Analysis of CD34+ cell subsets in stem cell harvests can more reliably predict rapidity and durability of engraftment than total CD34+ cell dose, but steady state levels do not correlate with bone marrow reserve

In peripheral blood stem cell transplantation (PBSCT), the number of CD34+ cells transplanted has been shown to correlate well with both rapidity and durability of engraftment. However, it is clear that engraftment does not necessarily correlate with total CD34+ cell numbers in some patients. Consequently, there is increasing interest in evaluating the role of CD34+ subsets in haemopoietic recovery as a more accurate marker of harvest quality. We analysed the numbers of CD34+ cell subsets, namely Thy-1+, L-Selectin+ and CD38-, and correlated this with engraftment in 86 patients undergoing PBSCT. Adequate engraftment was defined as being a platelet count greater than 50 x 10(9)/l and a neutrophil count greater than 1.0 x 10(9)/l. CD34+L-Selectin+ provided the best prediction of engraftment rapidity, although the improvement over total CD34+ cell dose was minor. Only the dose of CD34+Thy-1+ cells transplanted correlated with durable engraftment. The probability of adequate 3-month engraftment increased with the dose of CD34+ cells transplanted, but 10% of patients receiving > 5 x 10(6)/kg still showed poor engraftment at 3 months. However, all patients receiving > 2.5 x 10(5)/kg CD34+Thy-1+ showed adequate engraftment at this time point. We also demonstrated that CD34+Thy-1+ progenitors were restricted to the bone marrow under normal conditions and, during stem cell mobilization, their kinetics generally paralleled total CD34+ numbers.     

A comparative study of adverse reactions occurring after administration of glycosylated granulocyte colony stimulating factor and/or dexamethasone for mobilization of neutrophils in healthy donors

Both granulocyte colony-stimulating factor (G-CSF) and dexamethasone (DXM) are used for neutrophil (PMN) mobilization and collection. This prospective study was aimed to evaluate and compare the rate, severity and clinical significance of adverse reactions of these drugs alone and in combination in healthy donors. PMN mobilization was carried out using dexamethasone alone (8 mg orally; n=25) or glycosylated G-CSF alone (Lenograstim, 5 g/kg subcutaneously, n=24) or in combination (n=23) prior to a standard granulocyte apheresis on the Spectra cell separator. The number of PMNs counted in the mobilized peripheral blood of the donors was 7.0 (3.6–20.4) ×10⁹/L (DXM), 25.2 (15.5–49.7) ×10⁹/L (G-CSF), and 31.6 (20.0–43.0) ×10⁹/L (G-CSF+DXM), corresponding to PMN apheresis yields of 13 (8–43) ×10⁹/U, 56 (34–118) ×10⁹/U, and 83 (33–117) ×10⁹/U, respectively. The three groups had comparable percentages of donors with at least one adverse effect (ranging from 75 to 80%), but the G-CSF-containing regimens were generally more toxic, as was reflected by higher percentages of donors with moderate to severe adverse reactions and higher overall severity scores of 2.28 (G-CSF) and 2.08 (G-CSF+DXM) compared with 1.33 in the DXM group (p0.001). With G-CSF alone, pain symptom complexes were more frequent, more severe, and more often triggered requests for analgesics (9/47 donors; 19%) and unwillingness to give further neutrophil donations (2/47 donors; 4%). The addition of DXM to G-CSF diminished some symptoms, particularly bone pain, headache and the frequency of requests for analgesics. The predominant symptoms in the DXM alone group were mild gastrointestinal complaints. We conclude that G-CSF stimulation improved neutrophil mobilization and apheresis yields at the expense of donor tolerability. Compared with G-CSF alone, the combination G-CSF and DXM did not increase the quantity or the severity of donor symptoms.Abbreviations AP Alkaline phosphatase - LDH Lactic dehydrogenase - DBV Donor blood volume - DXM Dexamethasone - G-CSF Granulocyte colony-stimulating factor - HCT Hematocrit - PMN Polymorphonuclear neutrophil leukocytes - OSS Overall severity score - p.o. Orally - s.c. Subcutaneously - WBC White blood cells     

Ozone production by amino acids contributes to killing of bacteria

Reactive oxygen species produced by phagocytosing neutrophils are essential for innate host defense against invading microbes. Previous observations revealed that antibody-catalyzed ozone formation by human neutrophils contributed to the killing of bacteria. In this study, we discovered that 4 amino acids themselves were able to catalyze the production of an oxidant with the chemical signature of ozone from singlet oxygen in the water-oxidation pathway, at comparable level to antibodies. The resultant oxidant with the chemical signature of ozone exhibited significant bactericidal activity in our distinct cell-free system and in human neutrophils. The results also suggest that an oxidant with the chemical signature of ozone produced by neutrophils might potentiate a host defense system, when the host is challenged by high doses of infectious agents. Our findings provide biological insights into the killing of bacteria by neutrophils.     

