Cytotoxic T cells specific for human melanoma have been identified. We are interested in examining the nature of Fas expression on melanoma ceils to determine whether the interaction of this molecule with activated lymphoid populations contributes to the resultant immune response. To approach this issue, studies have been initiated to investigate the expression of Fas on human melanoma cell lines. These lines were established from tissue explants following surgery of patients in South Florida with metastatic lesions occurring in a variety of anatomical compartments and have been maintained in culture for at least 12 months. Utilizing CHll mab (anti-human Fas), we have identified melanoma lines which do (106.B7, 113} and do not (1-44.IL2, 147) constitutively express Fas antigen. To begin to assess if Fas expression can be induced and/or upregulated on these cells, cultures were incubated with varying levels of recombinant human IFN-gamma. Following 60-72 hours of exposure. Fas expression on 106.B7 can be upregulated in a dose dependent manner. Overall, the melanoma lines exhibited a range of responsiveness to IFN-gamma with respect to Fas and MHC expression. For example, IFN-gamma readily upregulated MHC class I but not Fas in melanoma line 113. However, other melanoma cells failed to respond to this cytokine as assessed by either Fas or MHC expression. We conclude that Fas and MHC in these melanoma lines are independently regulated in response to IFN-gamma. Studies are proposed to examine the functional consequences of stimulating Fas on these tumor cells.
|Original language||English (US)|
|State||Published - Dec 1 1996|
ASJC Scopus subject areas
- Molecular Biology