid delivery have been found. Successful immunization has been demonstrated after delivery of plasmids through intramuscular, intradermal and intravenous injection. The skin and mucous membranes being considered the best site for immunization due to the high concentrations of dendritic cells (DC), macrophages and lymphocytes (Raz,E., 1998). Intradermal injection of DNA-coated gold particles with a gene gun have been used. The plasmid DNA can be diluted in distilled water, saline or sucrose. There has also been positive demonstration of proinjection or codelivery with various drugs (Encke et al, 1999).
  • Mechanisms: A plasmid vector that expresses the protein of interest (e.g. viral protein) under the control of an appropriate promoter is injected into the skin or muscle of the the host. After uptake of the plasmid, the protein is produced endogenously and intracellularly processed into small antigenic peptides by the host proteases. The peptides then enter the lumen of the endoplasmic reticulum (E.R.) by membrane-associated transporters. In the E.R., peptides bind to MHC class I molecules.  These peptides are presented on the cell surface in the context of the MHC class I. Subsequent CD8+ cytotoxic T cells (CTL) are stimulated and they evoke cell-mediated immunity. CTLs inhibit viruses through both cytolysis of infected cells and noncytolysis mechanisms such as cytokine production (Encke et al, 1999).
    The foreign protein can also be presented by the MHC class II pathway by APCs which elicit helper T cells (CD4+) responses. These CD4+ cells are able to recognize the peptides formed from exogenous proteins that were endocytosed or phagocytosed by APC, then degraded to peptide fragments and loaded onto MHC class II molecules. Depending on the the type of CD4+ cell that binds to the complex, B cells are stimulated and antibody production is stimulated. This is the same manner in which traditional vaccines work (Schirmbeck et al., 2001).
  • Advantages: DNA immunization offers many advantages over the traditional forms of vaccination. It is able to induce the expression of antigens that resemble native viral epitopes more closely than standard vaccines do since live attenuated and killed vaccines are often altered in their protein structure and antigenicity. Plasmid vectors can be constructed and produced quickly  and the coding sequence can be manipulated in many ways. DNA vaccines encoding several antigens or proteins can be delivered to the host in a single dose, only requiring a microgram of plasmids to induce immune responses. Rapid and large-scale production are available at costs considerably lower than traditional vaccines, and they are also very temperature stable making storage and transport much easier. Another important advantage of genetic vaccines is their therapeutic potential for ongoing chronic viral infections.  DNA vaccination may provide an important tool for stimulating an immune response in HBV, HCV and HIV patients. The continuos expression of the viral antigen caused by gene vaccination in an environment containing many APCs may promote successful therapeutic immune response which cannot be obtained by other traditional vaccines (Encke et al, 1999). This is a subject that has generated a lot of interest in the last five years.
  • Limitations: Although DNA can be used to raise immune responses against pathogenic proteins, certain microbes have outer capsids that are made up of polysaccharides.  This limits the extent of the usage of DNA vaccines because they cannot substitute for polysaccharide-based subunit vaccines (AMM, 1996).
  • Future- It has recently been discovered that the transfection of myocytes can be amplified by pretreatment with local anesthetics or with cardiotoxin, which induce local tissue damage and initiate myoblast regeneration. Gaining a full understanding of this mechanism of DNA uptake could prove helpful in improving applications for gene therapy and gene vaccination. Both improved expression and better engineering of the DNA plasmid may enhance antibody response to the gene products and expand the applications of the gene vaccines

Nanotherapeutics’ GelVac™ Nasal Dry-Powder H5N1 Influenza Vaccine Shown to Be Safe in Early Stage Clinical Trial

 

Alachua, Florida (PRWEB) October 03, 2011

Nanotherapeutics, Inc. announced the successful completion of a Phase 1 clinical trial of GelVac™ Nasal Dry-Powder H5N1 Influenza Vaccine. The trial assessed the safety of the novel intranasal dry-powder formulation vaccine for the H5N1 flu strain. No safety issues were identified, and no serious adverse events occurred during the trial. The vaccine, which was administered intranasally by a disposable single-use inhaler, was well tolerated by the patients. GelVac™ incorporates the GelSite® polymer, combining it with an H5N1 antigen.

