In B chronic lymphocytic leukemia (B-CLL) cells, lipopolysaccharide (LPS) and phorbol esters fail to activate the plasma membrane-associated Na+/H+ antiporter and, subsequently, to elicit a rise in cytosolic pH. Since these events are thought to be a prerequisite for LPS-induced proliferation of B normal lymphocytes, we analyzed the kinetic properties of Na+/H+ antiporter in B-CLL cells as compared to both CD5- and CD5+ normal B lymphocytes. In the present work we report that Na+/H+ exchange rate after acid loading is drastically decreased in B-CLL cells, as compared to normal CD5- B lymphocytes, although the antiporter affinity for external Na+ and internal H+ is not significantly different in both cell populations. Kinetic data account for a reduction in the number of operating antiport units in B-CLL. The Na+/H+ antiporter of CD5+ normal B lymphocytes exhibits both an exchange rate and an ion affinity significantly higher than that observed in both CD5+ B-CLL cells and CD5- B normal lymphocytes, thus suggesting a possible explanation for their activated phenotype.

Na+/H+ antiporter has different properties in human B lymphocytes according to CD5 expression and malignant phenotype. / GHIGO D ;GAIDANO G ;TREVES S ;BUSSOLINO F ;PESCARMONA G ;CALIGARIS-CAPPIO F ;BOSIA A. - In: EUROPEAN JOURNAL OF IMMUNOLOGY. - ISSN 0014-2980. - 21(1991), pp. 583-588.

Na+/H+ antiporter has different properties in human B lymphocytes according to CD5 expression and malignant phenotype.

GHIGO, Dario Antonio;BUSSOLINO, Federico;PESCARMONA, Gianpiero;BOSIA, Amalia
1991

Abstract

In B chronic lymphocytic leukemia (B-CLL) cells, lipopolysaccharide (LPS) and phorbol esters fail to activate the plasma membrane-associated Na+/H+ antiporter and, subsequently, to elicit a rise in cytosolic pH. Since these events are thought to be a prerequisite for LPS-induced proliferation of B normal lymphocytes, we analyzed the kinetic properties of Na+/H+ antiporter in B-CLL cells as compared to both CD5- and CD5+ normal B lymphocytes. In the present work we report that Na+/H+ exchange rate after acid loading is drastically decreased in B-CLL cells, as compared to normal CD5- B lymphocytes, although the antiporter affinity for external Na+ and internal H+ is not significantly different in both cell populations. Kinetic data account for a reduction in the number of operating antiport units in B-CLL. The Na+/H+ antiporter of CD5+ normal B lymphocytes exhibits both an exchange rate and an ion affinity significantly higher than that observed in both CD5+ B-CLL cells and CD5- B normal lymphocytes, thus suggesting a possible explanation for their activated phenotype.
21
583
588
GHIGO D ;GAIDANO G ;TREVES S ;BUSSOLINO F ;PESCARMONA G ;CALIGARIS-CAPPIO F ;BOSIA A
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/2318/32143
Citazioni
  • ???jsp.display-item.citation.pmc??? 1
  • Scopus ND
  • ???jsp.display-item.citation.isi??? 12
social impact