Effect of tear secretory IgA on chemotaxis of polymorphonuclear leucocytes

Abstract

Purpose: The aim of the present study was to examine the effect of tear and purified colostrum secretory IgA (sIgA) on polymorphonuclear leucocyte (PMN) chemotaxis. Methods: The chemotactic effect of tear and purified sIgA for PMN was studied using a modified Boyden chamber. Tears treated with anti- human IgA, complement-inactivated tears and albumin were used as controls. Results: The data indicate that both tear and purified sIgA are highly chemotactic for PMN. Anti-sIgA antibodies reduced the chemotactic effect of closed-eye tears (34%) and tear collected during ocular inflammation. Conclusion: The massive recruitment of PMN in tears during sleep may be partially attributed to the increased levels of tear sIgA. This may play an important role in protecting the eye against bacterial infection.