 

Patients received two intranasal doses given 4 weeks apart. Nasal wash and serum samples were collected at several time points for exploratory endpoints of effectiveness. Although the study was not statistically powered to provide effectiveness data, initial results are encouraging and support the development of larger trials to confirm efficacy and demonstrate distinct advantages in meeting the critical needs of pandemic preparedness. The preliminary data show increased serum and mucosal IgA as well as serum HAI responses to H5N1.

 

The GelVac™ vaccine possesses distinct potential advantages, including induction of both mucosal and systemic immunity, room temperature stability, prolonged shelf life, cold-chain-free distribution, and needle-free administration that can be particularly valuable in meeting the needs for pandemic preparation and stockpiling.

 

GelSite® polymer is a novel, naturally occurring, mucoadhesive ionic carbohydrate polymer capable of forming a gel when brought into contact with nasal fluids. Gelling occurs with the powder formulation and provides sustained antigen release within the nasal cavity for enhancement of the immune response.

 

About GelVac™ Nasal Dry-Powder H5N1 Influenza Vaccine

GelVac™ Nasal Dry-Powder H5N1 Influenza Vaccine is a powder vaccine that has been formulated using an inactivated cell-based influenza H5N1 whole virion antigen in combination with GelSite® polymer, a novel plant polysaccharide with gelling properties to encapsulate vaccine/adjuvant formulation as gel particles. The powder vaccine formulation is filled into a positive pressure nasal delivery device and delivered into the nasal cavity by compressed air.

 

GelVac™ Nasal Dry-Powder H5N1 Influenza Vaccine with GelSite® Polymer offers distinctive chemical and functional properties. The vaccine provides important advantages for the pandemic preparedness, including room temperature stability, needle-free administration, and induction of both mucosal and systemic immune responses.

About the GelSite® Polymer Platform

 

GelSite® Polymer is a chemically and functionally distinct high molecular weight anionic polysaccharide extracted from Aloe vera L., a succulent plant widely cultivated in the tropical and subtropical regions and is general considered as safe (GRAS). GelSite® Polymer has been shown to have an adjuvant-like effect increasing immune response and antigen sparing when administered together with the antigen by intramuscular injection. GelSite® Polymer is inert and the polymer gel does not support cell adhesion. This adjuvant effect can be obtained at a very low polymer concentration, lower than that of the alum adjuvant commonly used in licensed vaccines. GelSite® Polymer has been tested in various vaccine formulations for administration by the nasal route and injection and can serve as a platform technology due to its distinctive chemical and functional properties.

 

About Nanotherapeutics
Nanotherapeutics, Inc. is a privately held biopharmaceutical company with a major focus on developing a diversified proprietary pipeline of products having both biodefense and medical applications. Products under development include biodefense, CNS, wound healing, addiction and pain, oncology, anti-infectives and orthopedics. The Company has one FDA-approved injectable biologic NanoFUSE® DBM used by orthopedic surgeons as bone graft filler. Nanotherapeutics has in-house cGMP manufacturing, formulation, and expertise in pre-clinical and clinical product development as well as clinical trial management to support its products. Established ten years ago, the Company employs several proprietary platform technologies to manipulate and enhance the properties of drug candidates. For more information, visit the Company website at http://www.nanotherapeutics.com.

Media contact:
Gary A. Ascani
386-462-9663
Nanotherapeutics, Inc.
VP, Business Development
gascani(at)nanotherapeutics(dot)com

Light photomicrograph of brain tissue reveals the presence of typical amyloid plaques found in a case of variant Creutzfeldt-Jakob disease (vCJD), a prion disease. (Credit: Sherif Zaki; MD; PhD; Wun-Ju Shieh; MD; PhD; MPH / via CDC Public Health Images Library)

 

 

 

Univ of Texas at Houston, October 4, 2011, (HOUSTON) — The brain damage that characterizes Alzheimer’s disease may originate in a form similar to that of infectious prion diseases such as bovine spongiform encephalopathy (mad cow) and Creutzfeldt-Jakob, according to newly published research by The University of Texas Health Science Center at Houston (UTHealth).

