Carol Pontzer - Academia.edu (original) (raw)

Papers by Carol Pontzer

Research paper thumbnail of Identification of a Transcytosis Epitope on Staphylococcal Enterotoxins

Infection and Immunity, 2002

Staphylococcal enterotoxins (SE) are exoproteins produced by Staphylococcus aureus that act as su... more Staphylococcal enterotoxins (SE) are exoproteins produced by Staphylococcus aureus that act as superantigens and have been implicated as a leading cause of food-borne disease and toxic shock. Little is known about how these molecules penetrate the gut lining and gain access to both local and systemic immune tissues. To model movement in vitro of staphylococcal enterotoxins, we have employed a monolayer system composed of crypt-like human colonic T-84 cells. SEB and SEA showed comparable dose-dependent transcytosis in vitro, while toxic shock syndrome toxin (TSST-1) exhibited increased movement at lower doses. Synthetic peptides corresponding to specific regions of the SEB molecule were tested in vitro to identify the domain of the protein involved in the transcytosis of SE. A toxin peptide of particular interest contains the amino acid sequence KKKVTAQELD, which is highly conserved across all SE. At a toxin-to-peptide ratio of 1:10, movement of SEB across the monolayers was reduced by 85%. Antisera made against the SEB peptide recognized native SEB and also inhibited SEB transcytosis. Finally, the conserved 10-amino-acid peptide inhibited transcytosis of multiple staphylococcal enterotoxins, SEA, SEE, and TSST-1. These data demonstrate that this region of the staphylococcal enterotoxins plays a distinct role in toxin movement across epithelial cells. It has implications for the prevention of staphylococcal enterotoxin-mediated disease by design of a peptide vaccine that could reduce systemic exposure to oral or inhaled superantigens. Since the sequence identified is highly conserved, it allows for a single epitope blocking the transcytosis of multiple SE.

Research paper thumbnail of Lactobacilli and Bifidobacteria

Encyclopedia of Dietary Supplements, Second Edition, 2010

Research paper thumbnail of Guidance from an NIH Workshop on Designing, Implementing, and Reporting Clinical Studies of Soy Interventions

Journal of Nutrition, 2010

The NIH sponsored a scientific workshop, "Soy Protein/Isoflavone Research: Challenges in Designin... more The NIH sponsored a scientific workshop, "Soy Protein/Isoflavone Research: Challenges in Designing and Evaluating Intervention Studies," July 28-29, 2009. The workshop goal was to provide guidance for the next generation of soy protein/isoflavone human research. Session topics included population exposure to soy; the variability of the human response to soy; product composition; methods, tools, and resources available to estimate exposure and protocol adherence; and analytical methods to assess soy in foods and supplements and analytes in biologic fluids and other tissues. The intent of the workshop was to address the quality of soy studies, not the efficacy or safety of soy. Prior NIH workshops and an evidence-based review questioned the quality of data from human soy studies. If clinical studies are pursued, investigators need to ensure that the experimental designs are optimal and the studies properly executed. The workshop participants identified methodological issues that may confound study results and interpretation. Scientifically sound and useful options for dealing with these issues were discussed. The resulting guidance is presented in this document with a brief rationale. The guidance is specific to soy clinical research and does not address nonsoy-related factors that should also be considered in designing and reporting clinical studies. This guidance may be used by investigators, journal editors, study sponsors, and protocol reviewers for a variety of purposes, including designing and implementing trials, reporting results, and interpreting published epidemiological and clinical studies.

Research paper thumbnail of Racing Toward The Integration Of Complementary And Alternative Medicine: A Marathon Or A Sprint?

Health Affairs, 2005

Health care opinion leaders concur that integration of complementary and alternative medicine (CA... more Health care opinion leaders concur that integration of complementary and alternative medicine (CAM) into the U.S. health care system must be based on strong supporting evidence of safety and efficacy. As others have pointed out, integration is under way, despite the lack of reliable, rigorous science supporting the use of most CAM treatments. We contend that optimal integration of CAM is a long-term endeavor--a marathon rather than a sprint. The evidence base does not now support its wholesale assimilation; market forces, although compelling, should not be the primary consideration in integration.

