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Most hematopoietic stem cell transplants performed for an autoimmune disease of the nervous system, use the patient's hematopoietic stem cells (HSCs). Obtaining an HSC graft is the first step of the process. This typically involves mobilization of bone marrow HSCs into the circulation using high-dose cyclophosphamide followed by filgrastim, a drug based on granulocyte colony-stimulating factor. Toxicity from these agents is usually manageable and adverse events are less severe and less frequent than those experienced during the hematopoietic stem cell transplant. Following mobilization, HSCs are collected from the circulation by leukapheresis. Some centers deplete the graft of lymphocytes using an ex vivo immunomagnetic selection procedure. HSC grafts are cryopreserved until required for the stem cell transplant. Quality testing of the graft ensures sterility and it contains sufficient HSCs and hematopoietic progenitors. The clinical and laboratory aspects of HSC graft mobilization, collection, and storage must meet standards set by national regulatory bodies and accredited by international professional standards organizations. Experienced stem cell transplant teams are important for minimizing procedural toxicity and enhancing successful collection.

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INTRODUCTION: Effective mobilization of Stem Cells(SCs) to peripheral blood (PB) is crucial for obtaining sufficient CD34+ cell numbers via apheresis. The ratio of pre-apheresis PB CD34+ cells is the best parameter for predicting the product CD34+ cell count. However, quantitating CD34+ PB cells requires flow cytometry, which usually takes two or more hours to obtain the results. We hypothesized that the product CD34+ cell count could be predicted using the counts of white blood cells (WBCs), mononuclear cells (MNCs), and pre-apheresis CD34+ cells. A formula that achieves this would substantially affect the efficiency and effectiveness of apheresis. We, therefore, aimed to estimate the number of CD34+ cells in the product using a formula that incorporates pre-apheresis PB WBC, MNC, and CD34+ cell counts and product WBC and MNC counts. METHODS: We examined the results of 373 leukapheresis procedures for SC mobilization. Effective separation of CD34+ PBSCs (count/µL) via apheresis was estimated using the following formula: [Product WBC (count/µL) × MNC (count/µL) × pre-apheresis CD34+ cell (percentage/µL)] ÷ [PB WBC count/µL × PB MNC (count/µL)]. RESULTS: A strong correlation was observed between the CD34+ cell count calculated using our formula and the post-apheresis CD34+ cell count measured via flow cytometry (R = 0.939, based on linear regression analysis). In the subgroup analysis, this correlation was observed for all the disease subgroups and healthy donors. CONCLUSION: We developed a formula that predicts the product CD34+ cell count and is useful for determining whether a second apheresis procedure will be required.

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In the frontline high-dose phase 3 FIL-MCL0208 trial (NCT02354313), 8% of enrolled mantle cell lymphoma (MCL) patients could not be randomised to receive lenalidomide (LEN) maintenance vs observation after autologous stem cell transplantation (ASCT) due to inadequate hematological recovery and 52% of those who started LEN, needed a dose reduction due to toxicity. We therefore focused on the role played by CD34 + hematopoietic stem cells (PBSC) harvesting and reinfusion on toxicity and outcome. Overall, 90% (n = 245) of enrolled patients who underwent the first leukapheresis collected ≥ 4 × 106 PBSC/kg, 2.6% (n = 7) mobilized < 4 × 106 PBSC/kg and 7.7% (n = 21) failed the collection. Similar results were obtained for the planned second leukapheresis, with only one patient failing both attempts. Median count of reinfused PBSC was 5 × 106/kg and median time to recovery from neutropenia G4 was 10 days from ASCT. No impact of mobilizing subtype or number of reinfused PBSC on hematological recovery and LEN dose reduction was noted. At a median follow-up of 75 months from ASCT, PFS and OS of transplanted patients were 50% and 73%, respectively. A long lasting G4 neutropenia after ASCT (> 10 days) was associated with a worse outcome, both in terms of PFS and OS. In conclusion, although the harvesting procedures proved feasible for younger MCL patients, long-lasting cytopenia following ASCT remains a significant issue: this can hinder the administration of effective maintenance therapies, potentially increasing the relapse rate and negatively affecting survival outcomes.

