VIRUS-INDUCED INCREASES IN BRONCHIOLAR MAST-CELLS IN BROWN-NORWAY RATS ARE ASSOCIATED WITH BOTH LOCAL MAST-CELL PROLIFERATION AND INCREASESIN BLOOD MAST-CELL PRECURSORS

Citation
Sd. Sorden et Wl. Castleman, VIRUS-INDUCED INCREASES IN BRONCHIOLAR MAST-CELLS IN BROWN-NORWAY RATS ARE ASSOCIATED WITH BOTH LOCAL MAST-CELL PROLIFERATION AND INCREASESIN BLOOD MAST-CELL PRECURSORS, Laboratory investigation, 73(2), 1995, pp. 197-204
Citations number
53
Categorie Soggetti
Pathology,"Medicine, Research & Experimental
Journal title
ISSN journal
00236837
Volume
73
Issue
2
Year of publication
1995
Pages
197 - 204
Database
ISI
SICI code
0023-6837(1995)73:2<197:VIIBMI>2.0.ZU;2-K
Abstract
BACKGROUND: Parainfluenza type 1 (Sendai) virus-induced bronchiolitis during early life in rats induces increases in bronchiolar mast cells that persist for months after infection and are associated with airway obstruction and airway hyperresponsiveness. frown Norway (BN) rats ar e highly susceptible, and Fischer 344 (F344) rats are relatively resis tant to, Sendai virus-induced increases in airway responsiveness and m ast cell density. EXPERIMENTAL DESIGN: To identify mechanisms responsi ble for the virus-induced mast cell increases, BN rats were studied us ing in vivo bromodeoxyuridine labeling, in vitro culture of bone marro w, blood, and lung mast cell progenitors (colony-forming unit-mast cel l (CFU-MC)), and in vivo treatment with the rodent mast cell stabilize rs disodium cromoglycate and nedocromil sodium. Bone marrow, blood, an d lung CFU-MC were also quantitated in F344 rats. RESULTS: At 10 days after inoculation, there was a fivefold increase (p = 0.001) in the br omodeoxyuridine labeling index of bronchiolar mast cells in virus-inoc ulated BN rats. Viral inoculation increased CFU-MC/ml blood greater th an fivefold (p < 0.05) in BN rats at 10 days after inoculation, and BN rats had greater numbers of both blood and lung CFU-MC than did F344 rats. Treatment with inhibitors of mast cell degranulation had no effe ct on Sendai virus-induced bronchiolar mast cell increases in BN rats. CONCLUSIONS: Virus-induced increases in bronchiolar mast cells result from proliferation of preexisting mast cells and may be augmented by recruitment of circulating mast cell precursors.