 

 

“Our findings open the possibility that some of the sporadic Alzheimer’s cases may arise from an infectious process, which occurs with other neurological diseases such as mad cow and its human form, Creutzfeldt-Jakob disease,” said Claudio Soto, Ph.D., professor of neurology at The University of Texas Medical School at Houston, part of UTHealth. “The underlying mechanism of Alzheimer’s disease is very similar to the prion diseases. It involves a normal protein that becomes misshapen and is able to spread by transforming good proteins to bad ones. The bad proteins accumulate in the brain, forming plaque deposits that are believed to kill neuron cells in Alzheimer’s.”

 

The results showing a potentially infectious spreading of Alzheimer’s disease in animal models were published in the Oct. 4, 2011 online issue of Molecular Psychiatry, part of the Nature Publishing Group. The research was funded by The George P. and Cynthia W. Mitchell Center for Research in Alzheimer’s Disease and Related Brain Disorders at UTHealth.

Alzheimer’s disease is a form of progressive dementia that affects memory, thinking and behavior. Of the estimated 5.4 million cases of Alzheimer’s in the United States, 90 percent are sporadic. The plaques caused by misshapen aggregates of beta amyloid protein, along with twisted fibers of the protein tau, are the two major hallmarks associated with the disease. Alzheimer’s is the sixth leading cause of death in the United States, according to the Alzheimer’s Association.

 

Researchers injected the brain tissue of a confirmed Alzheimer’s patient into mice and compared the results to those from injected tissue of a control without the disease. None of the mice injected with the control showed signs of Alzheimer’s, whereas all of those injected with Alzheimer’s brain extracts developed plaques and other brain alterations typical of the disease.

 

“We took a normal mouse model that spontaneously does not develop any brain damage and injected a small amount of Alzheimer’s human brain tissue into the animal’s brain,” said Soto, who is director of the Mitchell Center. “The mouse developed Alzheimer’s over time and it spread to other portions of the brain. We are currently working on whether disease transmission can happen in real life under more natural routes of exposure.”

 

UTHealth co-authors of the paper are Rodrigo Morales, Ph.D, postdoctoral fellow, and Claudia Duran-Aniotz, research assistant. Other co-authors are Joaquin Castilla, Ph.D., Basque Foundation for Science, Bilbao, Spain; and Lisbell D. Estrada, Ph.D., Universidad Catolica de Chile, Santiago, Chile. Duran-Anoitz is also a doctoral student at the Universidad de los Andes in Santiago, Chile. Soto, Morales, Castilla and Estrada did a portion of the research at The University of Texas Medical Branch at Galveston.

The ePetri platform is built from Lego blocks and uses a smartphone as a light source. The imaging chip is seen in detail on the right. (Credit: Image courtesy of Guoan Zheng, California Institute of Technology)

 

 

 

PNAS, October 4, 2011  —  The cameras in our cell phones have dramatically changed the way we share the special moments in our lives, making photographs instantly available to friends and family. Now, the imaging sensor chips that form the heart of these built-in cameras are helping engineers at the California Institute of Technology (Caltech) transform the way cell cultures are imaged by serving as the platform for a “smart” petri dish.

Dubbed ePetri, the device is described in a paper that appears online this week in the Proceedings of the National Academy of Sciences (PNAS).

Since the late 1800s, biologists have used petri dishes primarily to grow cells. In the medical field, they are used to identify bacterial infections, such as tuberculosis. Conventional use of a petri dish requires that the cells being cultured be placed in an incubator to grow. As the sample grows, it is removed — often numerous times — from the incubator to be studied under a microscope.

Not so with the ePetri, whose platform does away with the need for bulky microscopes and significantly reduces human labor time, while improving the way in which the culture growth can be recorded.

“Our ePetri dish is a compact, small, lens-free microscopy imaging platform. We can directly track the cell culture or bacteria culture within the incubator,” explains Guoan Zheng, lead author of the study and a graduate student in electrical engineering at Caltech. “The data from the ePetri dish automatically transfers to a computer outside the incubator by a cable connection. Therefore, this technology can significantly streamline and improve cell culture experiments by cutting down on human labor and contamination risks.”

The team built the platform prototype using a Google smart phone, a commercially available cell-phone image sensor, and Lego building blocks. The culture is placed on the image-sensor chip, while the phone’s LED screen is used as a scanning light source. The device is placed in an incubator with a wire running from the chip to a laptop outside the incubator. As the image sensor takes pictures of the culture, that information is sent out to the laptop, enabling the researchers to acquire and save images of the cells as they are growing in real time. The technology is particularly adept at imaging confluent cells — those that grow very close to one another and typically cover the entire petri dish.