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INTRODUCTION: Granulocyte transfusion is one of the best therapeutic modalities in prolonged neutropenic patients with severe bacterial/fungal infections. Granulocyte harvest using conventional acid citrate dextrose (ACD) anticoagulant (ACD-A) by apheresis is not satisfactory in comparison to the use of hydroxyethyl starch (HES), but the latter is associated with various adverse events, especially with high-molecular-weight HES. AIMS AND OBJECTIVE: This study aimed to assess the beneficial impact of the use of medium-molecular-weight (MMW)-HES and trisodium citrate combination over ACD-A in granulocyte apheresis when using Spectra Optia. MATERIALS AND METHODS: This was a retrospective study comparing granulocyte harvest results with the use of ACD or HES and trisodium citrate combination. All the donors in both the groups received single 600 µg of granulocyte colony-stimulating factor subcutaneous injection followed by 8 mg of dexamethasone tablet 10-12 h and omnacortil 60 mg orally 3 h before harvest. A number of adverse incidents, if any, were observed and noted. Donor/procedure parameters were compared using Mann-Whitney U-test/unpaired t-test. RESULTS: Granulocyte yield (mean: 3.29 × 1010/unit vs. 4.5 × 1010/unit in the ACD and HES groups, respectively, P ≤ 0.0001) was significantly better in the HES group. The collection efficiency was also better in the HES group (mean: 15.86% vs. 26.70% in the ACD and HES groups, respectively, P ≤ 0.0001) in the ACD and HES groups, respectively. There was no significant adverse event noted in any of these two groups. CONCLUSION: In our study, granulocytes with optimum yield can be easily harvested with Spectra Optia cell separator using 6% HES (MMW) and trisodium citrate combination with standard 12-h interval gap between mobilization and harvest. This strategy can also have no or minimal extra cost burden to patients.

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Respiratory failure, intracranial hemorrhage and infection were more common in hyperleukocytic acute myeloid leukemia patients than in non-hyperleukocytic leukemia patients. Compared with non-apheresis treatment, the white blood cells decreased significantly and the infection rate decreased after apheresis treatment. However, the treatment time of leukapheresis in patients with hyperleukocytic leukemia is very long, while it is more damaging to cells. In this study, which conducted a retrospective analysis on patients with hyperleukocytic acute myeloid leukemia, the process of centrifugation of normal cells and patients' cells by apheresis machine was simulated in vitro. Through selecting 5 healthy persons and 11 patients with hyperleukocytic acute myeloid leukemia, extracting their blood samples and performing in vitro centrifugation at different speeds or duration, we observed the changes of the numbers and morphology of peripheral blood cells in healthy people and patients, so as to explore the optimal centrifugation parameters during leukapheresis. The cells obtained by the optimal centrifugation parameters were cryopreserved and two groups of mice (10 mice in each group) were used to establish leukemia animal models. Through the research, it is found that when the centrifugal speed is below 6000 rpm, the damage to blood cells in healthy people and in patients with hyperleukocytic leukemia is not obvious. When the centrifugal speed is above 6000 rpm, the platelets will be damaged significantly. The cells obtained under the optimal centrifugation parameters can be successfully cryopreserved and used to establish leukemia animal models. This study is of great significance for improving the efficiency and reducing the side effects of leukapheresis, and is helpful to improve the treatment of white blood cells reduction.

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Cytoreduction in leukostasis can be achieved using leukapheresis. We report a case of chronic myeloid leukemia (CML) identified by a persistent erection, which was successfully treated using the Spectra Optia®ï¸Ž apheresis system. A 29-year-old male presented with an erection for 12 hours without identified triggers and no improvement despite penile corpus cavernosum puncture. His white blood cell count was 458,930/µL. A diagnosis of CML-induced persistent erection with secondary hyperleukocytosis was established. Following an emergency bilateral penile corpus cavernosum incision (distal shunting), he received hydroxyurea and febuxostat. Persistent erection resolved after leukapheresis for two consecutive days. Rapid leukocyte count reduction can effectively address leukostasis in CML without major complications.

