Multiple mechanisms of immune evasion within transformed KC have been described including Fas down-regulation [8, 9], downstream effects on apoptosis of down-regulation of the retinoblastoma gene [10], alteration of the processing of IFNγ -dependent intracellular proteins [11, 12, 13], and changes to the TNF receptor and processing [14]. The gene discussed is FAS; the disease is keratoconus.