Neurosurgical stress and immune function.

The present study was carried out in 31 neurosurgical patients with unaffected consciousness and concerned by the severity of their condition. The severity of stress was established by the comparison between the pre- and postoperative peripheral blood lymphocyte populations and subpopulations (B, T, Th lymphocytes, serum complement and circulating immune complexes). The peripheral blood lymphocyte populations and subpopulations were determined by the technique of sheep red blood cell rosette. Circulating immune complexes were determined by precipitation of polyethylene glycol (PEG, M = 6000) whereas the serum complement by the usual 50% hemolytic method. Our data show that the decrease in Th cells and the consecutive diminution of antibody production is a cause of lower resistance against cancer and infections.