Enter Your Search:
Results 1-3 (3)
Go to page number:
Select a Filter Below
Clinical and Diagnostic Laboratory Immunology (1)
Clinical and Vaccine Immunology (1)
Hines, Stephen A. (2)
Lopez, A. Marianela (2)
Alperin, Debra C. (1)
Berry, Jody (1)
Cunha, Cristina W. (1)
Dellagostin, Odir A. (1)
Hines, Melissa T. (1)
Joyee, Antony George (1)
Kappmeyer, Lowell S. (1)
Knowles, Donald P. (1)
Lin, Francis (1)
Lopez, Marianela (1)
Ma, Xiuli (1)
McGuire, Travis C. (1)
Nandagopal, Saravanan (1)
Palmer, Guy H. (1)
Wu, Dan (1)
Year of Publication
Did you mean:
author:("Lopez, A. mariana")
Effects of Clostridium difficile Toxin A and B on Human T Lymphocyte Migration
Joyee, Antony George
Bacterial products such as toxins can interfere with a variety of cellular processes, leading to severe human diseases. Clostridium difficile toxins, TcdA and TcdB are the primary contributing factors to the pathogenesis of C. difficile-associated diseases (CDAD). While the mechanisms for TcdA and TcdB mediated cellular responses are complex, it has been shown that these toxins can alter chemotactic responses of neutrophils and intestinal epithelial cells leading to innate immune responses and tissue damages. The effects of C. difficile toxins on the migration and trafficking of other leukocyte subsets, such as T lymphocytes, are not clear and may have potential implications for adaptive immunity. We investigated here the direct and indirect effects of TcdA and TcdB on the migration of human blood T cells using conventional cell migration assays and microfluidic devices. It has been found that, although both toxins decrease T cell motility, only TcdA but not TcdB decreases T cell chemotaxis. Similar effects are observed in T cell migration toward the TcdA- or TcdB-treated human epithelial cells. Our study demonstrated the primary role of TcdA (compared to TcdB) in altering T cell migration and chemotaxis, suggesting possible implications for C. difficile toxin mediated adaptive immune responses in CDAD.
C. difficile toxin A and B; human T lymphocyte; cell migration; chemotaxis; microfluidic device
Development of Specific Immunoglobulin Ga (IgGa) and IgGb Antibodies Correlates with Control of Parasitemia in Babesia equi Infection
Cunha, Cristina W.
McGuire, Travis C.
Kappmeyer, Lowell S.
Hines, Stephen A.
Dellagostin, Odir A.
Knowles, Donald P.
Clinical and Vaccine Immunology
In this study, the kinetics of specific immunoglobulin G (IgG) isotypes were characterized in Babesia equi (Theileria equi)-infected horses. IgGa and IgGb developed during acute infection, whereas IgG(T) was detected only after resolution of acute parasitemia. The same IgG isotype profile induced during acute infection was obtained by equi merozoite antigen 1/saponin immunization.
Identification of Pulmonary T-Lymphocyte and Serum Antibody Isotype Responses Associated with Protection against Rhodococcus equi
Hines, Melissa T.
Palmer, Guy H.
Alperin, Debra C.
Hines, Stephen A.
Clinical and Diagnostic Laboratory Immunology
Rhodococcus equi infects and causes pneumonia in foals between 2 and 4 months of age but does not induce disease in immunocompetent adults, which are immune and remain clinically normal upon challenge. Understanding the protective response against R. equi in adult horses is important in the development of vaccine strategies, since those mechanisms likely reflect the protective phenotype that an effective vaccine would generate in the foal. Twelve adult horses were challenged with virulent R. equi and shown to be protected against clinical disease. Stimulation of cells obtained from bronchoalveolar lavage fluid with either R. equi or the vaccine candidate protein VapA resulted in significant proliferation and a significant increase in the level of gamma interferon (IFN-γ) expression by day 7 postchallenge. The levels of interleukin-4 expression were also increased at day 7 postchallenge; however, this increase was not antigen specific. Anamnestic increases in the levels of binding to R. equi and VapA of all immunoglobulin G (IgG) antibody isotypes [IgGa, IgGb, IgG(T)] examined were detected postchallenge. The levels of R. equi- and VapA-specific IgGa and IgGb antibodies, the IgG isotypes that preferentially opsonize and fix complement in horses, were dramatically enhanced postchallenge. The antigen-specific proliferation of bronchoalveolar lavage fluid cells, the levels of IFN-γ expression by these cells, and the anamnestic increases in the levels of opsonizing IgG isotypes are consistent with stimulation of a memory response in immune adult horses and represent correlates for vaccine development in foals.
Results 1-3 (3)
Go to page number:
Remove citation from clipboard
Add citation to clipboard
This will clear all selections from your clipboard. Do you wish proceed?
Clipboard is full! Please remove an item and try again.
PubMed Central Canada is a service of the
Canadian Institutes of Health Research
(CIHR) working in partnership with the National Research Council's
Canada Institute for Scientific and Technical Information
in cooperation with the
National Center for Biotechnology Information
U.S. National Library of Medicine
(NCBI/NLM). It includes content provided to the
PubMed Central International archive
by participating publishers.