👤 Alessandro Laganà

Clonal mature B-cell lymphoproliferative disorders (B-LPDs) are a heterogeneous group of neoplasia characterized by the proliferation of mature B lymphocytes in the peripheral blood, bone marrow and/or lymphoid tissues. B-LPDs classification into different subtypes and their diagnosis is based on a multiparametric approach. However, accurate diagnosis may be challenging, especially in cases of ambiguous interpretation. Multiparameter flow cytometry (MFC) represents an extensively used technique to detect the presence of different cellular lines in immunology and hematology. MFC results provide an essential contribution to the B-LPDs diagnostic process, even more so considering that panels are constantly integrating novel markers to improve diagnostic accuracy. The aim was to evaluate the contributing role of MFC routinary studies by analyzing the expression and the mean fluorescence intensity (MFI) of CD200, ROR1, and CD43 in various B-LPDs to evaluate their usefulness in the differential diagnosis of these diseases. We retrospectively evaluated 2615 consecutive cases of newly collected samples (mostly from patients with lymphocytosis) analyzed by MFC carried out in the B-LPD diagnostic process referred to the Division of Hematology of the Sapienza University of Rome. We compared the results of CD200, ROR1, and CD43 expression percentage and their MFI between different subtypes of B-LPDs. In chronic lymphocytic leukemia (CLL), CD200, ROR1, and CD43 were always expressed with bright intensity. CLL samples presented high CD200 expression and MFI [CD200%, mean: 100 (range, 24-100); positivity rate: 100%; MFI, median = 125 (range, 10-1200)] statistically higher than mantle cell lymphoma (MCL) (p<0.001), which is usually negative for CD200, and variant hairy cell leukemia (vHCL, according to 2022 ICC) (p<0.001), but comparable with classic HCL (cHCL) (p>0.9). ROR1 resulted expressed in all CLL [ROR1%, mean: 100 (range, 52-100), positivity rate: 100%; MFI, median=50 (range, 10-202)] and MCL cases with comparable MFI (p>0.9). CD43 expression and MFI were significantly higher in CLL [CD43%, mean 99 (range, 59-100); positivity rate: 100%; MFI, median = 130 (range, 41-980)] than in MCL, vHCL, cHCL, and all the others mature B-cell neoplasia (p<0.001). CD200 and CD43 expression and MFI were significantly higher in cHCL compared to vHCL. Among the other mature B-cell neoplasia, CD200 was variably expressed in follicular lymphoma (FL), marginal zone lymphoma (MZL), diffuse large B-cell lymphoma (DLBCL), and lymphoplasmacytic lymphoma (LPL). ROR1 and CD43 presented a very low expression percentage in this latter group, being mostly negative. Persistent polyclonal B-cell lymphocytosis (PPBL) resulted in uniformly positive for CD200 and negative for ROR1 and CD43. Our data suggest that evaluating CD200, ROR1, and CD43 antigens and their intensity of expression, along with commonly used markers in MFC routine panels for B-LPDs, might be extremely useful for prompt diagnostic evaluation in the differential diagnosis of these diseases. Show less

Several genetic variants playing a key role in cholesterol levels, blood pressure, and vascular dysfunction influence the risk of Alzheimer's disease (AD) and vascular dementia (VaD). The many meta-analysis studies carried out on large numbers of samples in different populations have not provided clear results to date, because a trans-ethnic shift of risk genotypes in different populations is often observed. To determine genotypes allele frequencies of the polymorphisms most frequently identified to be correlated with cardio-cerebrovascular disease and AD in a Southern Italy population and to investigate their possible association with dementia. The genotype and allele frequencies of 13 cardio-cerebrovascular risk polymorphisms were assessed and their possible association with dementia was investigated in a case-control study, including 221 consecutive unrelated subjects diagnosed with dementia (120 subjects affected by AD, 55 by frontotemporal dementia, and 33 by vascular dementia) and 218 matched controls of Calabrian origin. Carriers of at least one APOEɛ4 allele resulted to be at higher risk of AD [OR(95% CI) = 2.721(1.477-5.011)] and VaD [OR(95% CI) = 6.205(2.356-16.342)] compared to non-carriers. Individuals with the IV genotype of the CETP polymorphism were more likely to have AD [OR(95% CI) = 2.427(1.364-4.319)] and VaD [OR(95% CI) = 3.649(1.455-9.152)] compared to subjects with the II-VV genotypes. CETP I405V polymorphism is likely a risk factor for AD and VaD in our cohort, independent of APOEɛ4 status. Unmodifiable genetic risk factors should be taken into account to promote a healthy lifestyle to prevent dementia. Show less