Research paper thumbnail of The NIH Human Microbiome Project

Research paper thumbnail of National Institutes of Health Gastrointestinal Microbiota and Advances in Prebiotic and Probiotic Research Conference Summary

Research paper thumbnail of Identification of a Transcytosis Epitope on Staphylococcal Enterotoxins

Infection and Immunity, 2002

Staphylococcal enterotoxins (SE) are exoproteins produced by Staphylococcus aureus that act as su... more Staphylococcal enterotoxins (SE) are exoproteins produced by Staphylococcus aureus that act as superantigens and have been implicated as a leading cause of food-borne disease and toxic shock. Little is known about how these molecules penetrate the gut lining and gain access to both local and systemic immune tissues. To model movement in vitro of staphylococcal enterotoxins, we have employed a monolayer system composed of crypt-like human colonic T-84 cells. SEB and SEA showed comparable dose-dependent transcytosis in vitro, while toxic shock syndrome toxin (TSST-1) exhibited increased movement at lower doses. Synthetic peptides corresponding to specific regions of the SEB molecule were tested in vitro to identify the domain of the protein involved in the transcytosis of SE. A toxin peptide of particular interest contains the amino acid sequence KKKVTAQELD, which is highly conserved across all SE. At a toxin-to-peptide ratio of 1:10, movement of SEB across the monolayers was reduced by 85%. Antisera made against the SEB peptide recognized native SEB and also inhibited SEB transcytosis. Finally, the conserved 10-amino-acid peptide inhibited transcytosis of multiple staphylococcal enterotoxins, SEA, SEE, and TSST-1. These data demonstrate that this region of the staphylococcal enterotoxins plays a distinct role in toxin movement across epithelial cells. It has implications for the prevention of staphylococcal enterotoxin-mediated disease by design of a peptide vaccine that could reduce systemic exposure to oral or inhaled superantigens. Since the sequence identified is highly conserved, it allows for a single epitope blocking the transcytosis of multiple SE.

Research paper thumbnail of Lactobacilli and Bifidobacteria

Encyclopedia of Dietary Supplements, Second Edition, 2010

Research paper thumbnail of Guidance from an NIH Workshop on Designing, Implementing, and Reporting Clinical Studies of Soy Interventions

Journal of Nutrition, 2010

The NIH sponsored a scientific workshop, "Soy Protein/Isoflavone Research: Challenges in Designin... more The NIH sponsored a scientific workshop, "Soy Protein/Isoflavone Research: Challenges in Designing and Evaluating Intervention Studies," July 28-29, 2009. The workshop goal was to provide guidance for the next generation of soy protein/isoflavone human research. Session topics included population exposure to soy; the variability of the human response to soy; product composition; methods, tools, and resources available to estimate exposure and protocol adherence; and analytical methods to assess soy in foods and supplements and analytes in biologic fluids and other tissues. The intent of the workshop was to address the quality of soy studies, not the efficacy or safety of soy. Prior NIH workshops and an evidence-based review questioned the quality of data from human soy studies. If clinical studies are pursued, investigators need to ensure that the experimental designs are optimal and the studies properly executed. The workshop participants identified methodological issues that may confound study results and interpretation. Scientifically sound and useful options for dealing with these issues were discussed. The resulting guidance is presented in this document with a brief rationale. The guidance is specific to soy clinical research and does not address nonsoy-related factors that should also be considered in designing and reporting clinical studies. This guidance may be used by investigators, journal editors, study sponsors, and protocol reviewers for a variety of purposes, including designing and implementing trials, reporting results, and interpreting published epidemiological and clinical studies.

Research paper thumbnail of Racing Toward The Integration Of Complementary And Alternative Medicine: A Marathon Or A Sprint?

Health Affairs, 2005

Health care opinion leaders concur that integration of complementary and alternative medicine (CA... more Health care opinion leaders concur that integration of complementary and alternative medicine (CAM) into the U.S. health care system must be based on strong supporting evidence of safety and efficacy. As others have pointed out, integration is under way, despite the lack of reliable, rigorous science supporting the use of most CAM treatments. We contend that optimal integration of CAM is a long-term endeavor--a marathon rather than a sprint. The evidence base does not now support its wholesale assimilation; market forces, although compelling, should not be the primary consideration in integration.

Research paper thumbnail of The NIH Human Microbiome Project

Research paper thumbnail of National Institutes of Health Gastrointestinal Microbiota and Advances in Prebiotic and Probiotic Research Conference Summary