Summary:
Heterogeneous expression of HLA-D antigens has been reported in about one half of all primary malignant melanomas. HLA-D positive phenotype of melanomas seems to be associated with poor prognosis, however, the questions regarding their exact biological role and changes during the course of disease remain unanswered. The stability of HLA-D antigen expression in the course of disease progression was investigated in this study using immunohistochemical detection with CR3/43 anti-HLA-D monoclonal antibody and APAAP technique. The material consisted of 72 sequential biopsies of primary melanoma, nodal and subcutaneous distant metastases from 19 patients followed for several years until the death. HLA-D antigens were expressed in 52,6 % in primary tumors, but only in 21,1 % and 23,5 % in nodal and subcutaneous metastases respectively. This decrease of HLA-D antigen expression in metastases is broadly discussed in the context of dualistic role of HLA-D antigens as immunoregulatory molecules as well as their changing occurence during melanoma cell differentiation.
HLA-D antigens and the progress of malignant melanoma