“Until now, imaging of confluent cell cultures has been a highly labor-intensive process in which the traditional microscope has to serve as an expensive and suboptimal workhorse,” says Changhuei Yang, senior author of the study and professor of electrical engineering and bioengineering at Caltech. “What this technology allows us to do is create a system in which you can do wide field-of-view microscopy imaging of confluent cell samples. It capitalizes on the use of readily available image-sensor technology, which is found in all cell-phone cameras.”

In addition to simplifying medical diagnostic tests, the ePetri platform may be useful in various other areas, such as drug screening and the detection of toxic compounds. It has also proved to be practical for use in basic research.

Caltech biologist Michael Elowitz, a coauthor on the study, has put the ePetri system to the test, using it to observe embryonic stem cells. Stem cells in different parts of a petri dish often behave differently, changing into various types of other, more specialized cells. Using a conventional microscope with its lens’s limitations, a researcher effectively wears blinders and is only able to focus on one region of the petri dish at a time, says Elowitz. But by using the ePetri platform, Elowitz was able to follow the stem-cell changes over the entire surface of the device.

“It radically reconceives the whole idea of what a light microscope is,” says Elowitz, a professor of biology and bioengineering at Caltech and a Howard Hughes Medical Institute investigator. “Instead of a large, heavy instrument full of delicate lenses, Yang and his team have invented a compact lightweight microscope with no lens at all, yet one that can still produce high-resolution images of living cells. Not only that, it can do so dynamically, following events over time in live cells, and across a wide range of spatial scales from the subcellular to the macroscopic.”

Elowitz says the technology can capture things that would otherwise be difficult or impossible — even with state-of-the-art light microscopes that are both much more complicated and much more expensive.

“With ePetri, you can survey the entire field at once, but still maintain the ability to ‘zoom in’ to any cells of interest,” he says. “In this regard, perhaps it’s a bit like an episode of CSI where they zoom in on what would otherwise be unresolvable details in a photograph.”

Yang and his team believe the ePetri system is likely to open up a whole range of new approaches to many other biological systems as well. Since it is a platform technology, it can be applied to other devices. For example, ePetri could provide microscopy-imaging capabilities for other portable diagnostic lab-on-a-chip tools. The team is also working to build a self-contained system that would include its own small incubator. This advance would make the system more useful as a desktop diagnostic tool that could be housed in a doctor’s office, reducing the need to send bacteria samples out to a lab for testing.

Funding support was provided by the Coulter Foundation.

Climate activists “sunbathe” on the edge of a frozen fjord in the Norwegian Arctic town of Longyearbyen April 25, 2007. REUTERS/Francois Lenoir

 


SINGAPORE, October 4, 2011, GoogleNews.com, ScienceDaily.com — A huge hole that appeared in the Earth’s protective ozone layer above the Arctic in 2011 was the largest recorded in the Northern Hemisphere, triggering worries the event could occur again and be even worse, scientists said in a report on Monday.

 

The ozone layer high in the stratosphere acts like a giant shield against the Sun’s ultraviolet (UV) radiation, which can cause skin cancers and cataracts.

 

Since the 1980s, scientists have recorded an ozone hole every summer above the Antarctic at the bottom of the globe.

Some years, the holes have been so large they covered the entire continent and stretched to parts of South America, leading to worries about a surge in skin cancers.

 

During extreme events, up to 70 percent of the ozone layer can be destroyed, before it recovers months later.

 

A matching hole above the Arctic was always much smaller, until March this year, when a combination of powerful wind patterns and intense cold high in the atmosphere created the right conditions for ozone-eating chlorine chemicals to damage the layer.

 

The findings, reported on Monday in the journal Nature, show the hole opened over northern Russia, parts of Greenland, and Norway, meaning people in these areas were likely to have been exposed to high levels of UV radiation.

 

“The chemical ozone destruction over the Arctic in early 2011 was, for the first time in the observational record, comparable to that in the Antarctic ozone hole,” say the scientists, led by Gloria Manney of the Jet Propulsion Laboratory in Pasadena, California.