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INTRODUCTION: Peripheral blood stem cells (PBSC) mobilization with granulocyte colony stimulating factor (G-CSF) for healthy donors is generally performed at 5th day. However, earlier collection is sometimes feasible, raising the question of whether to initiate apheresis early to limit further G-CSF exposure, while considering the risk of mobilization failure. In the current study, we examined the factors predicting successful 4th day collection and developed a model that can be used practically. PATIENTS AND METHODS: The study was carried out by obtaining the data of PBSC mobilizations performed between January 2009 and September 2022 in our transplantation center. RESULTS: A total of 141 healthy donors with a median donor age of 32 (18-64) were included. Adequate mobilization was achieved in 115 (81.6 %) patients. Median peripheral CD34 + cell count was 69.4/µL in the adequate mobilization group and 46/µL in the mobilization failure group (p < 0001). Multivariate analysis revealed that donor/recipient weight ratio and the 4th day peripheral CD34 + cell count≥ 50/µL were independent markers for 4th day collection success. A predictive model of our center including these parameters was available with 0.765 sensitivity and 0.968 specificity [(AUC):0.948 (95 % CI, 0.90-0.99), p < 0.001]. CONCLUSION: The result of the current study shows that peripheral 4th day collection can be performed in selected donors, taking into account peripheral CD34+ cell count and donor/recipient weight ratio. In addition, using these indicators, new predictive models can be created that may assist clinicians in daily practice.

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Chimeric Antigen Receptor (CAR) T cell therapy is a type of adoptive immunotherapy that offers a promising avenue for enhancing cancer treatment since traditional cancer treatments like chemotherapy, surgery, and radiation therapy have proven insufficient in completely eradicating tumors, despite the relatively positive outcomes. It has been observed that CAR-T cell therapy has shown promising results in treating the majority of hematological malignancies but also have a wide scope for other cancer types. CAR is an extra receptor on the T-cell that helps to increase and accelerate tumor destruction by efficiently activating the immune system. It is made up of three domains, the ectodomain, transmembrane, and the endodomain. The ectodomain is essential for antigen recognition and binding, whereas the co-stimulatory signal is transduced by the endodomain. To date, the Food and Drug Administration (FDA) has granted approval for six CAR-T cell therapies. However, despite its remarkable success, CAR-T therapy is associated with numerous adverse events and has certain limitations. This chapter focuses on the structure and function of the CAR domain, various generations of CAR, and the process of CAR-T cell development, adverse effects, and challenges in CAR-T therapy. CAR-T cell therapy also has scopes in other disease conditions which include systemic lupus erythematosus, multiple sclerosis, and myocardial fibrosis, etc.

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Hospitalist-run procedure teams enable expedited care in the inpatient setting. However, wait times for outpatient interventional radiology (IR) are long at our institution. Our study thus aims to compare the safety and wait times between procedural teams and IR placement of outpatient temporary hemodialysis catheters (THDC) for patients undergoing Chimeric antigen receptor T-cell (CAR-T) therapy apheresis. A retrospective chart review was conducted on all patients receiving outpatient THDC for CAR-T therapy from August 2019 until November 2022. During our study period, only 7 of the central lines were placed by IR, while 75 were placed by the procedure service. The average wait time from CAR-T consenting to procedure was 8.9 days for the procedure service and 14.7 days for IR. The 30 day minor complication rate was low - 2.7% in the procedure group, and 0% in the IR group. No major complications were noted in either group.

