Thyrotropin: an endogenous regulator of the in vitro immune response.
We have previously shown that thyrotropin (TSH), which is produced by lymphocytes in response to the T cell mitogen staphylococcal enterotoxin A, enhances in vitro antibody production to T cell-dependent and independent Ag (SRBC and trinitrophenylated Brucella abortus [BA-TPN], respectively) as determined by a direct plaque-forming cell assay. As a result of these studies, experiments were designed to examine the possible immunoregulatory function of thyrotropin-releasing hormone (TRH) on the in vitro antibody response to the T cell-independent Ag BA-TNP. Our studies demonstrate that TRH at very low concentrations (pM) enhances the in vitro plaque-forming cell response to BA-TNP and also induces splenocyte production of TSH. Other hypothalamic-releasing factors were without effect. This enhancement effect by TRH was specifically blocked by rabbit antisera to the TSH-beta subunit, whereas addition of normal rabbit sera had no effect. These data suggest that TRH specifically enhances the in vitro antibody response via production of immunoreactive TSH.
Kruger
T E
TE
Department of Physiology and Biophysics, University of Alabama, Birmingham 35294.
Smith
L R
LR
Harbour
D V
DV
Blalock
J E
JE
D000276:Adjuvants, Immunologic / Q000502:physiology*; D000818:Animals; D000917:Antibody Formation / Q000187:drug effects*; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D002003:Brucella abortus / Q000276:immunology; D006462:Hemolytic Plaque Technique; D007106:Immune Sera / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D009693:Nucleic Acid Hybridization; D012333:RNA, Messenger / Q000302:isolation & purification; D013154:Spleen; D013972:Thyrotropin / Q000096:biosynthesis / Q000276:immunology / Q000502:physiology*; D013973:Thyrotropin-Releasing Hormone / Q000502:physiology; D014301:Trinitrobenzenes / Q000276:immunology
D000276:Adjuvants, Immunologic; D007106:Immune Sera; D012333:RNA, Messenger; D014301:Trinitrobenzenes; D013973:Thyrotropin-Releasing Hormone; D013972:Thyrotropin