Effect of pregnancy serum on experimental inflammation.

Abstract Experimental inflammation induced in the rat by injection of carrageenin was suppressed by prior administration of pooled serum obtained from pregnant human females. Inflammatory oedema in the rat hind paw measured by a plethysmograph was inhibited 81% by 10 ml of pregnancy serum pool and the effect was dose related. Non-pregnant female serum was inhibitory to a lesser degree and no anti-inflammatory action was detected using cord serum. Although adrenal corticosteroid hormones could modify this inflammatory model, their presence in the serum pools could not account for the effects observed. Since carrageenin is sequestered within phagolysosomes and provokes release of their inflammation-inducing contents, it is suggested that the protective effect of pregnancy serum on carrageenin inflammation is mediated via lysosomal stabilization.