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Acute lymphoblastic leukemia (ALL) in pediatric patients typically presents with recognizable symptoms such as fever, pallor, and bone pain. However, atypical manifestations can complicate the diagnostic landscape. We present a unique case of a seven-year-old male with T-cell ALL whose presenting symptom was priapism. This case underscores the need for heightened awareness among healthcare professionals regarding the diverse clinical presentations of leukemia, emphasizing the importance of a multidisciplinary team approach for comprehensive evaluation and management. Our seven-year-old patient presented with priapism. A comprehensive diagnostic workup, including complete blood counts and subsequent bone marrow examination, led to the diagnosis of T-cell ALL. Given the rare presentation, a multidisciplinary team consisting of pediatric oncologists/hematologists, urologists, and other relevant specialists collaborated to formulate a tailored treatment plan. The patient received an intensified chemotherapy regimen, resulting in the resolution of priapism and hematologic improvement. Priapism as an initial presentation of T-cell ALL in a pediatric patient is an exceptional occurrence, necessitating a specialized and collaborative approach to diagnosis and management. This case report highlights the importance of interdisciplinary coordination involving pediatric oncologists and urologists in addressing the unique challenges posed by atypical leukemia presentations. The rarity of this manifestation emphasizes the need for further research to elucidate the underlying mechanisms and establish optimal management strategies for similar cases.

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Chimeric antigen receptor (CAR) T-cell therapies are increasingly adopted as a commercially available treatment for hematologic and solid tumor cancers. As CAR-T therapies reach more patients globally, the cryopreservation and banking of patients' leukapheresis materials is becoming imperative to accommodate intra/inter-national shipping logistical delays and provide greater manufacturing flexibility. This study aims to determine the optimal temperature range for transferring cryopreserved leukapheresis materials from two distinct types of controlled rate freezing systems, Liquid Nitrogen (LN2)-based and LN2-free Conduction Cooling-based, to the ultracold LN2 storage freezer (≤-135 °C), and its impact on CAR T-cell production and functionality. Presented findings demonstrate that there is no significant influence on CAR T-cell expansion, differentiation, or downstream in-vitro function when employing a transfer temperature range spanning from -30 °C to -80 °C for the LN2-based controlled rate freezers as well as for conduction cooling controlled rate freezers. Notably, CAR T-cells generated from cryopreserved leukapheresis materials using the conduction cooling controlled rate freezer exhibited suboptimal performance in certain donors at transfer temperatures lower than -60 °C, possibly due to the reduced cooling rate of lower than 1 °C/min and extended dwelling time needed to reach the final temperatures within these systems. This cohort of data suggests that there is a low risk to transfer cryopreserved leukapheresis materials at higher temperatures (between -30 °C and -60 °C) with good functional recovery using either controlled cooling system, and the cryopreserved materials are suitable to use as the starting material for autologous CAR T-cell therapies.

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BACKGROUND: In patients with relapsed or refractory B cell acute lymphoblastic leukemia or B cell non-Hodgkin lymphoma (r/r B-ALL/B-NHL) with low CD3+ cells in the peripheral blood (PB), sufficient CD3+ cell yield in a single day may not be obtained with normal-volume leukapheresis (NVL). Large-volume leukapheresis (LVL) refers to the processing of more than three times the total blood volume (TBV) in a single session for PB apheresis; however, the efficiency and safety of LVL for manufacturing of tisagenlecleucel (tisa-cel) remain unclear. This study aimed to investigate the tolerability of LVL. STUDY DESIGN AND METHODS: We retrospectively collected data on LVL (≥3-fold TBV) and NVL (<3-fold TBV) performed for patients with r/r B-ALL/B-NHL in our institution during November 2019 and September 2023. All procedures were performed using a continuous mononuclear cell collection (cMNC) protocol with the Spectra Optia. RESULTS: Although pre-apheresis CD3+ cells in the PB were significantly lower in LVL procedures (900 vs. 348/µL, p < .01), all patients could obtain sufficient CD3+ cell yield in a single day with a comparably successful rate of final products (including out-of-specification) between the two groups (97.2% vs. 100.0%, p = 1.00). The incidence and severity of citrate toxicity (no patients with grade ≥ 3) during procedures was not significantly different between the two groups (22.2% vs. 26.1%, p = .43) and no patient discontinued leukapheresis due to any complications. CONCLUSION: LVL procedures using Spectra Optia cMNC protocol was well tolerated and did not affect the manufacturing of tisa-cel.

