biostudies-literatureUnknown32(3)Imbery JFChronic lymphocytic leukemia (CLL) growth is dependent on both B cell receptor (BCR) signaling and signals from microenvironmental T helper (Th) cells. We previously described a mechanism where Th cells enhance BCR signaling and proliferation through CD45 phosphatase activity regulation via galectin-1 and CD43. The CLL negative prognostic indicator CD38 is linked to BCR signaling and proliferation, with its expression induced by Th cells. Here, we explore a link between CD38 and CD45 phosphatase activity regulation using patient-derived material in a Th-CLL cell co-culture model. Results demonstrate CD43 and galectin-1 are co-expressed with CD38, defining proliferative CLL cells with augmented CD45 activity. CD38 enzymatic and receptor inhibition regulated CD43 and galectin-1 expression, CMolecular therapy. Oncology200841https://www.ebi.ac.uk/biostudies/studies/S-EPMC11519781biostudies-literatureCD38 regulates chronic lymphocytic leukemia proliferation via CD45 phosphatase activity.PMC11519781Bottini NImbery JFStanford SMWiik CDobbing MKHeinzelbecker JSzodoray PJebsen JKMunthe LANakken BTjonnfjord GETveita AfalseCD38 regulates chronic lymphocytic leukemia proliferation via CD45 phosphatase activity.Chronic lymphocytic leukemia (CLL) growth is dependent on both B cell receptor (BCR) signaling and signals from microenvironmental T helper (Th) cells. We previously described a mechanism where Th cells enhance BCR signaling and proliferation through CD45 phosphatase activity regulation via galectin-1 and CD43. The CLL negative prognostic indicator CD38 is linked to BCR signaling and proliferation, with its expression induced by Th cells. Here, we explore a link between CD38 and CD45 phosphatase activity regulation using patient-derived material in a Th-CLL cell co-culture model. Results demonstrate CD43 and galectin-1 are co-expressed with CD38, defining proliferative CLL cells with augmented CD45 activity. CD38 enzymatic and receptor inhibition regulated CD43 and galectin-1 expression, C2024-01-01T00:00:00Z2024 Sep2026-07-16T07:19:00.278Z2025-04-06T15:30:21.734ZS-EPMC115197813947460210.1016/j.omton.2024.200841