BACKGROUND: Bicarbonate transport has crucial roles in regulating intracellular pH (pHi) in a variety of cells. The purpose of this study was to evaluate its participation in the regulation of pHi in resting and stimulated human neutrophils. METHODS: Freshly isolated human neutrophils acidified by an ammonium prepulse were used in this study. RESULTS: We demonstrated that resting neutrophils have a bicarbonate transport mechanism that prevents acidification when the Na(+)/H(+) exchanger is blocked by EIPA. Neutrophils acidified by an ammonium prepulse showed an EIPA-resistant recovery of pHi that was inhibited by the blocker of the anionic transporters SITS or the Na(+)/HCO3(-) cotransporter (NBC) selective inhibitor S0859, and abolished when sodium was removed from the extracellular medium. In western blot and RT-PCR analysis the expression of NBCe2 but not NBCe1 or NBCn1 was detected in neutrophils Acidified neutrophils increased the EIPA-insensitive pHi recovery rate when its activity was stimulated with fMLF/ cytochalasin B. This increase in the removal of acid equivalents was insensitive to the blockade of the NADPH oxidase with DPI. CONCLUSION: It is concluded that neutrophils have an NBC that regulates basal pHi and is modulated by chemotactic agents.
BACKGROUND:Bicarbonate transport has crucial roles in regulating intracellular pH (pHi) in a variety of cells. The purpose of this study was to evaluate its participation in the regulation of pHi in resting and stimulated human neutrophils. METHODS: Freshly isolated human neutrophils acidified by an ammonium prepulse were used in this study. RESULTS: We demonstrated that resting neutrophils have a bicarbonate transport mechanism that prevents acidification when the Na(+)/H(+) exchanger is blocked by EIPA. Neutrophils acidified by an ammonium prepulse showed an EIPA-resistant recovery of pHi that was inhibited by the blocker of the anionic transporters SITS or the Na(+)/HCO3(-) cotransporter (NBC) selective inhibitor S0859, and abolished when sodium was removed from the extracellular medium. In western blot and RT-PCR analysis the expression of NBCe2 but not NBCe1 or NBCn1 was detected in neutrophils Acidified neutrophils increased the EIPA-insensitive pHi recovery rate when its activity was stimulated with fMLF/ cytochalasin B. This increase in the removal of acid equivalents was insensitive to the blockade of the NADPH oxidase with DPI. CONCLUSION: It is concluded that neutrophils have an NBC that regulates basal pHi and is modulated by chemotactic agents.
Authors: S Denk; R P Taylor; R Wiegner; E M Cook; M A Lindorfer; K Pfeiffer; S Paschke; T Eiseler; M Weiss; E Barth; J D Lambris; M Kalbitz; T Martin; H Barth; D A C Messerer; F Gebhard; M S Huber-Lang Journal: Scand J Immunol Date: 2017-09 Impact factor: 3.487
Authors: John J Gildea; Peng Xu; Julia M Carlson; Robert T Gaglione; Dora Bigler Wang; Brandon A Kemp; Camellia M Reyes; Helen E McGrath; Robert M Carey; Pedro A Jose; Robin A Felder Journal: Am J Physiol Regul Integr Comp Physiol Date: 2015-10-07 Impact factor: 3.619
Authors: Stefan Bernhard; Stefan Hug; Alexander Elias Paul Stratmann; Maike Erber; Laura Vidoni; Christiane Leonie Knapp; Bertram Dietrich Thomaß; Michael Fauler; Bo Nilsson; Kristina Nilsson Ekdahl; Karl Föhr; Christian Karl Braun; Lisa Wohlgemuth; Markus Huber-Lang; David Alexander Christian Messerer Journal: J Innate Immun Date: 2021-04-15 Impact factor: 7.349
Authors: Christian Maueröder; Aparna Mahajan; Susanne Paulus; Stefanie Gößwein; Jonas Hahn; Deborah Kienhöfer; Mona H Biermann; Philipp Tripal; Ralf P Friedrich; Luis E Munoz; Markus F Neurath; Christoph Becker; Georg Andreas Schett; Martin Herrmann; Moritz Leppkes Journal: Front Immunol Date: 2016-12-09 Impact factor: 7.561