Temperature-mediated processes in teleost immunity: homeoviscous adaptation by channel catfish peripheral blood cells.
1. Channel catfish peripheral blood erythrocyte, thrombocyte, T cell and B cell membranes were assayed by fluorescence depolarization using the fluorescent probe 1,6-diphenyl-1,3,5 hexatriene (DPH) to determine the effects of in vivo temperature acclimation on membrane viscosity and the kinetics of homeoviscous adaptation. 2. Erythrocyte membranes did not undergo homeoviscous adaptation during the 8 week time period studied and were more rigid compared with those of the other cell types. 3. The kinetics of homeoviscous adaptation exhibited by membranes from T cells, B cells and thrombocytes differed: B cells required 1-3 weeks while T cells and thrombocytes each required 3-5 weeks. Membranes from T cells, B cells and thrombocytes from fish acclimated for relatively short times (less than or equal to 3 weeks) exhibited similar membrane fluidities. 4. T cells from channel catfish appeared not only to be sensitive to temperature but also to a factor(s) independent of temperature but correlated to long term in vivo acclimation, i.e. T cell membranes underwent additional decreases in membrane viscosity between 3 and 5 weeks. 5. In conclusion, it appears that low temperature-mediated immunosuppression of T cell functions in channel catfish is probably not due to an inherent non-adaptability or rigid nature of the T cell membranes.
Bly
J E
JE
Department of Microbiology, University of Mississippi Medical Center, Jackson 39216-4504.
Clem
L W
LW
D000222:Adaptation, Physiological; D000818:Animals; D001792:Blood Platelets / Q000502:physiology; D002397:Catfishes / Q000276:immunology*; D002462:Cell Membrane / Q000502:physiology; D004912:Erythrocytes / Q000502:physiology; D007059:Ictaluridae / Q000276:immunology*; D008214:Lymphocytes / Q000502:physiology; D013696:Temperature