Hematopoiesis and immune reconstitution after CD19 directed chimeric antigen receptor T-cells (CAR-T): A comprehensive review on incidence, risk factors and current management.

Impaired function of hematopoiesis after treatment with chimeric antigen T-cells (CAR-T) is a frequent finding and can interest a wide range of patients, regardless of age and underlying disease. Trilinear cytopenias, as well as hypogammaglobulinemia, B-cell aplasia, and T-cell impairment, can severely affect the infectious risk of CAR-T recipients, as well as their quality of life. In this review, we provide an overview of defects in hematopoiesis after CAR-T, starting with a summary of different definitions and thresholds. We then move to summarize the main pathogenetic mechanisms of cytopenias, and we offer insight into cytomorphological aspects, the role of clonal hematopoiesis, and the risk of secondary myeloid malignancies. Subsequently, we expose the major findings and reports on T-cell and B-cell quantitative and functional impairment after CAR-T. Finally, we provide an overview of current recommendations and leading experiences regarding the management of cytopenias and defective B- and T-cell function.

Coronavirus disease 2019 (COVID-19): Focus on peripheral blood cell morphology.

Numerous studies have shown peculiar morphological anomalies in COVID-19 patients' smears. We searched all the peer-reviewed scientific publications that explicitly reference the cytomorphological alterations on peripheral blood smears of patients with COVID-19. We extracted data from sixty-five publications (case reports, patient group studies, reviews, and erythrocyte morphology studies). The results show that frequent alterations concern the morphology of lymphocytes (large lymphocytes with weakly basophilic cytoplasm, plasmacytoid lymphocytes, large granular lymphocytes). Neutrophils display abnormal nuclei and cytoplasm in a distinctive cytomorphological picture. Besides a left shift in maturation, granulations can be increased (toxic type) or decreased with areas of basophilia. Nuclei are often hyposegmented (pseudo-Pelger-Huёt anomaly). Apoptotic or pycnotic cells are not uncommon. Monocytes typically have a large cytoplasm loaded with heterogeneous and coalescing vacuoles. Platelets show large and giant shapes. The presence of erythrocyte fragments and schistocytes is especially evident in the forms of COVID-19 that are associated with thrombotic microangiopathies. Such atypia of blood cells reflects the generalized activation in severe COVID-19, which has been demonstrated with immunophenotypic, molecular, genetic, and functional methods. Neutrophils, in particular, are involved in the pathophysiology of hyperinflammation with cytokine storm, which characterizes the most unfavorable evolution.

Successful "on-demand" plerixafor for autologous peripheral blood stem-cells transplantation for relapsed/refractory germ cell tumors.

BACKGROUND: Germ cell tumors represent, among solid cancers, a potentially curable disease even if up to 20% to 30% of patients (pts) relapse after first-line treatment especially considering intermediate and poor prognosis groups. In this scenario, patients are candidates for high-dose chemotherapy and autologous stem-cells transplantation as second-line treatment even though stem-cells mobilization potential can be affected by several cycles and regimens of chemotherapy. To date, plerixafor is authorized in poor mobilizer adult pts diagnosed with lymphoma or multiple myeloma and in pediatric solid tumors or lymphoma. Therefore, the use of plerixafor in adult pts with relapsing/refractory GCT is still off label. MATERIALS AND METHODS: In our study, we describe mobilization and collection of peripheral blood stem cells for 10 pts with germ cell tumors. Six patients underwent plerixafor administration since classified as poor mobilizers based on WBC count (>5.000/µL) and CD34+ cell count (<15/µL) the day before apheresis procedure. RESULTS: On the first day of apheresis, plerixafor administration in poor mobilizers made possible a remarkable boost of CD34+ cells in such a way to overlap that of good mobilizers' (32/µL vs 35/µL, respectively, P > .05). CONCLUSION: Therefore, in our experience, plerixafor made a good fraction of poor mobilizer patients eligible for mobilization and collection and able to undergo the predicted autologous stem-cells transplantation; thus, the lack of access to the use of plerixafor in this setting of patients risks jeopardizing an effective treatment, especially in case of poor prognosis.

Inline and offline extracorporeal photopheresis: Device performance, cell yields and clinical response.

