title: Enhancement of production of superoxide anion by human polymorphonuclear leukocytes exposed to products of the HT-29 human colonic adenocarcinoma cell line.
abstract: Generation of superoxide anion (O2-) by human polymorphonuclear leukocytes (PMNs) in response to stimulation by opsonized zymosan was enhanced about 100% by prior exposure of the PMNs to human colonic adenocarcinoma cells (HT-29 cell line) or their conditioned culture medium. In addition, HT-29 cells produced substances that had an appreciable chemokinetic activity on PMNs. These tumor-secreted substances appeared to act directly on the PMNs rather than indirectly by interacting with nonadherent mononuclear cells, e.g., lymphocytes. Such a priming activity to display enhanced production of O2- was also found in conditioned medium from F344 rat FR3T3 embryonic fibroblasts but not in conditioned medium from HT-29 repolarized cells (by culture in galactose-containing medium) or from nontumorous human colonic mucosa explants. Such active substances may be important in the host-tumor relationship and, therefore, in the outcome of tumor growth.
mesh_terms: D000230:Adenocarcinoma / Q000276:immunology / Q000378:metabolism*; D000818:Animals; D002460:Cell Line; D002465:Cell Movement; D003110:Colonic Neoplasms / Q000276:immunology / Q000378:metabolism*; D003470:Culture Media; D006801:Humans; D007700:Kinetics; D008214:Lymphocytes / Q000502:physiology; D009504:Neutrophils / Q000378:metabolism*; D010084:Oxidation-Reduction; D010587:Phagocytosis; D051381:Rats; D011916:Rats, Inbred F344; D013481:Superoxides / Q000378:metabolism*
chemical_list: D003470:Culture Media; D013481:Superoxides