Epidermis and thymus. similar antigenic properties in hassall's corpuscle and subsets of keratinocytes

Using human sera obtained from bone marrow transplant recipients which contain antibodies to cytoplasmic epidermal antigens, we have found a cross reactivity between epidermis and thymus in immunofluorescence. The shared antigen(s) were only localized in the Hassall's corpuscle on the thymus and the upper (stratum spinosum) compartment of the epidermis. The basal cell layer did not show shared antigens. Antigenic similarity between epidermis and thymus may thus be restricted to a subset of keratinocytes.