BACKGROUND: Extracorporeal photopheresis (ECP) is an effective treatment for graft-vs-host-disease (GvHD). Photopheresis can be performed in offline or inline method. The first uses a conventional cell separator for collection of mononuclear-cells that are photoactivated by a separate device and manually reinfused; the second one involves a dedicated device performing the entire procedure (collection, photoactivation and reinfusion). STUDY DESIGN AND METHODS: The objective was to compare the two methods and cell product features to highlight key process, devices performance, and to evaluate ECP clinical response. Patients developing steroid-resistant GvHD underwent ECP as second-line treatment using either inline (Therakos CellEx) or offline system (Terumo BCT Spectra or Optia and UVA PIT system). Data about patients' features, pre-apheresis blood-count, cell product characteristics and clinical response were collected for analysis. RESULTS: We evaluated 494 procedures performed on 28 patients from April 2018 to March 2019. The offline procedure allows to achieve greater cell yield, it is characterized by larger processed blood volume, longer runtime, and higher ACD consumption. The inline procedure shows shorter runtime, high mononuclear-cells percentage and low percentage of granulocytes in cell product. We observed a significant difference in cell yields between inline and offline system; furthermore we did not find a significant relationship between cell dose and clinical response. CONCLUSION: Inline ECP is fast, highly automated and productive, making it particularly suitable for ECP treatments. Offline ECP collects high cell yields implying longer procedure and greater operator intervention. Our study did not find a significant relationship between cell dose and GVHD response.

The role of eosinophil morphology in distinguishing between reactive eosinophilia and eosinophilia as a feature of a myeloid neoplasm.

Morphological features of eosinophils in patients with reactive eosinophilia (28 patients) and clonal eosinophilia (26 patients) have been compared with each other and with the eosinophil characteristics of healthy volunteers (three subjects) and of patients with the idiopathic hypereosinophilic syndrome (three patients). Morphological features, assessed in isolation from other haematological abnormalities, were found to have poor specificity for a myeloid neoplasm. The most useful feature was the presence of basophilic granules in mature eosinophils, which was associated particularly with acute myeloid leukaemia with inv(16). Marked reduction in granules occurred more often in some subsets of the myeloid neoplasm group but nevertheless was lacking in specificity since it was not infrequently seen in reactive eosinophilia. Although experienced morphologists more often considered that a myeloid neoplasm was likely in patients in whom this was the diagnosis (69%), myeloid neoplasia was also considered likely in a considerable proportion (39%) of patients with reactive eosinophilia. Morphological abnormalities of eosinophils therefore cannot be assessed in isolation in seeking to make a diagnosis of a myeloid neoplasm. Morphology is, however, needed and should be integrated with the results of other investigations.

Peripheral Blood Hemopoietic Stem Cell Mobilization Regimens in POEMS Syndrome: A Retrospective Study at 2 Hematologic Italian Centers.

Autologous peripheral blood stem cell transplantation should be considered first-line therapy in young patients with POEMS. The best protocol to collect peripheral blood stem cells remains to be defined, because of the disease rarity and the heterogeneity of published case series. We collected clinical and laboratory data from 25 patients undergoing mobilization, of whom 11 were mobilized using cyclophosphamide (CY) followed by granulocyte colony-stimulating factor (G-CSF) and 14 patients using G-CSF. The incidence of poor mobilization was low and not statistically different between the 2 groups. Both schemes (CY plus G-CSF versus G-CSF alone) were able to harvest a sufficient CD34+ cell dose.

Inline extracorporeal photopheresis: evaluation of cell collection efficiency.

