Human renal-cell carcinoma tissue contains dendritic cells.
Immune surveillance of cancer requires antigen-presenting cells which activate T cells specific for tumor-associated antigens. We show here that substantial numbers of dendritic cells, which are the most potent antigen-presenting cells, emigrate from renal-tumor explants in organ culture. Tumor-derived dendritic cells presented with all characteristics of mature dendritic cells. Dendritic cells could be identified by typical cytoplasmic projections (=veils). They expressed high levels of MHC products and of the co-stimulator CD86 (B7-2). Dendritic cells expressed the CD45RO isoform but not CD45RA. The most important point was that up to 9% of the emigrating leukocytes expressed the CD83 antigen, a specific marker for mature dendritic cells. CD83+ cells were approximately 40-fold enriched in the tumor tissue as compared to the peripheral blood. In contrast to cultured blood dendritic cells, tumor-emigrant dendritic cells had a reduced potential to capture soluble antigen, as shown by the exclusion of fluoresceinated Dextran molecules. Finally, in mixed leukocyte reactions, tumor-derived dendritic cells were able to stimulate naive T cells from cord blood, which is a unique feature of dendritic cells. This study demonstrates that genuine dendritic cells reside in or infiltrate renal-cell carcinoma tissue. The failure of patients with renal-cell carcinoma to mount an anti-tumor immune response despite the presence of professional antigen-presenting cells in the tumor tissue suggests that tumor-associated dendritic cells are suppressed in situ, in a similar way to that described for tumor-infiltrating lymphocytes.
Department of Urology, University of Innsbruck, Austria.
M
M
Thurnher
C
C
Radmayr
R
R
Ramoner
S
S
Ebner
G
G
Böck
H
H
Klocker
N
N
Romani
G
G
Bartsch
D015703:Antigens, CD; D000955:Antigens, T-Independent; D002292:Carcinoma, Renal Cell / Q000276:immunology / Q000473:pathology*; D003713:Dendritic Cells / Q000276:immunology / Q000473:pathology*; D003911:Dextrans; D004705:Endocytosis; D005434:Flow Cytometry; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D016130:Immunophenotyping; D007680:Kidney Neoplasms / Q000276:immunology / Q000473:pathology*; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology / Q000473:pathology; D008562:Membrane Glycoproteins / Q000032:analysis; D009924:Organ Culture Techniques; D013601:T-Lymphocytes / Q000276:immunology; D014407:Tumor Cells, Cultured; D000097802:CD83 Antigen
D015703:Antigens, CD; D000955:Antigens, T-Independent; D003911:Dextrans; D016650:Fluorescein-5-isothiocyanate; D007136:Immunoglobulins; D008562:Membrane Glycoproteins; D000097802:CD83 Antigen; C015219:fluorescein isothiocyanate dextran