Pure Red Cell Aplastic Anemia Research Articles

纯红细胞再生障碍性贫血的诊断与治疗进展

纯红细胞再生障碍性贫血的诊断与治疗进展

Clinical analysis of 67 cases of pure red cell aplastic anemia

目的总结纯红细胞再生障碍（PRCA）的继发因素、实验室特点、治疗方案及预后。方法本研究为多中心回顾性临床研究，纳入2010年6月1日至2019年6月1日初诊的18岁以上PRCA患者进行随访，并根据不同治疗方案与药物减量速度等进行疗效、生存的比较分析。结果共纳入67例PRCA患者，其中继发性PRCA占44.8%（30/67），最常见的基础疾病为胸腺瘤（10例）和T细胞大颗粒淋巴细胞白血病（6例）。PRCA患者总缓解率（ORR）为85.7%，3年总体生存（OS）率为（74.3±7.5）%。单用环孢素A治疗缓解率稍高于单用激素或环孢素A联合糖皮质激素[90.0%（36/40）对75.0%（12/16），P=0.147]。环孢素A治疗达完全缓解或部分缓解3~6个月后，每次减量25 mg/d，减量间隔≥1个月组中位无病生存时间长于减量间隔<1个月组[未达到对15（95% CI 7~23）个月，P<0.001]。有62.5%（10/16）患者复发后按初始治疗方案或增加剂量再次治疗仍有效。结论PRCA可发生于多种疾病，缓解率与生存率高，单用环孢素A治疗效果好，起效且稳定后需缓慢减量以降低复发率。

CongenitalSTAT3mutation Mediates Primary Persistent Polymorphic Inflammatory Activation and T Cell Leukemogenesis

Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathways play a pivotal role in inflammation and immunity, among which, JAK/STAT3 pathway is the most potent and leads the crosstalk of immunity and oncogenesis. Somatic STAT3 activatingmutations have been found in about 40% of T cell large granular lymphocytic leukemia (T-LGLL) patients, most of which are located in exon 21 which encodes Src homology 2 (SH2) domain leading to the increased activity of aberrant STAT3 protein and the upregulation of its transcriptional targets. While germline STAT3activatingmutations represent a newly defined entity of immune dysregulations named infantile-onset multisystem autoimmune disease-1 (ADMIO1, #MIM 615952). Both the two diseases are rare and poorly understood. Here, we report a pedigree including a proband, a six-year-old girl, primarily manifesting as thrombocytopenia and lymphadenopathy and her father diagnosed as T-LGLL with pure red cell aplastic anemia without autoimmune disorders preceding or during his disease course. Morphology of the bone marrow smears of the proband indicated normal hyperplasia without evident dyspepsia or increased blast cells. However, the vacuoles in monocytes and the density and size of granules in neutrophils increased, and megaloblast transformation was observed in some neutrophils. (Fig. 1A, 1B) Biopsy of an enlarged lymph node showed the reactive follicular hyperplasia. (Fig. 1C) Whole exon sequencing and pedigree analysis of the family revealed the germline STAT3 c.833G&gt;A/p.R278Hmutation harbored by the proband which originated de novo from her father who additionally carried a germline TAL1G62Rmutation and somatically accumulated an FLT3-ITD mutation. (Fig. 2) Through single-cell RNA sequencing, we also found the increase of circulating CD8+ T cells and the decrease of NK cells of the proband. (Fig. 3) The STAT3 target genes were generally overactivated, and the expression of cytokines decreased in transcription level. In the genes participating in JAK/STATs pathways, the expression of JAK3, STAT1, and STAT3was up-regulated significantly. (data not shown) Immunophenotype of the proband by flow cytometry confirmed change in immunocyte compartments, (Fig. 4) but the serum cytokine concentrations measured by flow cytometry yielded controversial results, that most of cytokines were moderately elevated, and IL-1β, IL-5, TNF-α, and IFN-γ were of the most evident. (data not shown) During the treatment and follow-up, Cyclosporin A (CsA) was efficient in maintaining her circulating platelets in the range of 166×109/L to 302×109/L, but the enlarged lymph nodes and hepatosplenomegaly had no response. Eleven months later, CsA was replaced by tacrolimusfor the severe gingival hyperplasia, which has efficiently stabilized her platelets count and normalized the enlarged lymph nodes, liver, and spleen. On the contrary, in the three and a half years' span of illness, the father was refractory to CsA and methotrexate (MTX), moreover, lethal bone marrow suppression was induced by one course of fludarabine. For the high level of HLA-I and HLA-II antibodies in the circulation, plantlets transfusions were only efficient after plasmapheresis. The father eventually died from pulmonary and gastrointestinal infection due to the failure of maternal HLA-haploidentical hematopoietic stem cell transplantation (HSCT). We comprehensively elaborated the immunophenotype of the proband and thoroughly elucidated the genetic alternations of the father which led to the T cell leukemogenesis, which brought new insight on these two rare diseases and highlighted a more scrupulous therapeutic strategy in T-LGLL with congenital mutations. Figure 1 Disclosures No relevant conflicts of interest to declare.