BACKGROUND: Extracorporeal photopheresis (ECP) therapy has proved to be an effective and safe treatment for graft-versus-host-disease (GvHD), an important complication after hematopoietic stem cell transplantation. In 2016, we acquired Therakos CellEx, a dedicated inline ECP device to accomplish a significant increase in ECP activity. In literature, we found few data reporting CellEx performance evaluated in terms of collection efficiency to qualify the device. Hence, we decided to collect and analyze our data in order to build a reference in terms of expected results of the procedure. Here we report our data of ECP performed using CellEx in a 12-month period focusing on collection efficiency assessment, as well as procedural and apheretic product characteristics. STUDY DESIGN AND METHODS: We collected data of patients undergoing ECP from April 2018 to March 2019 using CellEx in order to evaluate collection efficiency. RESULTS: Between April 2018 and March 2019 we treated 28 adult patients affected by GvHD performing 319 ECP using CellEx. CellEx mononuclear cell product was characterized by high mononuclear cell percentage and low percentage of granulocytes, resulting particularly suitable for ECP treatments. Median collection efficiency for total nucleated cells and for mononuclear cells was 31.2% and 62.3%, respectively. CONCLUSION: Collection efficiency of CellEx was comparable to that usually obtained by cell separators designed for cell collection and was comparable to that of offline systems. Our results provide a detailed performance evaluation for inline ECP system users.

Dyserythropoiesis in the diagnosis of the myelodysplastic syndromes and other myeloid neoplasms: problem areas.

An evaluation of the significance of specified dyserythropoietic features in suspected myelodysplastic syndrome (MDS) and acute myeloid leukaemia with erythroid dysplasia was made by means of evaluation of 100 electronic images of bone marrow erythroblasts from each of 20 subjects: 11 with a myeloid neoplasm, six with another condition that could cause erythroid dysplasia and three healthy controls. The evaluation was carried out independently by seven experienced haematologists/haematopathologists who were blinded to the diagnosis. The majority of the dyserythropoietic features listed in the World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissues were validated, although karyorrhexis was found to be infrequent and lacking in specificity; multinuclearity and megaloblastosis were more often observed but also lacked specificity. Good majority agreement on the identification of dysplastic features was obtained. Despite this, it was demonstrated that a reliable diagnosis of MDS can often not be made on the basis of erythroid morphology alone. Interpretation of dyserythropoiesis must be carried out with full knowledge of other clinicopathological features and with a constant awareness of the other conditions that can be confused with MDS. An iron stain is essential, as cases with ring sideroblasts may otherwise not be recognised as having MDS.

Emergency response of four transfusion centers during the last Chikungunya outbreak in Italy.

Between September 15 and November 11, 2017, the area of Rome was subjected to cessation of donation in an area of approximately 1,300,000 inhabitants and with a 5-day quarantine for the rest of metropolitan areas due to Chikungunya virus (CHIKV) outbreak. Quarantine was applied to red blood cell (RBC) and plasma units while platelet concentrates (PCs) were subjected to pathogen inactivation methods (PIMs). Quarantine was based on an active recall of all donors and, in case of declared absence of any symptom or illness, on release of RBC and plasma units after 5 days. Four regional centers in which PIMs were already performed were charged for PIMs for the rest of Rome's area. These centers increased by 236% their previous PIM procedures, producing additional 1425 pathogen-reduced (PR) PCs in 57 days, beside their production (996 PR PCs) for local needs. The emergency support was close to the maximal production capacity of the four centers and was successful only thanks to the limited length of emergency. No adverse events were reported by all centers through a passive hemovigilance approach and by a follow-up of approximately 4 months. None of the donors referred symptoms or illness at recall and none of the blood products were discarded after quarantine. To date, no cases of CHIKV-transmitted infection were reported in transfused patients. This experience has taught some relevant strategic and organizing aspects that should be taken into account when an infectious outbreak must be faced in a large metropolitan area.

Mononuclear cell collection for extracorporeal photopheresis: Concentrate characteristics for off-line UV-A irradiation procedure.

BACKGROUND AND OBJECTIVE: Extracorporeal photopheresis (ECP) is the most represented cell therapy for treatment of cutaneous T-cell lymphoma, graft-versus host disease and organ rejection. We analyzed our experience in ECP using 2 cell separators (Cobe Spectra and Spectra Optia) focusing on leukapheretic product characteristics, UV-A irradiation procedure and entire ECP process. MATERIALS AND METHODS: We collected data of patients undergoing ECP between January 2012 and February 2015 in order to evaluate collection procedures performed using Cobe Spectra and Spectra Optia, mononuclear cell product, UV-A photoirradiation procedure by Pit System. RESULTS: We performed 484 ECP procedures in 27 patients. Cobe-derived mononuclear cell products were characterized by higher cell yields while Optia-derived mononuclear cell products were characterized by smaller volume, comparable mononuclear cell content but lower erythrocytes, granulocytes, and platelets contamination. CONCLUSION: Our study confirms good results for both cell separators. Blood volume processed being equal, Cobe collects a number of total nucleated cells significantly higher than Optia. Optia, collecting only target cells without significant erythrocytes, granulocytes and platelets contamination, is able to collect a leukapheretic product particularly suitable for ECP.