自体骨髓干细胞动员治疗大鼠实验性心肌梗死

目的研究应用粒细胞集落刺激因子(GCSF)动员自体骨髓干细胞对大鼠实验性心肌梗死的治疗作用。方法应用冠状动脉结扎的大鼠心肌梗死模型,给予GCSF动员自体骨髓干细胞,于大鼠心肌梗死后1周测外周血CD34 细胞含量,并用免疫组化染色观察心肌梗死区的CD34 细胞浸润情况。于梗死后4周用HE和免疫组化染色及血流动力学监测评价实验大鼠的心肌梗死面积,血管密度和心功能。结果心肌梗死后1周,GCSF组大鼠外周血CD34 细胞含量明显高于对照组,心肌梗死交界处见CD34 细胞浸润。4周后,与对照组相比,GCSF组心肌梗死范围减小,新生血管增多,心功能改善。结论应用GCSF动员自体骨髓干细胞对大鼠实验性心肌梗死有明确的治疗作用。     

动态关节松动术结合离心训练对肱骨外上髁炎的疗效观察

目的:观察动态关节松动术结合离心训练对肱骨外上髁炎的治疗效果。方法:选取40例肱骨外上髁炎患者随机分成对照组、观察组各20例,对照组采用Biodex等速训练仪进行腕背伸肌离心训练,观察组在接受上述治疗的基础上,同时接受肘关节动态关节松动治疗。在治疗前和治疗4周后分别对各组患者采用视觉模拟量表(VAS)、无痛握力(PFG)及网球肘分级评定(PRTEE)进行临床疗效评估。结果:治疗4周后,2组患者VAS评分、PRTEE疼痛、功能及总分均较治疗前明显降低(均P<0.05),且观察组更低于对照组(P<0.05)。治疗后,2组PFG评分均明显高于治疗前(均P<0.05),且观察组更高于对照组(P<0.05)。结论:动态关节松动结合离心训练对肱骨外上髁炎患者疗效明显,可有效改善患者疼痛及日常生活活动能力,值得临床推广使用。     

Does myeloma genetic have an effect on stem cell mobilization?

BackgroundAutologous stem cell transplantation (ASCT) after induction treatment is the standard of care. Our understanding of myeloma genetics has been very limited and its effect to stem cell mobilization is not widely investigated. We aimed to investigate the effect of genetic abnormalities on stem cell mobilization in myeloma.MethodsThe data of 150 MM patients who underwent stem cell mobilization at our center between 2009–2020 were included and analyzed retrospectively. Pre-treatment bone marrow cytogenetics and fluorescence in situ hybridization tests were performed for each patient.ResultsGroups were divided into two as patients with normal cytogenetic and abnormal cytogenetic. No difference observed between groups regarding age, gender and ECOG (p = 0.4; p = 0.2; p = 0.3). Groups were similar concerning myeloma characteristics, received treatment and treatment response. Median CD34+ cells/kg harvested was 444(2−11.29) in normal cytogenetic group whereas it was 4,8(2.4−8.6) in abnormal cytogenetic group(p = 0.2). Optimal CD34+ cells level achievement was 73 (67 %) in normal cytogenetic group while it was 25(71.4 %) in abnormal cytogenetic group(p = 0.6). Neutrophil and platelet engraftment durations were similar among cytogenetic groups (p = 0.7; p = 0.9). R-ISS based groups were also did not differ regarding harvested CD34+ cells and achievement optimal CD34 level (p = 0.79, p = 0.74). Engraftment durations for neutrophil and platelet were comparable between R-ISS based groups (p = 0.59, p = 0.65)ConclusionsHere we were not able to find any impact of genetic abnormalities on stem cell mobilization in myeloma patients. Expanded studies can aid to identify the effect of particular genetic anomalies on the stem cell mobilization.     

Engraftment after autologous hematopoietic stem cell transplantation in patients mobilized with Plerixafor: A retrospective,multicenter study of a large series of patients

Plerixafor (PLX) appears to effectively enhance hematopoietic stem-cell mobilization prior to autologous hematopoietic stem cell transplantation (auto-HCT). However, the quality of engraftment following auto-HCT has been little explored. Here, engraftment following auto-HCT was assessed in patients mobilized with PLX through a retrospective, multicenter study of 285 consecutive patients. Information on early and 100-day post-transplant engraftment was gathered from the 245 patients that underwent auto-HCT. The median number of PLX days to reach the stem cell collection goal (≥2 × 10⁶ CD34⁺ cells/kg) was 1 (range 1–4) and the median PLX administration time before apheresis was 11 h (range 1–18). The median number of apheresis sessions to achieve the collection goal was 2 (range 1–5) and the mean number of CD34⁺ cells collected was 2.95 × 10⁶/kg (range 0–30.5). PLX administration was safe, with only 2 mild and transient gastrointestinal adverse events reported. The median time to achieve an absolute neutrophil count (ANC) >500/μL was 11 days (range 3–31) and the median time to platelet recovery >20 × 10³/μL was 13 days (range 5–69). At 100 days after auto-HCT, the platelet count was 137 × 10⁹/L (range 7–340), the ANC was 2.3 × 10⁹/L (range 0.1–13.0), and the hemoglobin concentration was 123 g/L (range 79–165). PLX use allowed auto-HCT to be performed in a high percentage of poorly mobilized patients, resulting in optimal medium-term engraftment in the majority of patients in whom mobilization failed, in this case mainly due to suboptimal peripheral blood CD34⁺ cell concentration on day +4 or low CD34⁺ cell yield on apheresis.