PHENOTYPE AND PROLIFERATION CHARACTERISTICS OF CULTURED SPINDLE-SHAPED CELLS OBTAINED FROM NORMAL HUMAN SKIN AND LESIONS OF DERMATOFIBROMA,KAPOSIS-SARCOMA, AND DERMATOFIBROSARCOMA PROTUBERANS - A COMPARISON WITH FIBROBLAST AND ENDOTHELIAL-CELLS OF THE DERMIS

Normal human dermis contains mesenchymal cells that are generally refe rred to as fibroblasts. However the relationships between fibroblasts and endothelial cells with respect to the types of spindle-shaped cell s that are present in cultures obtained from tumor bearing-skin is unc lear. To explore the potential heterogeneity amongst dermal-derived ce lls that grow in culture with a spindle-shaped morphology, we compared the immunophenotype and growth characteristics of several types of ce lls. Besides dermal fibroblasts and microvascular endothelial cells de rived from normal adult skin, we also studied large vessel-derived end othelial cells, and spindle-shaped cells derived from three different tumor-bearing dermal-based neoplasms: Kaposi's sarcoma (KS), dermatofi broma (DF), and dermatofibrosarcoma protuberans (DFSP). A broad panel of eight different antibodies were used to immunophenotype the multi-p assaged cultured cells. Spindle-shaped cells from all three neoplasms could be distinguished from the normal skin derived fibroblasts by the ir constitutive expression of factor XIIIa, and the gamma-interferon i nduced expression of VCAM-1. All seven types of cultured cells stained positive for s-actin and proline-4-hydroxylase, and none of the cells expressed CD34. Both large and small-vessel derived endothelial cells expressed factor VIII, ELAM-1, and VCAM-1. Using two different types of growth media, significant differences were also observed amongst th ese cultured cell types. Spindle-shaped cells from DFSP did not grow i n DMEM containing 10% fetal bovine serum (DMEM-FBS); but they prolifer ated in KS cell growth medium (KSGM). Spindle-shaped cells from DF gre w best in KSGM, but not in DMEM-FBS. KS tumor cells grew well in KSGM, but not in DMEM-FBS. Fibroblasts proliferated in DMEM-FBS; but failed to grow in KSGM; and even when pre-treated with conditioned medium fr om a transformed KS cell line (i.e. SLK cells), no fibroblast prolifer ation could be induced in KSGM. These results indicate that KS cell li ne (i.e. SLK cells), no fibroblast proliferation could be induced in K SGM. These results indicate that even though dermal-derived cells can have an identical spindle-shape by light microscopy: significant heter ogeneity can be defined amongst such cells from normal and tumor-beari ng human skin. Having established culture conditions to propagate thes e different cell types and phenotypic criteria to distinguish them fro m one another, will provide new research opportunities to explore the function and ontogeny of the diverse mesenchymal cells that take on a spindle-shaped morphology in culture. (C) 1997 Elsevier Science Irelan d Ltd.