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T-cell acute lymphoblastic leukemia (T-ALL) is a rare hematologic malignancy with a unique set of clinical challenges when it occurs in adults. This case report presents the complex management of a 32-year-old male with T-ALL who developed symptomatic hyperleukocytosis and tumor lysis syndrome. Upon presentation, the patient exhibited a constellation of critical clinical and laboratory findings, including leukocytosis, anemia, thrombocytopenia, hyperkalemia, high-anion gap metabolic acidosis, and acute kidney injury. Despite an initial diagnosis of an allergic reaction, the subsequent course of the disease necessitated rapid medical intervention and consultation with multiple specialties, including hematology-oncology and nephrology. The challenges encountered in managing this patient's condition, particularly in an intensive care unit setting, underscored the need for a tailored and multidisciplinary approach. Treatment modalities included leukapheresis, continuous renal replacement therapy, aggressive fluid resuscitation, and chemotherapy. The case highlights the intricate decision-making processes and adaptability required when addressing T-ALL with hyperleukocytosis and tumor lysis syndrome, particularly in cases where conventional chemotherapy is contraindicated. This report underscores the importance of ongoing research and the need for standardized treatment protocols for such complex clinical scenarios.

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The majority of adoptive cellular therapies are produced from peripheral mononuclear cells obtained via leukapheresis and further enriched for the cells of interest (e.g., T cells). Here, we present a first-of-its-kind closed system, which effectively removes ~85% of monocytes and ~88% of platelets, while recovering ~88% of concentrated T cells in a separate output stream, as the leukapheresis sample flows through a microfluidic device at 5 mL/min. The system is driven by a common peristaltic pump, enabled by a novel pressure wave dampener, and operates in a closed bag-to-bag configuration, without requiring any specialized, dedicated equipment. When compared to standard density gradient centrifugation on paired samples, the new system demonstrated a 1.5-fold increase in T cell recovery and a 2-fold reduction in inter-sample variability for this separation outcome. The T cell-to-monocyte ratio of the leukapheresis sample was increased to 20:1, whereas with density gradient processing it decreased to 2:1. As a result of superior purity and/or gentler processing, T cells enriched by the system showed a 2.7-times higher fold expansion during subsequent culture, and an overall 3.5-times higher cumulative yield. This centrifugation-free and label-free closed system for enriching lymphocytes could significantly simplify and standardize the manufacturing of life-saving cellular therapies.

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INTRODUCTION: Peripheral blood stem cell (PBSC) harvesting requires reliable and safe vascular access. In our institution, a change of practice was implemented and the central venous catheter (CVC) placement for all autologous PBSC collections was abandoned in favor of a careful evaluation of peripheral venous access (PVA) for each individual patient. The aim of this prospective study was to evaluate the rate of patients with adequate peripheral veins for autologous PBSC collection and compare patient characteristics, collection efficacy, and complication rate between patients with PVA and CVC. METHOD: Peripheral veins were assessed by the apheresis nurse team in all patients referred between January 2020 and July 2021 to autologous PBSC collection. Only in case of difficult venous access, CVC was inserted. Large volume leukapheresis (LVL) procedures, which processed ≥3 total blood volumes, were performed. RESULTS: In 65 (57%) patients PVA was used, while 49 (43%) patients required placement of short-term CVC. Peripheral venous access was successfully used significantly more often in males (69.8%) (P = 0.010), and patients with multiple myeloma (71.0%) than in patients with non-Hodgkin's lymphoma (35.9%) and Hodgkin's lymphoma patients (33.3%) (P < 0.001). There was a significant difference in the type of prior administered chemotherapy; in the patients who received cytostatics free chemotherapy, PVA was used more often (75.0%) (P = 0.007). In terms of the efficacy and safety of LVLs, there were no differences between procedures performed using PVA and CVCs. CONCLUSION: Peripheral venous access is feasible for autologous PBSC collection in more than a half of patients, in particular in those with multiple myeloma. Changes in the treatment of multiple myeloma, using new proteasome inhibitors-based and immunomodulatory agents that do not adversely affect peripheral veins, have enabled the use of PVA even at the high blood flow rates required by LVL. Peripheral venous access is not associated with safety issues or with a lesser collection efficiency, and it is cost-effective as well. Each patient referred to autologous PBSC collection needs to be evaluated individually by the experienced apheresis team for the most appropriate venous access.

