Presence and specificity of tumor associated lymphocytes from ascites fluid in prostate cancer.
BACKGROUND
In the present study, we had the rare opportunity to study immunological responses of TAL from ascites fluid in a patient with hormone-refractory prostate cancer.


METHODS
We evaluated tumor antigen-specific T-cell responses, induced by either prostate specific antigen (PSA) pulsed dendritic cells (DCs) or PSA peptides, in TAL and peripheral blood lymphocytes.


RESULTS
DC stimulation with PSA protein induced recognition of naturally processed PSA epitopes by both blood and ascites T cells. In contrast, only ascites T cells recognized the PSA-3 peptide, after stimulation with PSA-pulsed DCs or peptides. Finally, although IFNgamma secreting T cells were detectable in both blood and ascites by ELISPOT, multiplex cytokine assay detected the presence of predominantly Th2 cytokines.


CONCLUSIONS
Although tumor antigen-specific TAL were detected in ascites fluid, these cells were producing immunosuppressive cytokines which may contribute to tumor escape from recognition and/or destruction by the immune system.
Ozenci
Volkan
V
Immune and Gene Therapy Laboratory, Cancer Centre Karolinska, Karolinska Institute, Stockholm, Sweden.
Miller
Ashley M
AM
Palmborg
Andreas
A
Egevad
Lars
L
Jaremko
Georg A
GA
Kälkner
Karl Mikael
KM
Pisa
Pavel
P
D001202:Ascitic Fluid / Q000166:cytology / Q000276:immunology*; D016207:Cytokines / Q000032:analysis; D018984:Epitopes, T-Lymphocyte; D006801:Humans; D018793:Interleukin-13 / Q000502:physiology; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000276:immunology*; D011471:Prostatic Neoplasms / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D016207:Cytokines; D018984:Epitopes, T-Lymphocyte; D018793:Interleukin-13; D017430:Prostate-Specific Antigen