Detecção dos marcadores CD200 e CD79b nas doenças linfoproliferativas crônicas de células B (DLPC-B): uma forte expressão na leucemia linfocítica crônica de células B (LLC-B)

Abstract

This study evaluated the expression of CD200 and CD79b markers in 795 patients with Chronic B-Cell Lymphoproliferative Diseases (B-LPDs), diagnosed between 2004 and 2022 at the Hemocentro of Rio Grande do Norte. The objective was to investigate the relevance of these markers in the diagnosis of B-LPDs. The analysis was performed using flow cytometry with a panel of monoclonal antibodies targeting these entities. The results showed that 69.7% of the investigated cases were positive for both markers. Among these, Chronic Lymphocytic Leukemia (CLL-B) was the most prevalent subtype, representing 61.26% of all cases. CLL-B presents a characteristic immunophenotype consisting of CD19+; CD5+; IgM+/IgD+, with strong CD200 positivity and negativity for FMC7 and CD79b in most cases. The weak expression of CD79b in CLL-B was a relevant factor for differential diagnosis, given its high positivity in other B-LPDs, such as follicular lymphoma (FL) and mantle cell lymphoma (MCL), further emphasizing the diagnostic utility of this marker. The expression of CD200 was also relevant for the differential diagnosis of the CLL-B immunophenotype from other entities, such as acute lymphoblastic leukemia (ALL). The findings reinforce the role of flow cytometry in differentiating between B-CLPD subtypes, demonstrating that the combination of CD200 and CD79b is a robust tool for differential diagnosis and prognosis. Furthermore, these markers show potential as therapeutic targets, especially in diseases such as CLL-B. It is concluded that the integrated analysis of these markers significantly contributes to the immunophenotypic characterization of B-CLPDs and the personalized management of patients.