title: Interferon-gamma induces persistent depletion of internal Ca2+ stores in a human salivary gland cell line.
abstract: Interferon-gamma (IFN-gamma), in the presence of tumor necrosis factor-alpha (TNF-alpha), decreases proliferation of a human salivary gland ductal cell line, HSG (Wu, A., R. Kurrasch, J. Katz, P. Fox, B. Baum, and J. Atkinson. J. Cell. Physiol. 161:217-226, 1994). We examined the possible effects of these cytokines (1,000 U/ml IFN-gamma +/- 20 U/ml TNF-alpha for 7 days) on Ca2+ mobilization in HSG cells. In HSG cells, fetal bovine serum (10%) or carbachol (100 microM) stimulated rapid increases in cytosolic Ca2+ concentration ([Ca2+]i), apparently mobilized from different thapsigargin-sensitive intracellular Ca2+ stores. Serum induced a proliferative effect on HSG cells, which was suppressed (> 90%) by treatment with IFN-gamma +/- TNF-alpha, but not with TNF-alpha alone. Serum-, carbachol-, and thapsigargin-stimulated [Ca2+]i elevations were reduced by 90, 60, and > 65%, respectively, in cells treated with IFN-gamma +/- TNF-alpha and 30, 45, and 45%, respectively, in cells treated with TNF-alpha. Removal of the cytokines from the growth medium induced recovery of both cell proliferation and Ca2+ mobilization responses within 7 days. Treatment of HSG cells with thapsigargin (0.02-2 nM) induced a dose-dependent decrease in cell proliferation. Additionally, acute treatment (< 10 min) of cells with IFN-gamma did not affect [Ca2+]i or alter carbachol-, thapsigargin-, or serum-induced changes in [Ca2+]i. These data demonstrate that prolonged treatment of HSG cells with IFN-gamma +/- TNF-alpha leads to a persistent depletion of intracellular Ca2+ stores. We suggest that this may have a role in cell growth.
authors.affiliation: Clinical Investigations and Patient Care Branch, National Institute of Dental Research, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: A J
authors.initials: AJ
authors.lastname: Wu
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Chen
authors.forename: B J
authors.initials: BJ
authors.lastname: Baum
authors.forename: I S
authors.initials: IS
authors.lastname: Ambudkar
mesh_terms: D001790:Blood Physiological Phenomena; D002118:Calcium / Q000037:antagonists & inhibitors*; D000252:Calcium-Transporting ATPases / Q000037:antagonists & inhibitors; D002217:Carbachol / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D012469:Salivary Glands / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D019284:Thapsigargin / Q000494:pharmacology; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D014409:Tumor Necrosis Factor-alpha; D019284:Thapsigargin; D007371:Interferon-gamma; D002217:Carbachol; D000252:Calcium-Transporting ATPases; D002118:Calcium