On the role of T lymphocytes in stimulation of humoral immunity induced by peptidoglycan-monomer linked with zinc.
Effects of peptidoglycan linked with zinc (PGM-Zn) were investigated on plaque-forming cell (PFC) generation to sheep red blood cell (SRBC) and SRBC-unrelated antibody production in primary and secondary immune response in mice depleted in vivo of CD4+ and/or CD8+ T lymphocytes. PGM-Zn in nondepleted mice stimulated the PFC generation and IgM or IgG and IgG1 production in primary and secondary reaction. Single depletion of CD4 or CD8+ T cells did not change this ability. The effects of PGM-Zn after CD8+ depletion were even greater than those in nondepleted mice. Depletion of both T cell subsets, however, completely abrogated immunostimulatory effects of PGM on PFC generation (primary and secondary response), as well as on primary SRBC-unrelated antibody production, leaving only the increase of IgG in secondary response unchanged. Immunostimulatory effects and isotype switching to IgG1 and IgG2a correlated with the changes in splenic CD4+, CD8+, CD5+ cells, pointing to the regulatory role of these cells and/or their cytokines in PGM-Zn-induced immunostimulation. Altogether the data suggest that PGM-Zn may potentiate the costimulatory signals coming from activated T cells and act on B cells without the T cell help.
Ravlić-Gulan
J
J
Department of Physiology and Immunology, Medical Faculty, University of Rijeka, Croatia.
Radosević-Stasić
B
B
Trobonjaca
Z
Z
Petković
M
M
Cuk
M
M
Rukavina
D
D
D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000031:analogs & derivatives* / Q000276:immunology / Q000378:metabolism; D000818:Animals; D000917:Antibody Formation / Q000276:immunology*; D001854:Bone Marrow Cells / Q000166:cytology / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes; D018956:CD5 Antigens / Q000032:analysis; D018414:CD8-Positive T-Lymphocytes; D004912:Erythrocytes / Q000276:immunology; D006462:Hemolytic Plaque Technique; D008213:Lymphocyte Activation; D018655:Lymphocyte Count; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010457:Peptidoglycan; D012756:Sheep / Q000276:immunology; D013154:Spleen / Q000166:cytology / Q000276:immunology; D016176:T-Lymphocyte Subsets; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology; D015032:Zinc / Q000276:immunology* / Q000378:metabolism
D018956:CD5 Antigens; D010457:Peptidoglycan; D000119:Acetylmuramyl-Alanyl-Isoglutamine; C032972:peptidoglycan pentapeptide-mDap3; D015032:Zinc