ALTERATION OF INTERLEUKIN-1-ALPHA PRODUCTION AND INTERLEUKIN-1-ALPHA BINDING-SITES IN MOUSE-BRAIN DURING RABIES INFECTION

We have evaluated the effect of rabies virus infection on interleukin- 1 alpha (IL-1 alpha) production and its receptors in mouse brain. Stud y of virus dissemination in the central nervous system (CNS) showed a massive infection of main brain structures from day 4 post infection ( p.i.) up to the agony stage on day 6 p.i. At the same time, IL-1 alpha concentrations increased in cortical and hippocampal homogenates, whe reas no change was detected in serum. In non-infected mice, IL-1 alpha binding sites were observed in the dentate gyrus, the cortex, the cho roid plexus, the meninges and the anterior pituitary. During rabies vi rus infection, a striking decrease in IL-1 alpha binding sites was obs erved on day 4 p.i. with a complete disappearance on day 6 p.i., excep t in the pituitary gland where they remained at control level. In conc lusion, concomitantly with the early rabid pathological signs, brain I L-1 alpha production and IL-1 alpha binding sites are specifically and significantly altered by brain viral proliferation. These results ind icate that IL-1 alpha could be involved in the brain response to viral infection as a mediator and could participate in the genesis of the r abies pathogeny.