title: Phenotypic and functional analysis of mucosal lymph node T cell subpopulations proximal and distal to chronic staphylococcal antigen challenge.
abstract: We investigated the functional and subset surface marker characteristics of supramammary lymph node T cell populations at sites proximal and distal to the mammary region of goats repeatedly injected with heat-treated Staphylococcus aureus antigen (HK-SAC). Flow cytometric studies showed quantitative differences in CD4+ and CD8+ T cell subsets among large and small lymphocyte populations in ipsilateral and contralateral supramammary lymph nodes of these animals. Although ipsilateral (draining) lymph nodes were enriched with CD4+ and CD8+ T cells, CD4/CD8 ratios were comparatively lower than those of contralateral (non-draining) lymph nodes (2.30 vs 2.60, respectively). Cell size analysis by flow cytometry showed that nearly 70% of the lymphocytes in ipsilateral nodes were of large cell phenotype with CD4/CD8 ratios of 2.52. In contrast, there were only 56.1% large lymphocytes in contralateral lymph nodes but with similar CD4/CD8 ratios of 2.55. The number of large lymphocytes in corresponding nodes of uninoculated control animals was significantly lower (50%) with much lower CD4/CD8 ratios (2.08). Alloantigenic responses of both ipsilateral and contralateral lymph node T cells were greater than those of uninoculated controls. Antigen-specific proliferation studies showed that ipsilateral lymph node T cells greatly enhanced both primed and non-primed lymph node B cell responses to HK-SAC, whereas those from contralateral lymph nodes were less stimulatory. In contrast, contralateral lymph node T cells had greater enhancing effects on PWM-induced polyclonal B cell responses. These studies indicate that repeated local infection with bacterial antigen induce changes in the numbers, ratios and antigen-specific and non-specific responses among ipsilateral (draining) and distal contralateral (non-draining) lymph node T cell populations in mucosal-associated immune systems such as the mammary gland.
authors.affiliation: Department of Pathobiology, University of Connecticut, Storrs 06269-3089.
authors.forename: M J
authors.initials: MJ
authors.lastname: Dobrzanski
authors.forename: T J
authors.initials: TJ
authors.lastname: Yang
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000008:administration & dosage*; D016516:CD4-CD8 Ratio; D005260:Female; D006041:Goats; D007114:Immunization; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D008321:Mammary Glands, Animal / Q000276:immunology; D009092:Mucous Membrane / Q000276:immunology; D013211:Staphylococcus aureus / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial