Cytometry Part B: Clinical Cytometry最新文献

To analyze the immunophenotypic characteristics of plasma cells in patients with polyneuropathy, organomegaly, endocrinopathy, myeloma protein, and skin changes (POEMS) syndrome. This retrospective study included patients with POEMS syndrome hospitalized in the Department of Hematology, Huashan Hospital, from September 2017 to August 2025. Demographic data, clinical features, flow cytometry results, and bone marrow morphological findings were analyzed. A total of 69 POEMS syndrome patients (44 males, 25 females; median age 54 years) were included. Flow cytometry detected monoclonal plasma cells in 63.77% (44/69) of patients, with higher plasma cell proportions in cases with detectable monoclonal plasma cells group (p = 0.003). The nine-color flow cytometry protocol demonstrated a significantly higher detection rate of monoclonal plasma cells compared to the six-color protocol (77.42% vs. 52.63%, p = 0.033). Immunophenotypic analysis revealed 100% expression of CD38 and CD138, with higher expression of CD27, CD28, CD117, and CD81 in POEMS patients compared to multiple myeloma patients (all p < 0.05). Bone marrow morphology showed higher plasma cell proportions in the abnormal group (p = 0.01). With additional fluorescent channels and enhanced detection sensitivity offering simultaneous analysis of multiple surface markers and intracellular light chains (κ/λ), nine-color flow cytometry enables more precise identification of abnormal plasma cells in POEMS syndrome based on distinct marker expression profiles. CD27, CD28, and CD117 are recommended as potential immunomarkers for flow cytometric analysis in POEMS syndrome.

The dihydrorhodamine-123 flow cytometry (DHR FC) assay is used to diagnose chronic granulomatous disease (CGD). This study presents the experience of a single center with the DHR FC assay in a large cohort to evaluate its applications and limitations. A total of 179 subjects were included in the study for CGD diagnosis, X-linked CGD (X-CGD) carrier determination, and post-hematopoietic stem cell transplantation (HSCT) chimerism monitoring. We performed the DHR FC assay using a standardized protocol, with additional intracellular myeloperoxidase (MPO) staining for borderline cases. The DHR FC assay demonstrated high diagnostic accuracy. PMA stimulation detected 94% of CGD cases. E. coli stimulation identified all CGD cases, including atypical EROS-deficient (CYBC1) patients (4.3% of the cohort) who exhibited residual reactive oxygen species production (median SI PMA = 40 vs. E. coli = 24). Genetic confirmation revealed that 82% of CGD patients had X-CGD (CYBB), and 18% had autosomal recessive CGD (CYBA/NCF1/NCF2/CYBC1) forms. Borderline results were clarified by MPO staining, which diagnosed three MPO-deficient cases. The assay reliably identified 43 X-CGD carriers out of 45 suspected cases and showed a strong correlation with the real-time quantitative polymerase chain reaction for HSCT chimerism monitoring (r = 0.78, p < 0.0001). The DHR FC assay is a rapid and reliable diagnostic tool for CGD, providing results within hours. Its applications extend to X-CGD carrier detection and post-HSCT chimerism monitoring. Dual-stimulant protocols (PMA + E. coli) and MPO staining enhance diagnostic accuracy. These findings support the use of the DHR FC assay as a versatile and essential tool in CGD management.

NPM1 mutations are among the most frequent genetic alterations in acute myeloid leukemia (AML) and have been associated with several immunophenotypic features. This study aims to characterize the immunophenotypic profile of this entity at diagnosis using multiparametric flow cytometry and to evaluate the impact of phenotype classifications on prognosis. Immunophenotypic analysis enabled the identification and characterization of various populations previously described in this entity, including immature (CD117⁺ HLA-DR⁺), neutrophil-committed (CD117^{+/heterogeneous} HLA-DR^-), and monocytic (with variable CD117 expression, HLA-DR⁺, and CD64⁺) leukemic cells, which were identified as leukemic expansions, as well as populations presenting immunophenotypic alterations. Cases were distributed in seven immunophenotypic patterns based on R-classification that considers the presence of the three previously described leukemic cell populations but independently of their proportion and relative distribution. Most of the patients included in this study (30, 33%) exhibited an immature and monocytic leukemic cells population (pattern 4), followed by those patients (16, 18%) with a predominant expansion of immature leukemic cells (pattern 1), and those (16, 18%) characterized by a neutrophil-committed leukemic population (pattern 2). Less frequent patterns included (11, 12%) neutrophil-committed and monocytic cells population (pattern 6), (7, 8%) coexistence of the three populations (pattern 7), (6, 7%) immature and neutrophil-committed leukemic cells population (pattern 5), and (5, 5%) predominant expansion of monocytic leukemic cells population (pattern 3). Our analysis indicated that cases with monocytic leukemic cells population predominance exhibit a trend towards a lower cumulative incidence of relapse compared to other leukemic populations, either as the predominant population or across different immunophenotypic patterns. However, differences did not reach statistical significance. These findings help us to contribute with additional information about the biological and immunophenotypic signature of NPM1-AML.

The objective of this 12-color/13-antibody single-tube panel is to assist in the diagnosis of T/NK-cell leukemias and lymphomas. In the clinical setting, the absence of a standardized T/NK-cell panel limits inter-laboratory data comparability, contributes to diagnostic variability, and results in redundant efforts across laboratories to design and validate panels for flow cytometry. Developing and promoting a panel that allows for rapid and fairly comprehensive labeling of surface T/NK-cell markers, including the anti-T-cell receptor β-chain constant region 1 (TRBC1) antibody, will streamline the workflow by establishing a standard immunophenotyping T/NK-cell panel for detecting neoplastic T/NK cells and lay the foundation for future COMIPs.

Quantifying malarial parasite density is crucial for diagnosis and treatment in endemic areas. While Malaria-derived particles (MDPs) have been linked to malaria pathology, a direct quantification method for routine laboratory use remains unestablished. To address this, our study optimized a flow cytometry approach to enumerate MDPs per microliter of blood. Specimens were incubated with propidium iodide and red blood cell (RBC) lysis solution. The number of MDPs was quantified using a CytoFlex flow cytometer, size-standard beads, and counting beads. Electron microscopy was used to study the ultrastructures of the malarial parasites in the lysed RBC specimens. A significant increase in MDP levels was detected in blood samples from P. falciparum and P. vivax infections, but fewer than 1 particle/μL of MDPs were detected in the controls. The number of MDPs correlated with the percentage of infected red blood cells (iRBCs) obtained by manual counting (R² = 0.94). The dilution assay demonstrated a strong correlation between the measured and expected values of the MDPs. An electron microscopic study demonstrated that different stages of malarial parasites exist in lysed RBCs in the form of membrane-bound spherical cells. A positive association was established between parasite density and MDPs across both P. falciparum (R² = 0.94) and P. vivax (R² = 0.91) infections. We demonstrated the potential use of flow cytometry for determining the MDP concentration. The developed approach is reliable and straightforward for the diagnosis and treatment of patients with malarial parasite infection in routine laboratory settings.