Ocrelizumab in Patients with Active Primary Progressive Multiple Sclerosis: Clinical Outcomes and Immune Markers of Treatment Response.

Ocrelizumab is a B-cell-depleting monoclonal antibody approved for the treatment of relapsing-remitting multiple sclerosis (RRMS) and active primary progressive MS (aPPMS). This prospective, uncontrolled, open-label, observational study aimed to assess the efficacy of ocrelizumab in patients with aPPMS and to dissect the clinical, radiological and laboratory attributes of treatment response. In total, 22 patients with aPPMS followed for 24 months were included. The primary efficacy outcome was the proportion of patients with optimal response at 24 months, defined as patients free of relapses, free of confirmed disability accumulation (CDA) and free of T1 Gd-enhancing lesions and new/enlarging T2 lesions on the brain and cervical MRI. In total, 14 (63.6%) patients and 13 patients (59.1%) were classified as responders at 12 and 24 months, respectively. Time exhibited a significant effect on mean absolute and normalized gray matter cerebellar volume (F = 4.342, p = 0.23 and F = 4.279, p = 0.024, respectively). Responders at 24 months exhibited reduced peripheral blood ((%) of CD19+ cells) plasmablasts compared to non-responders at the 6-month point estimate (7.69 ± 4.4 vs. 22.66 ± 7.19, respectively, p = 0.043). Response to ocrelizumab was linked to lower total and gray matter cerebellar volume loss over time. Reduced plasmablast depletion was linked for the first time to sub-optimal response to ocrelizumab in aPPMS.

Reduced expression of L-selectin in T-cells correlates with relative lymphocyte increase in patients with RRMS treated with natalizumab - functional implication towards PML risk.

Objectives: Natalizumab (NTZ), a treatment indicated for patients with highly active Relapsing - Remitting Multiple Sclerosis (RRMS), is known to induce increased relative frequency of lymphocytes. Progressive Multifocal Leukoencephalitis (PML) is a rare but serious adverse event related to NTZ. Moreover, reduced L-selectin (CD62L) expression in T-cells in cryopreserved samples of patients with RRMS under NTZ has been proposed as a biomarker of pre-PML state. We explore the association between L-selectin expression in T-cells and hematological parameters in freshly processed samples of patients with RRMS under NTZ.Methods: We studied L-selectin expression in patients with: RRMS under NTZ (n=34), fingolimod (FTY, n=14), interferon-beta (IFNß, n=22), glatiramer acetate (GA, N=17); in 9 patients with secondary progressive (SP) MS and in 6 healthy controls. Twenty-two patients under NTZ and 6 patients under FTY were followed for 18 months. One NTZ-treated patient developed PML during the study.Results: Patients under NTZ exhibited increased relative frequency of lymphocytes (40.02±1.45) compared to patients under first-line treatment (30.57±1.68, p<0.001) and to patients with SPMS (29±1.56, p=0.02), and a lower mean L-selectin expression in (69.39±1.73) compared to patients under first-line treatment (79.1±1.17, p=0.003). A negative correlation between the relative frequency of CD4+CD62L+ T-cells and the absolute lymphocyte counts (Pearson's r=0.367, p=0.033) was observed.Discussion: We hereby provide mechanistic insight in a possible pathway implicated in NTZ-related PML risk. These results further underline the need for thorough validation of L-selectin expression in T-cells as a potential pre-PML biomarker.

Evaluation of a 10color protocol as part of a 2tube screening panel for flow cytometric assessment of peripheral blood leukocytic subsets.

Peripheral blood (PB) immunophenotyping is commonly required for initial evaluation of various suspected disease entities. Several approaches have been proposed. The objective of this work is to explore the value of a 10color protocol developed in our laboratory for flow cytometric assessment of PB leukocytic subsets, as part of a 2tube screening panel. A combination of CD16/CD56/CD34/CD33/CD19/CD4/CD8/CD3/CD20/CD45 antibodies in 1 tube was applied routinely during flow cytometric analysis of PB samples for diagnostic purposes. The protocol was systematically complemented by a 2nd tube with anti-kappa, anti-lambda, CD5, CD19, and CD45 antibodies for adults and selected pediatric patients, and specifically oriented panels when necessary. 25 samples with no detectable neoplastic PB involvement and 31 samples with a hematolymphoid disorder were investigated retrospectively. The contribution of CD33 in the separation of leukocytic populations, as well as the benefits from the simultaneous assessment of CD20/CD19/CD45, CD16/CD56 and the detection of CD34+ cells were examined. The gating strategy with the use of CD33 provided additional information in certain cases. The protocol enabled recognition of differential expression of CD20 and CD45 in CD19+ cells with chronic lymphocytic leukemia phenotype, overall evaluation of NK and NK like T cells, estimation of CD16- granulocytes and CD56/CD16 expression in monocytes, as well as identification of minor cell subsets, such as CD34+ cells. The proposed 10color combination of antibodies analyzed in a standardized manner can offer significant information in the initial evaluation of PB samples, thus, guiding subsequent investigation if needed.

CD5+ B lymphoproliferative disorder with subsequent development of plasma cell leukaemia: Diagnostic and aetiologic reasoning.

