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Summary: We adjusted haematopoietic stem and progenitor cell (HSPC) apheresis collection from patients with sickle cell disease (SCD) by targeting deep buffy coat collection using medium or low collection preference (CP), and by increasing anticoagulant–citrate–dextrose–solution A dosage. In 43 HSPC collections from plerixafor‐mobilized adult patients with SCD, we increased the collection efficiency to 35.79% using medium CP and 82.23% using low CP. Deep buffy coat collection increased red blood cell contamination of the HSPC product, the product haematocrit was 4.7% with medium CP and 6.4% with low CP. These adjustments were well‐tolerated and allowed efficient HSPC collection from SCD patients. [ABSTRACT FROM AUTHOR]

Study Objective: Alemtuzumab is a monoclonal antibody that targets the cell surface antigen CD52 on lymphocytes. Although it is used for the treatment of hematologic malignancies, such as chronic lymphocytic leukemia, and incorporated into many hematopoietic stem cell transplant (HSCT) conditioning regimens, few studies have evaluated the pharmacology of alemtuzumab in adult patients with sickle cell disease (SCD). We therefore examined the pharmacokinetics (PK) and pharmacodynamics (PD) of alemtuzumab in adults with SCD who received a matched related donor HSCT to determine if the clearance of alemtuzumab affects transplant outcomes. Design: PK and PD analysis of patient data from a single‐center clinical trial. Setting: Clinical research center. Patients: Twenty‐two adult patients with SCD who received one of two nonmyeloablative allogeneic HSCT regimens: alemtuzumab and total body irradiation (Alem‐TBI) or pentostatin, cyclophosphamide, alemtuzumab, and total body irradiation (Pento‐Cy‐Alem‐TBI). Measurements and Main Results: Alemtuzumab serum concentrations, absolute lymphocyte counts, T‐cell (CD3), and myeloid (CD14/15) chimerism were collected at distinct time points and analyzed. A semi‐mechanistic PK population model was built to understand inter‐individual differences in pharmacology. Alemtuzumab was detectable up to 28 days post‐HSCT. The mean alemtuzumab level 7 days after transplant for patients on Alem‐TBI was 818 ng/ml, significantly lower than the mean level of 1502 ng/ml for patients on Pento‐Cy‐Alem‐TBI (p < 0.001), but this difference decreased as time progressed. The clearance of alemtuzumab was linear, and the half‐life was longer in the Pento‐Cy‐Alem‐TBI group (average half‐life = 61.1 h) compared to the Alem‐TBI group (average half‐life = 44.1 h) (p < 0.001). The CD3 chimerism at 2 and 4 months after transplant positively correlated with alemtuzumab levels collected on day 14 after transplant (R2 = 0.40 and p = 0.004 at 2 months, R2 = 0.36 and p = 0.005 at 4 months), but this significance was lost by 6 months after HSCT. No correlation was seen between alemtuzumab levels and CD14/15 chimerism. Conclusion: Between 2 and 4 months after transplant, higher alemtuzumab levels measured 14 days after transplant correlated with patients having better engraftment, suggesting more lymphodepletion may be needed to reduce graft failure in these two non‐myeloablative matched related donor HSCT regimens. [ABSTRACT FROM AUTHOR]

Similar to SCD-CB CD34 SP + sp cells, we found no differences in erythroid cell differentiation in I HBB i -edited SCD-adult CD34 SP + sp cells at day 14 compared with mock-treated cells (Fig 1A-D). EN CRISPR/Cas9 sickle mutation CD34+ cells cord blood gene correction. e80 e84 5 09/02/21 20210901 NES 210901 Sickle cell disease (SCD) is an ideal model to investigate the potential use of gene editing to correct a point mutation on the -globin gene ( I HBB i ). HbF levels were also significantly increased in I HBB i -edited SCD-adult CD34 SP + sp cells (54-1 ± 3-3%) compared with mock-treated cells (16-0 ± 3-0%) ( I P i = 0-0001), while HbA2 levels were not significant difference between mock-treated cells (6-2 ± 1-4%) and I HBB i -edited SCD-adult CD34 SP + sp cells (8-9 ± 0-9%) ( I P i = 0-06). Comparison of CD34+ cells isolated from frozen cord blood and fresh adult peripheral blood of sickle cell disease patients in gene correction of the sickle mutation at late-stage erythroid differentiation. [Extracted from the article]

