Expression of CD3-zeta on T-cells in primary cervical carcinoma and in metastasis-positive and -negative pelvic lymph nodes

Lymphocytic infiltrate is often present in cervical cancer lesions, possibl y reflecting an ongoing, but ineffective, immune response to the tumour. Re cently, evidence has accumulated for systemically impaired T-cell functions in cancer patients, associated with decreased expression of signal-transdu cing zeta (zeta) chain dimer molecules on circulating T-cells and NK-cells. Here, we report on the intralesional downregulation of zeta chain expressi on on T-cells in cervical carcinoma. Paraffin-embedded or snap-frozen secti ons from 24 different cervical cancer specimens were studied. Paraffin-embe dded tumour-positive (n = 7) and tumour-negative (n = 15) pelvic lymph node s were also included in the study. Immunostaining was performed on consecut ive sections with antibodies specific for CD3-epsilon or the CD3-associated zeta chain dimer. Antigen retrieval by sodium citrate/microwave treatment was essential for zeta staining of paraffin sections. The amount of zeta po sitive cells was quantitated and related to the number of CD3-epsilon+ cell s in corresponding tumour areas. Of the 24 cervical cancer specimens studie d, zeta chain dimer expression was reduced in seven cases and strongly redu ced in the other 17 samples. In tonsil control sections, CD3-epsilon and CD 3-zeta were always co-expressed in almost equal numbers. Also, both tumour- negative and -positive lymph nodes showed zeta chain expression which equal led that of CD3-epsilon expression. These data indicate that a decreased ex pression of signal-transducing zeta molecules on tumour-infiltrating T-cell s is frequent in cervical cancer. The apparently unimpaired zeta chain expr ession within draining lymph nodes suggests that local tumour-derived facto rs at the primary site are instrumental in zeta chain down-regulation.