Search for atypical lymphocytes in schizophrenia.

The existence of atypical lymphocytes with specific morphological characteristics in the peripheral blood of schizophrenic patients has been suggested in several reports over the last 40 years. In our study this observation was examined not only by using the formerly applied method of light microscopy for general cell distribution and lymphocyte morphology but also by applying flow cytometry, a well established immunological method for lymphocyte patterns such as lymphocyte subgroups and lymphocyte activity. In contrast to the previously published data, our results demonstrated no differences in cell distribution (lymphocytes, polymorphonuclear cells, eosinophil and basophil granulocytes, monocytes), lymphocyte morphology ("atypical lymphocytes" vs. "normal lymphocytes"), distribution of lymphocyte-subtypes (T-cells (CD3(+)), T-helper-cells (CD3(+)/CD4(+)), cytotoxic T-cells (CD3(+)/CD8(+)), B-cells (CD19(+)), NK-cells (CD3(-)/CD56(+))) or state of T-lymphocyte activity (CD25(+) or HLA-DR(+)-cells) in schizophrenic patients compared to healthy controls. We suggest that possible immunological alterations in schizophrenia do not correlate with morphological characteristics of lymphocytes observable by light microscopy or an altered state activity of T-lymphocytes examined by flow cytometric parameters. Further studies should concentrate on intracellular and functional aspects of the different lymphocyte subgroups.