Antibody responses following splenectomy: implications for the timing of prophylactic vaccination

Antibody responses are reduced both in the short- and long-term after splenectomy. It is not known if this reduction is more profound in the immediate postoperative period compared to later, and consequently, whether there would be an advantage in delaying prophylactic vaccination to ensure a greater antibody response. To investigate this, the effect of splenectomy on the primary and secondary antibody response to sheep red blood cells (SRBC) injected into the peritoneum (IP) of adult male Porton rats was measured after either splenectomy (Spx), sham splenectomy (Sham), anaesthesia only (Ans) or no procedure at all (Con). There was no difference in the titres of antibody between the Con and the Ans rats. There was no difference in the titres of antibody between the Sham and Spx rats, but both had significantly lower titres than the Con rats. In a separate experiment, rats were immunized 1 month or 1 year after splenectomy or sham-splenectomy. One month after the operation the antibody response of the Sham rats had increased and did not differ from that of Con rats, but in rats which had been splenectomized there was a long-term suppression of the antibody response, which did not improve for at least one year. The results suggest that, in patients requiring splenectomy for trauma and not able to be vaccinated before operation, there may be no advantage in delaying prophylactic vaccination postoperatively.