151 M O N O C L O N A L ANTIBODIES SPECIFIC TO THE PHYLOGENETICALLY STABLE NEURONAL STRUCTURES O F T H E RAT BRAIN Veretennikov N.A., Leontovich T.A. Brain Research Institute of the Academy of Medical Sciences of the USSR, Moscow, USSR We have raised monoclonal antibodies (MAbs) against the proteins extract of the fixed gray matter of the brain stem of the cat (McKay, Hockfield, 1982) with the aim of finding ligands that recognize particular cytological nem'al s*.ructuresThe splenocytes were fused with Xb3-Ag8-653 myeloma cells by using 50% PEG 1500, following the standard procedure. For light microscopic immunohistochemistry, supematants of the hybridoma microcultures were screened by indirect immunoperoxidase technique of c~ostat 18 mkm thick horizontal sections of fresh rat brain. The MAbs to neural cat's antigens 1A4 and 3El 1 (two of the several MAbs obtained) stain the specific antigens of the rat brain. 1A4 recognizes only the large motoneurons of nucleus hypoglnssus and Purkinje cells (premotor). 1A~-stains only *,hemembrane structures of the cytoplasm of the cell bodies without staining the surface membranes, nuclei and processes of the mentioned types of neurons. 3El 1 stains presinaptic boutons (densely and uniformly stained mass of small dots) on the surface nf dendrites but not cell bodies in phylogeneticallyold cortical regions: in cerebellar cortex (g:anular layer) and all layers of Ammon's horn. The restricted distribotion of tbe antigen IA4 [i.e. molecule(s) recognized by 1A4] within motor and premotor neurolts suggests that the antigen molecule is most likely involved in ftmctions specific to the large effector neurons and the distribution of 3El 1 may point to existing of molecules specific to other structures and functions remaining undetermined.
BLOCKING O F IL=I INDUCED INFLAMMATION BY MONOCLONAL ANTIBODIES TO ADHESION MOLECULES J a m e s A. M a r t i n e y , T i n a M. Calderon, J o a n W . B e r m a n , and Celia F. Brosnan, Department of Pathology, Albert Einstein College of Medicine, Bronx, N Y , USA. PreviowJ results from this laboratory have shown that intraocular injection of intedeukin-l[~ (IL-1 [~) in the rabbit retina induces an acute and chronic inflammatory response associated with the epiretinal vessels. Analysis of this reaction have defined the following series cf event~ associated with the acute inflammatory episode: a mononuelear (MN) and polymorphonuclear (PMN) exudate accompanied by an increase in vascular permeability and hemorrhage that peaks between 6 arid 24 hours post-intraocular challenge (PIC). No fvxther migration of PMN or hemorrhagic events occurred after 24h PIC. A more persistent MN cellular inflammation followed this acute episode. To test the role of specific adhesion molecules in these events, monoclonal antibodies (MAbs) directed against CD18, the ~oitmlun beta chain of the intcgrin LFA-I. (RI5.7, provided by R. Rothlein) and agair~*,a novel endothelial cell adhesion mol~u!e specific for monocytes (iG9, Calderon et al., Circulation V82, p. III-94, 1990) were employed. The results show that significant inhibi:ion of all parameters of inflammation was achieved with beth MAbs, including a rc~luction of the IL l-induced increase in vascular permeability and hemorrhage. However, the pattern of reduction of cellular inflammation was different between the two MAbs. With the MAb RI5.7, the most striking change was a decrease in PMN and MN extravasation whereas wi',h MAb IG9 both intravascular and extravascular PIVlNand MN cell numbers were decreased. Interestingly, eontr~lateral eye involvement due to systemic effects was also inhibited in these animals. Supported by NS11920 and 07089.