{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T06:28:02Z","timestamp":1780468082362,"version":"3.54.1"},"reference-count":42,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2024,2,23]],"date-time":"2024-02-23T00:00:00Z","timestamp":1708646400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of KwaZulu-Natal productivity"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["CIMB"],"abstract":"<jats:p>Chronic lymphocytic leukemia (CLL) is characterized by dysfunctional B cells. Immune checkpoint molecules such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed death-1 (PD-1) are upregulated in patients with CLL and may correlate with prognostic markers such as beta-2 microglobulin (B2M). The aim of this study was to evaluate the levels of immune checkpoints on B cell subsets and to further correlate them with B2M levels in patients with CLL. We recruited 21 patients with CLL and 12 controls. B cell subsets and the levels of immune checkpoint expression were determined using conventional multi-color flow cytometry. Basal levels of B2M in patients with CLL were measured using an enzyme-linked immunosorbent assay. Patients with CLL had increased levels of activated B cells when compared to the control group, p &lt; 0.001. The expression of PD-1 and CTLA-4 were increased on activated B cells and memory B cells, p &lt; 0.05. There were no associations between B2M levels and the measured immune checkpoints on B cell subsets, after adjusting for sex and age. In our cohort, the patients with CLL expressed elevated levels of PD-1 and CTLA-4 immune checkpoints on activated and memory B cell subsets. However, there was no correlation between these immune checkpoint expressions and B2M levels.<\/jats:p>","DOI":"10.3390\/cimb46030112","type":"journal-article","created":{"date-parts":[[2024,2,23]],"date-time":"2024-02-23T10:47:30Z","timestamp":1708685250000},"page":"1731-1740","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["B Cell Subsets and Immune Checkpoint Expression in Patients with Chronic Lymphocytic Leukemia"],"prefix":"10.3390","volume":"46","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6658-6134","authenticated-orcid":false,"given":"Aviwe","family":"Ntsethe","sequence":"first","affiliation":[{"name":"School of Laboratory Medicine and Medical Sciences (SLMMS), University of KwaZulu-Natal, Durban 4000, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6877-3734","authenticated-orcid":false,"given":"Zekhethelo Alondwe","family":"Mkhwanazi","sequence":"additional","affiliation":[{"name":"School of Laboratory Medicine and Medical Sciences (SLMMS), University of KwaZulu-Natal, Durban 4000, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5965-3610","authenticated-orcid":false,"given":"Phiwayinkosi Vusi","family":"Dludla","sequence":"additional","affiliation":[{"name":"Cochrane South Africa, South African Medical Research Council, Tygerberg 7505, South Africa"},{"name":"Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa 3886, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bongani Brian","family":"Nkambule","sequence":"additional","affiliation":[{"name":"School of Laboratory Medicine and Medical Sciences (SLMMS), University of KwaZulu-Natal, Durban 4000, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"452","DOI":"10.3322\/caac.21577","article-title":"Cancer statistics for adults aged 85 years and older, 2019","volume":"69","author":"DeSantis","year":"2019","journal-title":"CA Cancer J. 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