IN-VITRO SUPERFUSION METHOD FOR THE INVESTIGATION OF NERVE-IMMUNE CELL-INTERACTION IN MURINE SPLEEN

Immune defence mechanisms can be modulated by brain function. To study such interactions, an in vitro method was developed to examine the re lease of cytokines and norepinephrine (NE) after electrical stimulatio n. Slices of mouse spleen were placed in chambers with a volume of 80 mu l and superfused with culture medium. To characterize electrically evoked NE release and cell viability a suitable stimulation protocol w as developed using of [H-3]NE. As parameter for immune function, modul ation of interleukin-6 (IL-6) release by the spleen cells brought abou t by electrical stimulation was investigated. Splenic [H-3]NE overflow was calcium-dependent, tetrodotoxin-sensitive and elicited by 54 mM p otassium. Electrically evoked [H-3]NE release at 22 h was about 80% of the release at 5.3 h. Electrical stimulation substantially reduced IL -6 secretion at 6 h (control: 143.4 +/- 14.3 vs, electrical: 71.3 +/- 7.9 pg/ml/10(6) leukocytes, P = 0.0001). This effect was inhibited in a concentration-dependent manner by the beta-adrenergic antagonist pro pranolol (P = 0.0298, EC(50) approx. 10(-7) M). In conclusion, this ne w technique allows long-term. investigation of cell function in slices of murine spleen. In addition, these are the first in vitro data indi cating the presence of a functional neuroimmunological link in murine lymphoid tissue.