Granulocyte factor and graft-versus-host reaction in rats. I. The inhibitory effect of granulocyte factor on the local graft-versus-host reaction in rats.

Recent data have proved that PMNLs regulate the immune responses in vitro and in vivo. PMNL specific granules contain an immunoregulatory factor termed the granulocyte factor (GF). The glycogen-induced PMNL infiltration to peritoneal cavity of rats significantly diminished the local GvHR. GF, injected subcutaneously three times at a day of challenge, one and two days after, significantly diminished local GvHR as well. GF treatment before parental lymphocyte injection had no effect on the local GvHR in rats. Inactivation of GF using anti-GF IgG antibodies, abolished the inhibitory effect of PMNLs in GvHR.