SYSTEMIC IMMUNIZATION WITH HSP60 ALTERS THE DEVELOPMENT OF CHLAMYDIALOCULAR DISEASE

Purpose. To determine whether immunization with recombinant Hsp60 woul d exacerbate ocular pathology on challenge with viable chlamydial elem entary bodies. Methods. Guinea pigs were immunized either subcutaneous ly with recombinant Hsp60 or both subcutaneously with recombinant Hsp6 0 and ocularly with attenuated Salmonella lyphimurium expressing the g uinea pig inclusion conjunctivitis (GPIC) Hsp60 antigen. All animals w ere challenged in the conjunctiva with the agent of GPIC, and the degr ee of gross ocular pathology was determined. Immunoglobulin G (IgG) an d immunoglobulin A (IgA) antibody titers to Hsp60 were measured in ocu lar secretions as a measure of the degree of immunization. Results, In primary and challenge GPIC infection, the degree of gross ocular path ology was lower in the immunized group. The presence of high IgA and I gG antibody titers to Hsp60 in tears suggested that the response may h ave been modified by the presence of blocking antibodies that either m ay have removed the antigen quickly or prevented interaction with sens itized T cells. In contrast to subcutaneous immunization, the combined immunization regimen, consisting of subcutaneous recombinant Hsp60 fo llowed by ocular inoculation of the attenuated Salmonella, resulted in no difference in gross pathology after reinfection of guinea pigs wit h GPIC. Conclusions. These data indicated that the immunization with H sp60 did not produce exacerbated disease on challenge with viable orga nisms; however, the data suggested that the route of administration, f orm of antigen, or both may be critical in the disease process.