BACKGROUND: Plasma cell myeloma (PCM) has been sporadically reported to occur simultaneously or subsequently to mature B lymphoproliferative disorders (LPDs), predominantly chronic lymphocytic leukaemia (CLL). METHODS: We describe the clinical and laboratory findings of a 69-year-old male patient who developed plasma cell leukaemia (PCL) 8 years after an initial diagnosis of a low stage CD5+ B LPD and 3 years after treatment for LPD. RESULTS: The transition from a clinically indolent B LPD to an aggressive PCM was documented by bone marrow (BM) biopsy, while flow cytometric (FC) immunophenotyping conferred additional information by disclosing the co-existence of both disorders in BM and the presence of abnormal monotypic PCs in peripheral blood above PCL levels. Phenotypic findings suggested a discrete clonal origin of the two disorders. CONCLUSIONS: This report of PCL development in a patient with residual CD5+ B LPD, emphasizes the need for comprehensive diagnostic evaluation of such cases and scrutiny of their aetiological relationship, including FC immunophenotyping due to its high analytical sensitivity and multiparametric capacity compared to morphology or immunohistochemistry alone. © 2017 International Clinical Cytometry Society.

Utility of hematology analyzer and flow cytometry in timely and correct detection of circulating plasma cells: Report of three cases.

BACKGROUND: Circulating neoplastic plasma cells (PCs) are a common feature between classical plasma cell myeloma (PCM) and its aggressive variant, plasma cell leukemia (PCL), with their early suspicion and detection being of clinical importance for prognostic and diagnostic purposes. METHODS: Morphological and flow cytometric enumeration and characterization of peripheral blood (PB) neoplastic PCs were performed in 3 PCM patients after complete blood count (CBC) evaluation. RESULTS: Early suspicion of circulating PCs by initial CBC scatter plots and monocytosis led to morphological enumeration of PCs, with low level of concordance between morphologists. Flow cytometric PB analysis permitted accurate quantification and characterization of circulating clonal PCs. CONCLUSIONS: CBC findings can prompt early suspicion of circulating PCs in PCM patients leading to early and accurate flow cytometric analysis of clonal PCs in addition to morphological PB evaluation. The suggested combined approach proved to be most important in the PCL case with discordant morphological evaluations and marginal PC numbers according to current criteria. © 2016 International Clinical Cytometry Society.

C-reactive protein/interleukin-6 ratio as marker of the size of the uncomplicated thoracic aortic aneurysms.

OBJECTIVES: The role of C-reactive protein (CRP) and interleukin-6 (IL-6) as markers in the prognosis of asymptomatic thoracic aortic aneurysm (TAA) patients has not been well established. As such, we evaluated a group of patients for a possible association between serum CRP and IL-6 and aneurysm dimension. METHODS: Serum CRP and IL-6 were determined and aneurysmal size was measured in 26 patients with TAA. RESULTS: The mean (SD) CRP and IL-6 were 0.58 (1.07) and 7.47 (17.78) pg/ml, respectively. Serum CRP, IL-6 and the ratio CRP/IL-6 correlated with the descending aortic aneurysmal dimension (r = 0.426, r = 0.743 and r = 0.328, respectively). A significant correlation was also found between values of the ratio above 0.8 and aneurysmal dimension (both ascending and descending aneurysms) (r = 0.785). Additionally, a significant association between smoking, age group above 69 years and dyslipidemia and aneurysm dimension was established (P = 0.002, P = 0.061 and P = 0.070, respectively). CONCLUSIONS: This report shows that serum CRP, IL-6 levels and the ratio CRP/IL-6 are associated with descending aortic aneurysmal dimensions. Also values of the ratio CRP/IL-6 above 0.8 are associated with aneurysmal dimensions for both ascending and descending aortic aneurysms. It is still early to establish the clinical significance of those findings, and further studies with larger groups of patients with longer follow-up are required in order to truly assess the usefulness of the serum CRP and IL-6 as markers in relation to the progression of the disease.

Detection of CD55- and CD59-deficient granulocytic populations in patients with myelodysplastic syndrome.

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by absence of CD55 and CD59 from the surface of affected cells. PNH has been associated with myelodysplastic syndromes (MDS). The aim of our study was to estimate the prevalence of the PNH clone in MDS patients by detecting CD55 and CD59 deficiency. We studied 90 MDS patients: 19 patients with RA, 15 with refractory anemia with ringed sideroblasts (RARS), 18 with refractory anemia with excess of blasts (RAEB), 17 with refractory anemia with excess of blasts in transformation (RAEB-t), and 21 with chronic myelomonocytic leukemia (CMML). Twenty healthy individuals were also studied as the control group. We studied the PNH clone on granulocytes of these patients with the aid of flow cytometry. CD55- and CD59-deficient granulocytic populations were detected in 15.5% of MDS patients compared to 2.8% of normal individuals. Among the subgroups of the study, significant difference was present in three cases: (1) between CMML and control, (2) between CMML and RA, and (3) between CMML and RARS. These data indicate a possible association between PNH phenotype and MDS. MDS patients of worse prognosis (CMML) express more strongly the PNH clone compared to those of better prognosis (RA and RARS). Perhaps, the examination of MDS patients for the PNH clone by flow cytometry could provide us with a valuable prognostic tool.