Neuroendocrine regulation of immune parameters: Photoperiod control of the spleen in Syrian hamsters

21 ENCEPHALITOGENIC ACTIVITY OF SJL/J T CELL LINES SPECIFIC FOR BASIC PROTEIN AND THE 1-37 AND 89-169 FRAGMENTS OF GUINEA PIG BASIC PROTEIN Dennis N. Bourdette, Arthur A. Vandenbark, Ruth H. Whitham, Charles K. Meshul, C.H. Jen Chou, and Halina Offner, VA Medical Center and Oregon Health Sciences University, Portland, OR and Emory University, Atlanta, GA We developed myelin basic protein (BP) specific T cell lines from SJL/J mice following techniques used to develop similar lines from Lewis rats (Vandenbark, et al, J Immunol 1985;135:223). These lines proliferated specifically to BP and induced chronic relapsing experimental autoimmune encephalomyelitis ~EAE) in naive animals. Thirty-two of 41 animals that received 3-20 X 10 T cells developed acute EAE and 17 of 23 animals that survived longer than 30 days had one or more relapses. Pathologic examination revealed plaques of demyelination associated with inflammatory cells. Lewis rat BP specific T cell lines respond only to fragments containing the Lewis rat encephalitogenic determinant (Vandenbark, et al, J Immunol 1985;135:229). The SJL/J BP specific T cell lines responded not only to the 89-169 fragment, which contains the major encephslltogenic determinant for SJL/J mice, but also to the 1-37 fragment, although they did not respond to the 43-88 fragment. BP specific T cell lines stimulated with either the 1-37 or the 89-169 fragments induced FAE, suggesting that the 1-37 fragment might contain a second SJL/J encephalitogenic determinant. We selected T cell lines specific for either the 1-37 or the 89-169 fragment using HPLC purified fragments. The encephalitogenic activity of these fragment specific T cells is currently under investigation. Supported in part by the Veterans Administration.

N E U R O E N D O C R I N E REGULATION OF IMMUNE PARAMETERS: CONTROL OF THE SPLEEN IN SYRIAN HAMSTERS

PHOTOPERIOD

George Brainard, Marcia Watson-Whitmeyer, Robert Knobler, and Fred Lublin, Department of Neurology, J e f f e r s o n Medical College, Philadelphia, PA 19107 and Department of Biology, School of Life and Health Sciences, U n i v e r s i t y of Delaware, Newark, DE 19716

Seasonally breeding mammals may be ideal animal models for studying interactions between the immune and nervous systems. The Syrian hamster (Mesocricetus auratus) is a seasonally b r e e d i n g mammal which has been extensively used to demonstrate the n e u r o e n d o c r i n e - r e P r o d u c t i v e effects of long and short photoperiods. Syrian hamsters are reproductively competent when exposed to long photoperiods. In contrast, exposure of these animals to short daylengths (less than 12.5 hours of light) induces a d e p r e s s i o n of the reproductive system. In addition to s u p p r e s s i n g reproduction, short photoperiods induce changes in selected immunological measures. Specifically, splenic weight, lymphocyte counts and macrophage counts were higher in animals housed in short daylengths. However, thymic weight and antibody