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BACKGROUND AIMS: Since the standardization of CD34 measurement by flow cytometry, predictors of leukapheresis CD34 yield have played a pivotal role in planning donor leukaphereses. We describe here a single institution's experience with a multivariate predictor that was used for 2,929 products without alteration for 20 years. METHODS: The ordinary least squares regression model variables included log peripheral CD34 count, collection duration (3- versus 4-hours), collection number, donor sex, and transplant type. RESULTS: During the study period we changed flow cytometers twice and leukapheresis instruments once. During the Cobe Spectra era the predictor explained 90% of the variability in CD34 collection yield for autologous transplants (r2 = 0.90), and 70% for allogeneic transplants with an overall sensitivity to predict a CD34 yield of ≥ 1 × 106/kg of 97.7%, and specificity of 81.4%. CONCLUSIONS: Implemented prospectively with real-time result reporting, the model allowed us to predict CD34 yield with both 3- and 4-hour collection scenarios. Given this guidance, 3-hour collections were selected by the clinical team 25% of the time, saving patient leukapheresis time and resources. When faced with a prediction of < 1 × 106 CD34/kg, the clinical team chose to defer collection 72% of the time. In instances where leukapheresis was performed despite a poor predicted outcome, 85% of patients collected on the Cobe Spectra, and 92% of patients collected on the Optia, failed to collect at least 1 × 106 CD34/kg. A revised model is tested retrospectively on Optia data, and suggestions for further improvements are discussed.

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Objective Several institutions outsource CD34+ cell counting of leukapheresis products, limiting rapid measurements, as results are obtained the next day. This problem is compounded with plerixafor use, a stem cell-mobilizing drug that increases leukapheresis efficiency but requires administration the day before leukapheresis. Use of this drug for a second leukapheresis procedure before the first-day leukapheresis CD34+ count results are confirmed causes unnecessary leukapheresis and expensive plerixafor administration. We investigated whether or not measuring hematopoietic progenitor cells in leukapheresis products (AP-HPCs) using a Sysmex XN-series analyzer could resolve this problem. Methods We retrospectively compared the absolute AP-HPC value per body weight with the CD34+ (AP-CD34+) count in 96 first-day leukapheresis product samples obtained between September 2013 and January 2021. Comparisons were also conducted according to regimen: granulocyte colony-stimulating factor (G-CSF) monotherapy, chemotherapy plus G-CSF, or plerixafor mobilization. Results AP-CD34+ and AP-HPC counts correlated strongly (rs=0.846) overall and, in particular, under chemotherapy plus G-CSF (rs=0.92) but correlated mildly under G-CSF monotherapy (rs=0.655). AP-HPCs could not completely be dichotomized based on an AP-CD34+ threshold of 2×106/kg for any stimulation procedure. In most cases with AP-HPCs >6×106/kg, the AP-CD34+ count exceeded 2.0×106/kg, but in 5.7% of these cases, the AP-CD34+ count was <2.0×106/kg. A cut-off of AP-HPCs >4.843×106/kg yielded a sensitivity of 71% and specificity of 96% for predicting AP-CD34+≥2×106/kg. Conclusion AP-HPCs can identify cases in which sufficient stem cells have been collected.

