SAFETY AND IMMUNOGENICITY OF STAPHYLOCOCCUS-AUREUS TYPE 5 CAPSULAR POLYSACCHARIDE-PSEUDOMONAS-AERUGINOSA RECOMBINANT EXOPROTEIN-A CONJUGATEVACCINE IN PATIENTS ON HEMODIALYSIS

Seventeen volunteers with ESRD on hemodialysis, negative for infection with HIV or hepatitis B and C and not receiving immunosuppressive the rapy, were injected two times 6 wk apart with 25 mu g of Staphylococcu s aureus Type 5 capsular polysaccharide-Pseudomonos aeruginosa exoprot ein A (rEPA) conjugate, Controls were healthy adults, 18 to 44 yr old, injected previously with the same vaccine. None of the patients had f ever or significant elevations in their SGOT or SGPT attributable to t he vaccine, Two vaccinees had transient induration >1 cm in diameter a t the injection site, The preimmunization geometric mean (GM) Type 5 a ntibody levels of the ESRD patients and controls were similar, Type 5 antibody levels of the three major immunoglobulin (Ig) classes rose at 2 and 6 wk after immunization (P < 0.001 for IgG, P < 0.005 for IgM, and P = 0.0001 for IgA), Reimmunization at 6 wk did not elicit a boost er response, At 6 months, the GM IgG level of the patients was approxi mately 50% of that of the healthy volunteers and 14 of 17 had a more t han fourfold higher antibody level than the preimmune value, The GM Ig M level, in contrast, declined to the preimmunization value. Vaccine-i nduced Type 5 antibodies had opsonophagocytic activity, There was a sl ight increase of IgG antibodies to the heterologous S. aureus Type 8 p olysaccharide (P < 0.01) that was sustained at 6 months. The S. aureus Type 5-rEPA vaccine is safe and immunogenic in ESRD patients, and eva luation of its effectiveness against S. aureus bacteremia in this at-r isk group is planned.