Immunocytochemical analysis of the cellular infiltrate in primary regressing and non-regressing malignant melanoma.
Spontaneous regression occurs in a small proportion of malignant melanomas, and it is important to understand the processes involved in its induction as this may give a guide to future therapies for this disease. We have examined 36 primary malignant melanomas (19 regressing, 17 non-regressing) and identified the cellular phenotypes and activation states of the cells infiltrating regressing and non-regressing primary melanomas by immunochemistry. We have found a significantly increased number of CD3-positive cells and an increased ratio of CD4/CD8-positive cells infiltrating regressing compared to non-regressing tumors. In addition, the expression of the interleukin 2 receptor, an activation marker for T cells, was increased. However, there were no significant differences in class II MHC, CD1, intercellular adhesion molecule 1 (ICAM1), or melanoma-associated differentiation-antigen expression in these tumors. These data are consistent with melanoma regression being induced by activated CD4 T cells and do not seem to be related to the differentiation markers we have examined on these tumors.
Tefany
F J
FJ
Department of Dermatology, Royal Prince Alfred Hospital, Sydney, Australia.
Barnetson
R S
RS
Halliday
G M
GM
McCarthy
S W
SW
McCarthy
W H
WH
D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism; D000917:Antibody Formation / Q000276:immunology; D000938:Antigen-Presenting Cells / Q000276:immunology; D000951:Antigens, Neoplasm / Q000276:immunology / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D019041:L-Selectin; D007801:Langerhans Cells / Q000276:immunology / Q000378:metabolism; D008214:Lymphocytes / Q000276:immunology / Q000378:metabolism; D008545:Melanoma / Q000276:immunology / Q000378:metabolism* / Q000473:pathology
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D015815:Cell Adhesion Molecules; D019041:L-Selectin