 

MAN-MADE CHEMICALS

 

Scientists say man-made chemicals such as chlorofluorocarbons destroy ozone in the stratosphere. Sunlight breaks up the complex chemicals into simpler forms that react with ozone. While some of the chemicals are covered by a U.N. treaty that aims to stop their use, it will be decades before they are fully phased out of production.

 

Normally, atmospheric conditions high above the Arctic do not trigger a large-scale plunge in ozone levels. But in the 2010/11 winter, a high-altitude wind pattern called the polar vortex was unusually strong, leading to very cold conditions in the stratosphere that also lasted for several months.

 

This created the right conditions for the ozone-destroying forms of chlorine to slash ozone levels over a long period.

 

“Chemical ozone destruction in the 2011 Arctic polar vortex attained, for the first time, a level clearly identifiable as an Arctic ozone hole,” said the authors.

 

The researchers pointed to the risk if the Arctic hole becomes an annual event and spreads.

 

“More acute Arctic ozone destruction could exacerbate biological risks from increased ultraviolet radiation exposure, especially if the vortex shifted over densely populated mid-latitudes, as it did in April 2011,” they wrote.

(Reporting by David Fogarty; Editing by Daniel Magnowski)

These are images of a sugar crystal taken through polarized light filters. Left: traditional microscope. Right: cell phone microscope. (Credit: Z. J. Smith, K. Chu, A. R. Espenson, M. Rahimzadeh, A. Gryshuk, M. Molinaro, D. M. Dwyre, S. Lane, D. Matthews, S. Wachsmann-Hogiu.)

 

 

 

UCDavis, October 4, 2011  —  In a feat of technology tweaking that would rival MacGyver, a team of researchers from the University of California, Davis has transformed everyday iPhones into medical-quality imaging and chemical detection devices. With materials that cost about as much as a typical app, the decked-out smartphones are able to use their heightened senses to perform detailed microscopy and spectroscopy. The team will present their findings at the Optical Society’s (OSA) Annual Meeting, Frontiers in Optics (FiO) 2011, taking place in San Jose, Calif. Oct. 16-20.

The enhanced iPhones could help doctors and nurses diagnose blood diseases in developing nations where many hospitals and rural clinics have limited or no access to laboratory equipment. In addition to bringing new sensing capabilities where they are needed most, the modified phones are also able transmit the real-time data to colleagues around the globe for further analysis and diagnosis.

“Field workers could put a blood sample on a slide, take a picture, and send it to specialists to analyze,” says Sebastian Wachsmann-Hogiu, a physicist with UC Davis’ Department of Pathology and Laboratory Medicine and the Center for Biophotonics, Science and Technology, and lead author of the research to be presented at FiO.

Microscope Makeover

The group is not the first to build a smartphone microscope. “But we thought we could make something simpler and less expensive,” Wachsmann-Hogiu says.

His first attempt took simplicity too far. “We started with a drop of water on the camera’s lens,” he says. “The water formed a meniscus, and its curved surface acted like a magnifying lens. It worked fine, but the water evaporated too fast.”

Then the team turned to ball lenses. These are finely ground glass spheres that act as low-powered magnifying glasses. The team used a 1-millimeter-diameter ball lens that costs $30-40 USD in their prototype, but mass-produced lenses could be substituted to reduce the price.

To build the microscope’s lens, Kaiqin Chu, a post-doctoral researcher in optics, inserted a ball lens into a hole in a rubber sheet, then simply taped the sheet over the smartphone’s camera.

At 5x magnification, the ball lens is no more powerful than a child’s magnifying glass. Yet when paired with the camera of a smartphone, the microscope could resolve features on the order of 1.5 microns, small enough to identify different types of blood cells.

There are two reasons why such low magnification produces such high-resolution images. First, ball lenses excel at gathering light, which determines resolution. Second, the camera’s semiconductor sensor consists of millions of light-capturing cells. Each cell is only about 1.7 microns across. This is small enough to capture precisely the tiny high-resolution image that comes through the ball lens.

Ball lenses pose some unique problems. The curvature of their sphere bends light as it enters the ball, distorting the image, except for a very small spot in the center. The researchers used digital image processing software to correct for this distortion. They also used the software to stitch together overlapping photos of the tiny in-focus areas into a single image large enough for analysis.

