[The effect of craniotomy on lymphocyte subpopulations]

The effect of craniotomy on cell mediated immunity was studied by using monoclonal antibodies and flow cytometry. Twelve patients undergoing craniotomy were investigated. Six patients had malignant brain tumor, four benign tumor, one AVM and one aneurysm. Examined lymphocyte monoclonal antibodies were Leu4, Leu2a and Leu3a. In addition, two color analysis using two monoclonal antibodies, Leu3a and Leu8, or Leu2a and Leu15, was performed. This technique can classify Leu3a positive cell into helper T cell and inducer T cell and Leu2a positive cell into suppressor T cell and cytotoxic T cell. The number of Leu4 positive cell (T cell) decreased during operation. The number of Leu3a positive cell (OKT4) also decreased at 30 minutes after incision and moderately recovered during operation. Leu2a positive cell (OKT8) did not show significant change. As the result, the decline of Leu3a/Leu2a ratio (OKT4/OKT8 ratio) was found after incision and this ratio gradually returned to preoperative level during operation. By two color analysis, decrease of inducer and helper T cell in Leu3a positive cell, and increase of suppressor T cell, and decrease of cytotoxic T cell in Leu2a positive cell were observed. The results of this study show that stress of craniotomy affected the immunological state.