Engagement of Na,K-ATPase beta3 subunit by a specific mAb suppresses T and B lymphocyte activation

Abstract

In order to identify new molecules involved in regulation of T cell proliferation, we generated various mAb by immunization of mice with the T cell line Molt4. We found one mAb (termed P-3E10) that down-regulated the in vitro T cell proliferation induced by CD3-specific OKT3 mAb. The P-3E10 mAb was also able to inhibit IFN-gamma, IL-2, IL-4 and IL-10 production of OKT3-activated T cells. The antigen recognized by P-3E10 mAb is broadly expressed on all hematopoietic as well as on all non-hematopoietic cell lines tested so far. Within peripheral blood leukocytes, the P-3E10 antigen was detected on lymphocytes, monocytes and granulocytes. Human umbilical vein endothelial cells (HUVEC) also scored positively. By evaluating the effect of P-3E10 mAb on these cell types we found that it also inhibited anti-IgM-induced B cell proliferation. However, it did not block growth factor-mediated proliferation of HUVEC, and spontaneous proliferation of SupT-1, Jurkat, Molt4 and U937 cell lines. Moreover, it did not influence phagocytosis of human blood monocytes and granulocytes. Biochemical analysis revealed that the P-3E10 antigen is a protein with a mol. wt of 45-50 kDa under non-reducing and 50-55 kDa under reducing conditions. By using a retroviral cloning system, the P-3E10 antigen was cloned. Sequence analysis revealed the P-3E10 antigen to be identical to the beta3 subunit of the Na,K-ATPase.

New Insights into the DT40 B Cell Receptor Cluster Using a Proteomic Proximity Labeling Assay

“…However, a monoclonal antibody specific for the β3 subunit of the Na,K-ATPase inhibits mitogen activation of both T- and B-lymphocytes (62). Another interesting protein identified by SPPLAT was Evi2a.…”

P2C-Type ATPases and Their Regulation

“…The reported reduction of the β2 isoform in glioblastomas is interesting because this could be the factor that initiates invasion by these cells [42]. Inactivation of the β3 isoform can inactivate T and B lymphocytes, which is important for immune regulation [9].…”

“…Na + /K + -ATPase uses almost 30 % of the ATP available to the cell and has important roles that include the following: (1) maintaining ionic balance, (2) providing energy through the coupled transport of nutrients, (3) re-establishing the ionic gradient after an action potential in neurons, (4) helping to maintain a gradient in epithelial cells, and (5) activating lymphocytes [9].…”

ATP1B3: a virus-induced host factor against EV71 replication by up-regulating the production of type-I interferons

“…The 43-kDa ATP1B3, a β-subunit of Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/yviro ATPase, is localized to the q22-4 23 region of Chromosome (Chr) 3 (Besirli et al, 1998;Malik et al, 1998). Previous studies have demonstrated that ATP1B3 can up-regulate lymphocyte activity and promote the production of IFN-γ, IL-2, IL-4, and IL-10 (Chiampanichayakul et al, 2002) (Chruewkamlow et al, 2015). However, whether ATP1B3 can mediate the innate immune responses during EV71 infection is largely unknown.…”