Even though smartphone micrographs are not as sharp as those from laboratory microscopes, they are able to reveal important medical information, such as the reduced number and increased variation of cells in iron deficiency anemia, and the banana-shaped red blood cells characteristic of sickle cell anemia.

Wachsmann-Hogiu’s team is working with UC Davis Medical Center to validate the device and determine how to use it in the field. They may also add features, such as larger lenses to diagnose skin diseases and software to count and classify blood cells automatically in order to provide instant feedback and perhaps recognize a wider range of diseases.

Simple Spectrometer

When researchers need additional diagnostic tools, the microscope could be swapped for a simple spectrometer that also uses light collected by the iPhone’s camera.

Spectrometers smear out light from an object, separating it into its composite wavelengths in much the way a prism breaks up white light in the familiar colors of the rainbow. Since atoms and molecules absorb very specific wavelengths when exposed to light, it is possible to tease out the chemical signature of materials by studying their spectra.

Like the microscope, the iPhone’s spectrometer takes advantage of smartphone imaging capabilities. “We had worked with spectrometers for diagnostics, and didn’t think it would be too far a stretch,” Wachsmann-Hogiu says.

The spectrometer that the researchers added to the iPhone is easy to build. It starts with a short plastic tube covered at both ends with black electrical tape. Narrow slits cut into the tape allow only roughly parallel beams of light from the sample to enter and exit the tube. It is this grating that smears, or spreads, the light into a spectrum of colors that scientists can use like a fingerprint to identify various molecules.

“If you didn’t have the slits, light would come in from all different angles and you could never separate it properly,” explains Zachary Smith, an optics post-doctoral researcher in the lab.

Though the spectrometer is still in its early stages, the researchers believe it could measure the amount of oxygen in the blood and help diagnose chemical markers of disease.

Because smartphone instruments are powerful and cheap, Wachsmann-Hogiu believes schools could use them to enrich science classes. Spectrometers could help illustrate lessons about light and energy. Microscopes could unveil an invisible world of sugar crystals, pollen grains, and microscopic organisms.

By intelligently exploiting smartphone features, Wachsmann-Hogiu’s group promises to both save lives and illuminate science.

Researchers (from left) Shin-ichiro Imai, MD, PhD, Jun Yoshino, MD, PhD, and Kathryn Mills showed that a natural compound, NMN, helps to treat symptoms of diabetes in mice. (Credit: Julia Evangelou Strait)

 

 

 

Washington U. School of Medicine, October 4, 2011,  (ST. LOUIS) — Researchers at Washington University School of Medicine in St. Louis have restored normal blood sugar metabolism in diabetic mice using a compound the body makes naturally. The finding suggests that it may one day be possible for people to take the compound much like a daily vitamin as a way to treat or even prevent type 2 diabetes.

This naturally occurring compound is called nicotinamide mononucleotide, or NMN, and it plays a vital role in how cells use energy.

“After giving NMN, glucose tolerance goes completely back to normal in female diabetic mice,” says Shin-ichiro Imai, MD, PhD, associate professor of developmental biology. “In males, we see a milder effect compared to females, but we still see an effect. These are really remarkable results. NMN improves diabetic symptoms, at least in mice.”

The research appears online Oct. 4 in Cell Metabolism.

Imai says this discovery holds promise for people because the mechanisms that NMN influences are largely the same in mice and humans.

“But whether this mechanism is equally compromised in human patients with type 2 diabetes is something we have to check,” Imai says. “We have plans to do this in the very near future.”

All cells in the body make NMN in a chain of reactions leading to production of NAD, a vital molecule that harvests energy from nutrients and puts it into a form cells can use. Among other things, NAD activates a protein called SIRT1 that has been shown to promote healthy metabolism throughout the body, from the pancreas to the liver to muscle and fat tissue.

According to the study, aging and eating a high-fat diet reduce production of NMN, slowing the body’s production of NAD and leading to abnormal metabolic conditions such as diabetes. NAD cannot be given to the mice directly because of toxic effects. But after administering NMN, levels of NAD rise and the diabetic mice show dramatically improved responses to glucose. In some cases, they return to normal.

“I’m very excited to see these results because the effect of NMN is much bigger than other known compounds or chemicals,” says first author Jun Yoshino, MD, PhD, postdoctoral research associate. “Plus, the fact that the body naturally makes NMN is promising for translating these findings into humans.”

