Human leukocyte class I antigen and beta2-microglobulin expression in conjunctival dysplasia, carcinoma in situ, and squamous cell carcinoma.

Purpose: Malignant transformation of cells is frequently associated with abnormalities in HLA expression. These abnormalities may play a significant role in the clinical course of the disease because the cellular immune response to tumors relies on concomitant recognition of tumor antigens with self-HLA molecules. Since HLA molecules mediate interactions of tumor cells with specific receptors on T and natural killer (NK) cells, tight control of expression of HLA molecules is critical for initiation and implementation of an effective cellular immune response.