ABSTRACT
Perforin-mediated cytotoxic T cell killing has been suggested to be of importance in the control of noncytopathic virus infections, based on studies with lymphocytic choriomeningitis virus (LCMV). We examined the role of perforin in a mouse model of gammaherpesvirus infection using transgenic perforin-deficient mice. Previous work from this laboratory has shown that CD8 T cells are essential for the resolution of the acute lung infection and control of latently infected B cells in murine gamma-herpesvirus 68 infection. The absence of perforin did not significantly affect the kinetics of either the lytic lung infection or the latent spleen infection. Lymphocytes from both perforin-deficient and control mice secreted comparable levels of IFN-gamma, IL-10 and IL-6. In addition, lymphocytes from both strains had similar levels of CD3epsilon-dependent cytotoxic activity in the spleen, draining lymph nodes and bronchoalveolar lavage. These data indicate that the lack of perforin has little affect on the ability of mice to control an experimental gammaherpesvirus infection.
Subject(s)
CD8-Positive T-Lymphocytes/immunology , Cytokines/biosynthesis , Gammaherpesvirinae , Herpesviridae Infections/immunology , Membrane Glycoproteins/physiology , T-Lymphocytes, Cytotoxic/immunology , Animals , Cell Line , Cricetinae , Gammaherpesvirinae/immunology , Gammaherpesvirinae/pathogenicity , Interferon-gamma/biosynthesis , Interleukin-10/biosynthesis , Interleukin-6/biosynthesis , Lung/immunology , Lung/virology , Lymph Nodes/immunology , Membrane Glycoproteins/deficiency , Mice , Mice, Inbred C57BL , Mice, Transgenic , Perforin , Pore Forming Cytotoxic Proteins , Spleen/immunology , Spleen/virologyABSTRACT
The development of a reagent-impregnated paper strip test for niacin is described. The test system is based on the formation of cyanogen chloride by the reaction of chloramine-T and potassium thiocyanate in the presence of citric acid. Rupture of the pyridine ring of niacin by cyanogen chloride yields gamma-carboxy glutaconic aldehyde and coupling with a primary aromatic amine produces a yellow color. Sensitivity to niacin, both in known solutions and from extracts of 378 clinical mycobacteria isolates, equalled or exceeded that of other methods for detection of niacin. Correlation with other tests for mycobacterial niacin was excellent.