Red Cell Alloantibody Screening: Comparative Analysis of Three Different Technologies.

BACKGROUND: The detection of irregular antibody is a critical issue in the management of red blood cell transfusion according to the Type & Screen (T&S) practice. In order to implement the T&S procedure at our blood bank, we compared three different automated analyzers based on column agglutination technique (CAT) or solid phase red cell adherence assay (SPACA) methods. METHODS: Pre-transfusion antibody screening was performed in 986 patients candidate to elective surgery at low risk for red blood cell transfusion. We tested the following kits: the three-cell panel micro-CAT system ID-DiaCell I-II-III (DiaMed), the four-cell panel solid-phase system Capture-R Ready Screen-4 (Immucor), and the four-cell panel micro-CAT system Serascan Diana-4 (Grifols). Positive results were further investigated using corresponding identification panels, and discrepant results were investigated with all the antibody identification systems. RESULTS: Among 986 samples, we observed 967 concordant negative results (98.1%), 8 concordant positive results (0.8% of cases), and 11 discrepant results (1.1%). Among discrepant samples, an alloantibody could been identified in two patents (anti-M, detected by Serascan Diana-4 and ID-DiaCell I, II, III; anti-Kpa, detected by Capture-R Ready Screen-4 and Serascan Diana-4). CONCLUSION: Among the evaluated technologies, the four-cell panel micro-CAT system displayed the highest sensitivity and specificity with an optimal negative predictive value. These features might be relevant to the routine implementation of the T&S transfusion strategy.

Cytomorphology review of 100 newly diagnosed lower-risk MDS patients in the European LeukemiaNet MDS (EUMDS) registry reveals a high inter-observer concordance.

The European LeukemiaNet MDS (EUMDS) registry is collecting data of myelodysplastic syndrome (MDS) patients belonging to the IPSS low or intermediate-1 category, newly diagnosed by local cytologists. The diagnosis of MDS can be challenging, and some data report inter-observer variability with regard to the assessment of the MDS subtype. In order to ensure that correct diagnoses were made by the participating centres, blood and bone marrow slides of 10% of the first 1000 patients were reviewed by an 11-person panel of cytomorphologists. All slides were rated by at least 3 panel members (median 8 panel members; range 3-9). Marrow slides from 98 out of 105 patients were of good quality and therefore could be rated properly according to the WHO 2001 classification, including assessment of dysplastic lineages. The agreement between the reviewers whether the diagnosis was MDS or non-MDS was strong with an intra-class correlation coefficient (ICC) of 0.85. Six cases were detected not to fit the entry criteria of the registry, because they were diagnosed uniformly as CMML or AML by the panel members. The agreement by WHO 2001 classification was strong as well (ICC = 0.83). The concordance of the assessment of dysplastic lineages was substantial for megakaryopoiesis and myelopoiesis and moderate for erythropoiesis. Our data show that in general, the inter-observer agreement was high and a very low percentage of misdiagnosed cases had been entered into the EUMDS registry. Further studies including histomorphology are warranted.

The role of molecular typing and perfect match transfusion in sickle cell disease and thalassaemia: An innovative transfusion strategy.

Chronic red blood cell transfusions remain an essential part of supportive treatment in patients with thalassaemia and sickle cell disease (SCD). Red blood cell (RBC) transfusions expose patients to the risk of developing antibodies: RBC alloimmunization occurs when the immune system meets foreign antigens. We created a register of extensively genotyped donors to achieve a better matched transfusion in order to reduce transfusion alloimmunization. Extended RBC antigen typing was determined and confirmed by molecular biology techniques using Human Erythrocyte Antigen (HEA) BeadChip (BioArray Solutions Ltd., Warren, NJ) in periodic blood donors and in patients with thalassaemia and SCD. During 3 years, we typed extensively 1220 periodic blood donors, 898 male and 322 female. We also studied 10 hematologic patients affected by thalassaemia and sickle cell disease referred to our institution as candidate to periodic transfusions. Our patients (8 females and 2 males with a median age of 48 years, range 24-76 years), extensively typed using molecular techniques and screened for RBC alloantibodies, were transfused with a median of 33.5 RBC units. After three years of molecular typing, the "perfect match" transfusion strategy avoided new alloantibodies development in all studied patients.