Summary: Stress erythropoiesis and chronic inflammation in subjects with sickle cell disease (SCD) may have an impact on the bone marrow (BM) haematopoietic stem and progenitor cell (HSPC) quality and yield necessary for effective autologous, ex vivo HSPC gene therapy. BM from 19 subjects with SCD and five volunteers without SCD (non‐SCD) was collected in different anticoagulants and processed immediately (day 0) or the following day (day 1). Inflammatory, contamination and aggregation markers within the mononuclear layer, and CD34, CD45 and Glycophorin‐A (GPA) expression on HSPCs after CD34+ selection were analysed by conventional and imaging flow cytometry. Compared to non‐SCD BM, multiple markers of inflammation, contamination (red cells, P < 0·01; platelets, P < 0·01) and aggregates (platelet/granulocytes, P < 0·01; mononuclear/red cells, P < 0·01) were higher in SCD BM. Total CD34+ cell count was lower in SCD BM (P < 0·05), however CD34+ count was higher in SCD BM when collected in acid citrate dextrose‐A (ACDA) versus heparin (P < 0·05). Greater than 50% of CD34+ HSPCs from SCD BM are CD34dim due to higher erythroid lineage expression (P < 0·01) as single cell CD34+CD45+GPA+ (P < 0·01) and CD34+CD45−GPA+ (P < 0·01) HSPCs. SCD BM is characterized by increased inflammation, aggregation and contamination contributing to significant differences in HSPC quality and yield compared to non‐SCD BM. [ABSTRACT FROM AUTHOR]

The observations that haematopoietic stem cells (HSCs) express vasopressin receptors and that patients with cDI were intermittently anaemic convinced us to study the effect of vasopressin on HSCs in vitro and in vivo. Dear Editor, We found Winzeler et al's paper1 on the effect of arginine vasopressin (AVP) in patients suffering from central diabetes insipidus (cDI) and primary polydipsia (PP) quite interesting. [Extracted from the article]

BACKGROUND: Cell number and viability are important in cord blood (CB) transplantation. While 10% dimethyl sulfoxide (DMSO) is the standard medium, adding a starch to freezing medium is increasingly utilized as a cytoprotectant for the thawing process. Similar to hetastarch, pentastarch has the advantages of faster renal clearance and less effect on the coagulation system. STUDY DESIGN AND METHODS: We compared a lower DMSO concentration (5%) containing pentastarch with 10% DMSO and performed cell viability assay, colony-forming units (CFUs), and transplantation of CB cells in NOD/SCID IL2Rγnull mice. RESULTS: CB cells in 5% DMSO/pentastarch had similar CD34+, CD3+, and CD19+ cell percentages after thawing as fresh CB cells. CB cells in 5% DMSO/pentastarch had higher viability (83.3 ± 9.23%) than those frozen in 10% DMSO (75.3 ± 11.0%, p < 0.05). We monitored cell viability postthaw every 30 minutes. The mean loss in the first 30 minutes was less in the 5% DMSO/pentastarch group. At the end of 3 hours, the viability decreased by a mean of 7.75% for the 5% DMSO/pentastarch and 17.5% for the 10% DMSO groups. CFUs were similar between the two cryopreserved groups. Frozen CB cells engrafted equally well in IL2Rγnull mice compared to fresh CB cells up to 24 weeks, and CB cells frozen in 5% DMSO/pentastarch engrafted better than those in 10% DMSO. CONCLUSION: Our data indicate that the lower DMSO concentration with pentastarch represents an improvement in the CB cryopreservation process and could have wider clinical application as an alternate freezing medium over 10% DMSO. [ABSTRACT FROM AUTHOR]

Mode exciters which consist of alternate concatenation of step-index (S) and graded-index (G) fibers are used widely for the measurement of transmission characteristics (optical loss and baseband frequency response) of multimode fibers. This paper presents a theoretical analysis for the mode exciters based on geometrical ray optics approximation. The mode power distribution controlling effect of the exciters, excited mode power distribution in the test fiber, and accuracy and reproducitibility of optical loss measurements are clarified theoretically. It is shown that optical loss measurements under steady-state distribution can be done by using either SGS or GSG mode exciters which consist of either small core or low NA fibers. [ABSTRACT FROM AUTHOR]

Primary aortoenteric fistula is very rare and a highly lethal entity. It is very important not to miss a few chances to diagnose it endoscopically. We report our experience of a case of primary aortoduodenal fistula. An 80-year-old woman complained of repeated hematemesis, bloody bowel discharge, and hemorrhagic shock. An abdominal aortic aneurysm was detected by an abdominal angiography. Duodenoscopy was performed 3 and 5 days after hematemesis, showing two different patterns of endoscopic findings. Three days after hematemesis, an undermining ulcer with a dark red clot at its bottom was detected in the third part of the duodenum. Five days after hematemesis, the base of the ulcer was covered with yellowish matter on the red clot. Six days after hematemesis, aortoduodenal fistula was confirmed in the third part of the duodenum at surgery. An ulcer with yellowish matter as well as with a red clot in the third and fourth parts of the duodenum by endoscopy might be indicative of aortoduodenal fistula. [ABSTRACT FROM AUTHOR]