title: Expression of CD45 isoforms in fresh and IL-2-cultured tumor-infiltrating lymphocytes from basal cell carcinoma.
abstract: Immunohistochemistry and flow cytometry analyses were performed to characterize the specific T cell subpopulations infiltrating basal cell carcinomas (BCC) and to determine their phenotypic response to in vitro expansion with IL-2. Tumor-infiltrating lymphocytes (TIL) within BCC predominantly expressed the CD45RO (activated or "memory") phenotype (65 +/- 3%) and the percentage of TIL expressing CD45RO consistently increased when cultured in vitro with IL-2 (85 +/- 5%). In comparison, fresh normal peripheral blood lymphocytes predominantly expressed the CD45RA (naive) phenotype (79 +/- 4%), but shifted to the expression of CD45RO following in vitro expansion in IL-2 (86 +/- 6%). To determine whether IL-2 alone, in the absence of antigen or mitogen, can promote naive lymphocytes to convert from the expression of the CD45RA isoform to the CD45RO isoform, we cultured purified CD45RA+ lymphocytes in IL-2. After three weeks in culture, 90% of the lymphocytes expressed exclusively CD45RO. We conclude that tumor-infiltrating lymphocytes from BCC predominantly express CD45RO and that this expression may represent specific antigen stimulation and/or in situ activation by cytokines.
authors.affiliation: Division of Dermatology, UCLA School of Medicine 90024.
authors.forename: Q H
authors.initials: QH
authors.lastname: Nguyen
authors.forename: R L
authors.initials: RL
authors.lastname: Moy
authors.forename: M D
authors.initials: MD
authors.lastname: Roth
authors.forename: R
authors.initials: R
authors.lastname: Yamamoto
authors.forename: S
authors.initials: S
authors.lastname: Tomono
authors.forename: S M
authors.initials: SM
authors.lastname: Dubinett
mesh_terms: D000328:Adult; D002280:Basal Cell Carcinoma / Q000276:immunology*; D002469:Cell Separation; D002478:Cells, Cultured; D005434:Flow Cytometry; D006801:Humans; D007124:Immunoenzyme Techniques; D016130:Immunophenotyping; D007376:Interleukin-2 / Q000494:pharmacology*; D017493:Leukocyte Common Antigens / Q000096:biosynthesis*; D016246:Lymphocytes, Tumor-Infiltrating / Q000187:drug effects / Q000276:immunology*
chemical_list: D007376:Interleukin-2; D017493:Leukocyte Common Antigens