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BACKGROUND AIMS: Dendritic cell (DC)-based immunotherapy is a promising approach to treat cancer. However, key aspects governing the reproducible manufacturing of high-quality DC remain incompletely defined. Here, we show that the time window between leukapheresis and DC manufacturing is critical. METHODS: Transcriptomic profiling by RNA-seq was used to unbiasedly characterize cellular states during each step of DC manufacturing process, and functional assays were used to determine the anti-tumor activities of DC. RESULTS: During preclinical development of a DC-based cytotherapy platform, CUD-002 (NCT05270720), we found that DC quality varied among different batches, even though commonly used DC maturation markers CD80, CD83 and CD86 were indistinguishable. Multivariate analysis indicated that DC quality was negatively associated with the shipping time from the leukapheresis site to the manufacturing center. To investigate the potential effect of shipping time, we stored leukapheresis materials from three donors for 0, 1, 2 or 3 days before DC manufacturing. For each step, we carried out RNA-seq analysis to unbiasedly characterize cellular states. Integrated bioinformatic analyses indicated that longer storage time reduced the expression of several transcription factors to attenuate interferon pathways. CONCLUSIONS: Consistently, we found that 3-day storage of leukapheresis materials significantly lowered the efficiency to generate DC but also impaired DC responses to inflammatory signals, resulting in inferior antigen-presentation and cytotoxic T-cell activities. Thus, we recommend using leukapheresis materials within 48 h to manufacture therapeutic DCs.

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The clinical utility of circulating tumor cells (CTCs) is hampered by the low number of cells detected. Diagnostic leukapheresis (DLA) offers a solution but, due to the observed non-specific binding and clumping, processing of DLA samples using the CellSearch system only allows for the processing of aliquots consisting of ~ 2% of the total DLA sample per test. Here, we introduce a flow enrichment target capture Halbach-array (FETCH)-based separation method in combination with a DNase preprocessing step to capture CTCs from larger fractions of DLA products without clumping. To evaluate the FETCH method, we processed peripheral blood samples from 19 metastatic castration-naïve prostate cancer (mCNPC) patients with CellSearch, and processed 2% aliquots of leukapheresis samples from the same patients with CellSearch as well as FETCH with or without DNase preprocessing. Using 2% aliquots from six patients, the use of FETCH with fewer immunomagnetic epithelial cellular adhesion molecule (EpCAM) conjugated ferrofluids was tested, whereas 20% aliquots from four patients were used to evaluate the processing of 10-fold larger DLA samples using FETCH. Results show that the cell clumping normally seen after immunomagnetic enrichment of DLA material was greatly reduced with the use of DNase pretreatment, while the number of CTCs detected was not affected. The number of CTCs detected in 2% aliquots of DLA using FETCH was unchanged compared to CellSearch and did not decrease when using down to 10% of the volume of immunomagnetic anti-EpCAM ferrofluids normally used in a CellSearch test, whereas the number of co-enriched white blood cells reduced a median 3.2-fold. Processing of a 20% aliquot of DLA with FETCH resulted in a 14-fold increase in CTCs compared to the processing of 2% aliquots of DLA using CellSearch and a total 42-fold median increase in CTCs compared to peripheral-blood CellSearch.

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Acute myeloid leukemia (AML), the most common form of acute leukemia, is an aggressive lethal hematological malignancy that mainly occurs in older adults with a slightly higher predominance in males. It is prompted by the clonal expansion of immature myeloid blasts in the bone marrow, peripheral blood, and/or extramedullary tissues. Leukostasis in AML is a critical medical condition mainly affecting the lungs and brain and arises when tissue perfusion is compromised due to the clustering of white blood cells (WBCs) within the microvasculature. Cardiac involvement in this condition is exceptionally uncommon. Here, we present a case of a 56-year-old man, recently diagnosed with acute myelogenous leukemia M4 and leukostasis, who developed acute anterior ST-elevation myocardial infarction six days after presentation and in whom emergent coronary angiography showed proximal left anterior descending (LAD) artery lesion with a large clot obstructing the flow and thrombolysis in myocardial infarction (TIMI) I flow, and urgent percutaneous coronary intervention (PCI) was done; thromboaspiration and drug-coated balloon angioplasty were performed with good angiographic results. Antiplatelet (aspirin and clopidogrel) and anticoagulation (enoxaparin) were started immediately before PCI. Emergent leukapheresis was initiated in addition to hydroxyurea with complete resolution of chest pain. Four days post PCI, the patient developed right-sided hemiparesis with an evident infarct on a CT scan of the brain, and he also developed acute limb ischemia involving the distal right foot. Five days post PCI, the patient had a sudden sustained ventricular tachycardia followed immediately by asystole, and cardio-pulmonary resuscitation was done for 25 minutes but with no response.