Imai and his colleagues found that young, healthy mice on a high-fat diet developed diabetes in six months or less. In these mice, they found that NAD levels were reduced. But after administering NMN, levels of NAD increased and the female mice had normal results in glucose tolerance tests — a measure of how well the body moves glucose from the blood to the organs and tissues for use. Glucose tolerance was also improved after male diabetic mice received NMN but did not quite return to normal. The researchers are interested in learning more about these differences between male and female mice.

“We don’t have a clear answer, but we are speculating that sex hormones, such as estrogen, may be important downstream for NAD synthesis,” Yoshino says.

In older mice, they observed that about 15 percent of healthy males fed a normal diet developed diabetes.

“When we injected these older diabetic mice with NMN, they had improved glucose tolerance, even after one injection,” says Kathryn F. Mills, research lab supervisor and an equally contributing first author of the study. “We also injected older healthy mice and found that they weren’t adversely affected. It’s good to know that even if the mice are not diabetic, giving NMN is not going to hurt them.”

Imai says few studies have examined normal mice that naturally develop diabetes as a simple result of aging because the experiments take so long. In an interesting twist, few elderly female mice developed diabetes at all. But after switching to a high fat diet, older female mice quickly developed severe diabetes.

“Again, when we injected these females with NMN, we came up with a completely normal glucose tolerance curve,” Mills says. “We can also see that the NMN has completely reversed and normalized the levels of cholesterol, triglycerides and free fatty acids.”

Though the mice received NMN by injection in this study, Imai’s group is now conducting a long-term study of diabetic mice that get NMN dissolved in their drinking water. Imai calls this work a first step toward a possible “nutriceutical” that people could take almost like a vitamin to treat or even prevent type 2 diabetes.

“Once we can get a grade of NMN that humans can take, we would really like to launch a pilot human study,” Imai says.

Green tea may slow down weight gain and serve as another tool in the fight against obesity, according to Penn State food scientists. (Credit: © Katarzyna Krawiec / Fotolia)

 

 

 

Penn State U, October 4, 2011  —  Green tea may slow down weight gain and serve as another tool in the fight against obesity, according to Penn State food scientists.

Obese mice that were fed a compound found in green tea along with a high-fat diet gained weight significantly more slowly than a control group of mice that did not receive the green tea supplement, said Joshua Lambert, assistant professor of food science in agricultural sciences.

“In this experiment, we see the rate of body weight gain slows down,” said Lambert.

The researchers, who released their findings in the current online version of Obesity, fed two groups of mice a high-fat diet. Mice that were fed Epigallocatechin-3-gallate — EGCG — a compound found in most green teas, along with a high-fat diet, gained weight 45 percent more slowly than the control group of mice eating the same diet without EGCG.

“Our results suggest that if you supplement with EGCG or green tea you gain weight more slowly,” said Lambert.

In addition to lower weight gain, the mice fed the green tea supplement showed a nearly 30 percent increase in fecal lipids, suggesting that the EGCG was limiting fat absorption, according to Lambert.

“There seems to be two prongs to this,” said Lambert. “First, EGCG reduces the ability to absorb fat and, second, it enhances the ability to use fat.”

The green tea did not appear to suppress appetite. Both groups of mice were fed the same amount of high-fat food and could eat at any time.

“There’s no difference in the amount of food the mice are eating,” said Lambert. “The mice are essentially eating a milkshake, except one group is eating a milkshake with green tea.”

A person would need to drink ten cups of green tea each day to match the amount of EGCG used in the study, according to Lambert. However, he said recent studies indicate that just drinking a few cups of green tea may help control weight.

“Human data — and there’s not a lot at this point — shows that tea drinkers who only consume one or more cups a day will see effects on body weight compared to nonconsumers,” said Lambert.

Lambert, who worked with Kimberly Grove and Sudathip Sae-tan, both graduate students in food science, and Mary Kennett, professor of veterinary and biomedical sciences, said that other experiments have shown that lean mice did not gain as much weight when green tea is added to a high fat diet. However, he said that studying mice that are already overweight is more relevant to humans because people often consider dietary changes only when they notice problems associated with obesity.

“Most people hit middle age and notice a paunch; then you decide to eat less, exercise and add green tea supplement,” said Lambert.

The National Institutes of Health supported this work.

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