Impaired immune response of splenectomised patients to polyvalent pneumococcal vaccine.

Immune response to polyvalent pneumococcal vaccine was measured in normal volunteers and splenectomised patients, by means of a newly developed enzyme-linked immunosorbent assay for pneumococcal antibodies. IgG and IgM responses to eight of the nine polysaccharides tested were markedly impaired in splenectomised patients. The response of splenectomised patients was less than that of the controls in terms of absolute titre of antibody achieved, relative rise in titre (fold increase of post-immunisation titre over pre-immunisation titre), and rate of rise.