Suppressed colony formation of peripheral blood lymphocytes in a patient with somatostatinoma.
The in vitro clonal growth of T lymphocytes was examined in a patient with somatostatinoma over a period of 8 months. After phytohemagglutinin stimulation colony-forming unit T lymphocytes could not be detected as compared to healthy controls and patients with metastatic colon tumors. The somatostatin produced by this tumor was identified as somatostatin-14. Synthetic somatostatin-14 inhibits significantly the colony formation and the tritiated thymidine incorporation of human peripheral T lymphocytes obtained from healthy subjects, suggesting immunoregulative properties of this neuroendocrine peptide.
D007516:Adenoma, Islet Cell / Q000276:immunology*; D003110:Colonic Neoplasms / Q000276:immunology*; D006801:Humans; D007958:Leukocyte Count; D008213:Lymphocyte Activation; D013004:Somatostatin / Q000502:physiology*; D013005:Somatostatinoma / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D013004:Somatostatin