Decreased membrane potassium permeability and transport in human chronic leukemic and tonsillar lymphocytes

✍ Scribed by George B. Segel; Marshall A. Lichtman

• Publisher: John Wiley and Sons
• Year: 1977
• Tongue: English
• Weight: 877 KB
• Volume: 93
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1040930213

✦ Synopsis

Abstract

Human blood T‐lymphocytes increase their potassium (K^+^) permeability and active K^+^ transport following lectin or antigen stimulation. We have studied the permeability and active transport of K^+^ by lymphocytes in chronic lymphocytic leukemia (CLL) to determine if their membrane K^+^ transport was similar to resting or lectin‐stimulated normal blood lymphocytes. K^+^ transport was assessed both by the rate of isotopic ^42^K^+^ uptake and by the rate of change in cell K^+^ concentration after inhibition of the K^+^ transport system with ouabain.

CLL lymphocytes had a marked decrease in membrane K^+^ permeability and active transport of K^+^ when compared to blood T lymphocytes. K^+^ transport in five subjects with CLL (10 mmol. 1 cell water^−1^. h^−1^) was half that in normal blood T‐lymphocytes (20 mmol. 1 cell water^−1^ h^−1^). Phytohemagglutinin (PHA) treatment of CLL lymphocytes did not increase significantly their active K^+^ transport, whereas K^+^ transport by normal T‐lymphocytes increased by 100%.

Since there were 73% T‐lymphocytes in normal blood and 14% in CLL blood, the difference in membrane K^+^ turnover could be related either to neoplasia or to the proposed B‐lymphocyte origin of CLL. We studied human tonsillar lymphocytes which contained a mean of 34% T‐cells. In five studies of tonsils, K^+^ transport was 14 mmol. 1 cell water^−1^. h^−1^ and treatment with PHA increased K^+^ transport only 30%. The intermediate values for basal K^+^ transport and K^+^ transport in response to PHA in tonsillar lymphocytes were consistent with the proportion of T‐lymphocytes present. These data suggest that B‐lymphocytes have reduced membrane permeability and active transport of K^+^. Thus the marked decrease in CLL lymphocyte membrane K^+^ permeability and transport may be a reflection of its presumed B‐cell origin, rather than a membrane alteration related to malignant transformation.