In vivo and in vitro humoral immunity in surgical patients.

In vivo and in vitro humoral immunity was studied in surgical patients. Laboratory controls (LC), delayed type hypersensitivity (DTH) skin test reactive (HR), and anergic (HA) patients were immunized with tetanus toxoid. Maximum in vivo antibody levels occurred 14 days after immunization. Eighty-six, 47, and 17% of LC, HR, and HA subjects, respectively, showed a positive response (X2(2) = 21.1 with Yates, p less than 0.0005). Peak in vitro antibody production in unstimulated lymphocyte cultures occurred at day 6 after immunization. Antibody responses in vitro were reduced in all surgical patients, worst in HA, and correlated quantitatively with in vivo antibody responses at day 14 (Spearman rank correlation = 0.794, p less than 0.001). Total IgG production in vitro was not decreased; 595, 1080, and 1538 ng IgG/culture were produced by LC, HR, and HA, respectively. These data demonstrate decreased in vivo and in vitro humoral immunity in all surgical patients, worst in those with decreased DTH responses. There is a kinetic and quantitative correlation between in vivo and in vitro responses, the latter being a biologic reflection of the integrity and magnitude of the in vivo process. Finally, failure to produce specific antibody is not due to failure of total IgG synthesis.