In situ identification of mononuclear cells infiltrating cutaneous carcinoma: an immuno-histochemical study.

The present study was undertaken in order to investigate the exact nature of the cells surrounding cutaneous tumours. Formalin-fixed, paraffin-embedded sections were tested with a horse antihuman T lymphocyte serum and with IgG, IgA and IgM rabbit antihuman serum. All the sections were respectively treated with rabbit anti-horse or swine antirabbit peroxidase-labelled serum. The advantages offered by the immunoperoxidase technique are briefly discussed. T cells are in overwhelming proportion in comparison with IgG, IgA and IgM bearing cells. This seems a further demonstration that mononuclear infiltrate surrounding cutaneous carcinoma mainly represents a cell-mediated immune response.