Real-life use of erythropoiesis-stimulating agents in myelodysplastic syndromes: a "Gruppo Romano Mielodisplasie (GROM)" multicenter study.

The Gruppo Romano Mielodisplasie (GROM) conducted a retrospective study in 543 patients with myelodysplastic syndromes (MDS) to evaluate the safety and efficacy of erythropoiesis-stimulating agents (ESAs) in "real-life" clinical practice. The 40.000-UI/week erythropoietin (EPO)-alpha and 30.000-UI/week EPO-beta starting dose were defined "standard," and 80,000 UI/week EPO-alpha and 60.000 UI/week EPO-beta were defined "high." Response was defined according to International Working Group (IWG) 2006 criteria. At ESA's start, median age was 74.2 years (interquartile range (IR) 67.8-79.5) and median hemoglobin was 8.9 g/dl (IR 8.2-9.6). Median time from diagnosis to ESAs start was 3.8 months (IR 0.8-13.2). ESA starting dose was "standard" in 361 patients (66.5 %) and "high" in 182 patients (33.5 %). Erythroid response was observed in 82/185 (44.3 %) transfusion dependent (TD) patients as compared with 226/329 (68.6 %) transfusion independent (TI) ones (p < 0.001). At multivariate analysis, in TD patients, only endogenous EPO levels <50 mU/l were significant (p = 0.046), whereas in TI patients, high-dose ESAs (p < 0.001), abnormal creatinine levels (0.009), and endogenous EPO levels <50 mU/l (p = 0.014) were predictors of response. Responders showed a higher 5-year overall survival (OS) (57.8 vs. 32.2 %, p < 0.001) and leukemia-free survival (76.0 vs. 49.8 %, p < 0.001). At multivariable analysis for OS, response to ESA, low International Prognostic Scoring System (IPSS), no transfusion need, and female sex showed an independent favorable prognostic role. Our results confirm that treatment with ESAs is effective in a real-life MDS setting, particularly at high dose and in TI patients. Prospective studies are needed to define the optimal starting dose.

Standard dose and prolonged administration of azacitidine are associated with improved efficacy in a real-world group of patients with myelodysplastic syndrome or low blast count acute myeloid leukemia.

OBJECTIVE: Azacitidine is the standard of care for higher-risk myelodysplastic syndromes (MDS). We evaluated factors affecting the outcome of azacitidine treatment in 196 'real-world' patients, retrospectively collected by two Italian cooperative groups. METHODS: The study included 184 MDS and 12 low blast count acute myeloid leukemia (AML). Azacitidine was administered at the standard dose of 75 mg/m(2)/d for 7 d (SD) in 163 patients and 100 mg/d for 5-7 d in 33 patients. RESULTS: After a median of 4.5 azacitidine cycles (range 7-15 cycles), 182 patients were evaluable for response. Nineteen percent achieved complete remission (CR), 17% partial remission (PR), and 21% hematological improvement (HI). The disease was stable or progressive in 29% and 14% of patients, respectively. The probability of response was significantly higher in patients who received the 75 mg/m(2)/7 d compared with 100 mg through 5-7 d dose (CR/PR/HI: 63 vs. 29%, P = 0.0005). Median overall survival was 17.1 months. Low MDS-CI and achievement of CR/PR/HI were significant predictors of survival in the multivariable analysis. CONCLUSIONS: Our data show that maximal azacitidine efficacy is associated with the standard dose and with prolonged treatment, beyond 4-6 cycles, with the goal of also improving the 'quality' of response. Lower MDS-CI and IPSS-R scores, hematologic response and disease stability, are associated with longer survival. The risk of febrile events is highest during the first treatment cycles and is associated with active disease.