The Annals of Thoracic Surgery, Vol 31, 350-356, Copyright © 1981 by The Society of Thoracic Surgeons
Cell-mediated immunity is depressed following cardiopulmonary bypass
JA Roth, SH Golub, RA Cukingnan, J Brazier and DL Morton
Sequential in vitro lymphocyte function tests in 13 patients undergoing
cardiac operation were performed to determine factors that contribute to
depressed cell-mediated immunity following operation. Lymphocytes were
stimulated with phytohemagglutinin (PHA), pokeweed mitogen, concanavalin A
(Con A), and mitomycin-treated, pooled, allogeneic lymphocytes (MLC).
Mitogen responses were measured by 3H-labeled thymidine incorporation.
Circulating levels of T, B, and Fc-receptor lymphocytes were determined by
counting E, EAC, and EA rosettes. Serum cortisol was measured by
radioimmunoassay. The T-cell-dependent lymphocyte responses (PHA, Con A,
and MLC) were significantly decreased 24 hours after operation, and this
was accompanied by a 60% decrease in circulating T-cell levels. The PHA,
Con A, and MLC responses, and circulating T-cell levels returned to
preoperative values one week following operation. Lymphocyte responses to
mitogens remained significantly decreased when the number of T cells in the
postoperative cultures were adjusted to preoperative levels. This indicates
that the T cells remaining after operation were functionally impaired. We
conclude that lymphocyte proliferative responses and antigen recognition
are significantly depressed following cardiac operation, and that these
responses are related to decreased numbers of circulating T lymphocytes and
depressed function of the remaining T lymphocytes.
