Cellular acid-base status has been found to exert selective actions on the effector functions of activated macrophages (mphi). We examined the effects of extracellular pH (pH(o)) on the production of @entity5 @entity39 factor-alpha ( @entity25229 ) induced by lipopolysaccharide (LPS) in resident alveolar mphi. Cells were obtained by bronchoalveolar lavage of @entity95 , activated in vitro with LPS, and cultured at pH(o) 5.5, 6.5 or 7.4 for up to 18 h. The relative abundance of @entity25229 mRNA peaked at approximately 2 h. The peak transcript abundance was increased at lower pH(o) values. This finding probably reflected pre-transcription/transcription effects of pH, in as much as the stability of @entity25229 mRNA induced with @entity4621 was unaffected by the experimental pH(o) values. @entity25229 secretion by LPS-treated mphi decreased at lower pH(o) values. The @entity25229 content of mphi-conditioned media decreased progressively with decrements in pH(o). The reduced @entity25229 secretion at pH(o) 5.5 was accompanied by an increase in the cytosolic @entity25229 content (compared with that at pH(o) 7.4), indicating that pH(o) altered @entity25229 secretion due, in part, to the intracellular retention of synthesized cytokine (i.e. a post-translation effect). The data show that pH(o) has multiple effects (pre-transcription/transcription and post-translation) on @entity25229 production induced by LPS in resident alveolar mphi. These results suggest that the role of alveolar mphi in inflammatory responses is modulated by pH(o), which may be important in @entity5 /abscesses and sites of infection where the external milieu is acidic.

Effects of extracellular pH on XXXX @entity39 factor-alpha production by resident alveolar macrophages.

@entity25229 :: ('100009088(Tax:9986)', 'Gene') :: ['TNF-alpha'] @entity39 :: ('MESH:D009336', 'Disease') :: ['necrosis'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumour', 'tumours'] @entity95 :: ('9986', 'Species') :: ['rabbits'] @entity4621 :: ('CHEBI:37532', 'Chemical') :: ['phorbol ester']
@entity5 :: (MESH:D009369,Disease) :: ['tumour']