Significance of clonal TCR gene rearrangement in acquired pure red cell aplastic anemia

To evaluate the significance of T-cell antigen receptor (TCR) gene rearrangement among patients with acquired pure red cell aplastic anemia (A-PRCA). For 16 patients with A-PRCA, an immunosuppressive regimen based on cyclosporin A (CsA) was applied. Rearrangement of the TCR gene was detected by PCR, and T lymphocyte subsets in peripheral blood specimens was detected with flow cytometry. Five patients had presented with TCR clonal rearrangement and were positive for both TCR γ and TCR δ. The blood of 13 patients have returned to normal with the treatment, which included 3 cases with bone marrow returning to normal. In 7 cases, the red cell hyperplasia of bone marrow is still down, but has increased with the treatment. Three patients were close to cure, 7 showed remission, 3 were improved, but 3 were ineffective. The rate of effective treatment in those with TCR rearrangement (2/5) was significantly lower than that those without (11/11, chi-square=8.123, P < 0.05). Compared with those without the TCR gene rearrangement, the Th cells and proportion of Th/Ts were significantly lower, while the Ts cell (CD3+CD8+) were significantly higher in those with the rearrangement (P < 0.05). TCR gene rearrangement may play a role in the pathogenesis of A-PRCA. CsA is effective for the treatment of A-PRCA, but patients presenting clonal TCR gene rearrangement may response poorly to the treatment.

Analysis of blood cell autophagy distribution in hematologic diseases by transmission electron microscope

目的研究血细胞自噬在血液病中的分布特征及其可能病理机制。方法回顾性分析3 277例血液病患者电镜标本，利用透射电子显微镜观察血细胞自噬现象，分析血细胞自噬在血液病中的分布特点，结合临床检测和诊断结果分析其病理机制。结果检出15例患者伴有成熟粒细胞或有核红细胞自噬现象，其中骨髓增生异常综合征6例，急性白血病2例，再生障碍性贫血、纯红细胞再生障碍性贫血、地中海贫血、缺铁性贫血、淋巴瘤、多发性骨髓瘤和真性红细胞增多症各1例。15例患者中粒细胞自噬11例，有核红细胞自噬4例。9例伴细胞凋亡，6例伴细胞溶解，5例伴细胞巨幼样变。结论血液病成熟粒细胞和有核红细胞自噬多见于骨髓增生异常综合征，细胞凋亡、巨幼样变和溶解等病态造血可能诱发细胞自噬。

γδT Cell Is Impacted to Erythropoiesis Suppression in Patients with Acquired Pure Red Cell Aplastic Anemia.

Acquired pure red cell aplastic anemia(PRCA)is a group of heterogeneneous disorders characterized by erythropoiesis failure or disorder in bone marrow. PRCA is often associated with thymoma, large granular lymphocytic leukemia, and also some autoimmune diseases. It has been well documented that T cell subsets from the patients with PRCA often show some abnormalities either in quantum or in the effects to suppress erythropoiesis, and anemia symptom of the patients usually have a good response to cyclosporine treatment. So it suggested that activated T cell might play a key role in the pathogenesis of PRCA. This study is to explore the abnormalities of γδT cell subsets and the effects of immunosuppressive therapy in the PRCA patients.Methods: 12 patients, whose age ranged 37~72 years old, were diagnosed as PRCA based on bone marrow smear and biopsy, and were treated with cyclosporine, and 24 healthy adults were matched as normal controls. The three-color flowcytometry technique was used for lymphocytes subsets and γδT cells analyses. Furthermore, peripheral mononuclear cells (MNC) isolated from PRCA patients were cultured in RPMI1640 medium (106 cells/ml) with 10% FCS, phytohemagglutinin(PHA, 10μg/ml), and recombinant human interleukin-2(rIL-2, 50U/ml)for two weeks, then γδT cells were isolated with the TCRγδ Microbead Kit from cultured cells. The collected γδT cells were incubated with normal control bone marrow MNC in RPMI1640 medium (37°, 5% CO2 atmosphere) for CFU-E, CFU-GM, and BFU-E clones assay.Results: Comparing with control group, CD3+/CD8+ cells were increased significantly in the patients group (p<0.05), and the CD4+/CD8+ ratio was decreased and reversed. Furthermore, an increased Tc2 cells percentage and a decreased Tc1/Tc2 ratio were observed, and γδT cells were overrepresented in patients group(P<0.05). After treatment with cyclosporine, 10 of 12 patients got very good response (Hb recovered to over 100g/L), and in the responding patients, CD3+/CD8+ cells, Tc1 and Tc2 cells were decreased, and the ratio of CD4+/CD8+ and Tc1/Tc2 were return to normal respectively, and γδT cells were also decreased to normal range. Moreover, in vitro culture, the γδT cells isolated from PRCA patients show an inhibiting role to CFU-E and BFU-E but not to CFU-GM in a dose-dependent manner.Conclusion: Our study suggested that γδT cells might impacted to pathogenesis of acquired PRCA, a significant improvement of anemia symptoms had been shown after cyclosporine treatment, meanwhile, the percentage of γδT cells recovered to normal range, and it is very interesting, the γδT cells isolated from PRCA patients show an inhibiting role to CFU-E and BFU-E but not to CFU-GM in vitro culture. We think that it is an effective way to treat the patients with acquired PRCA by to rectify the abnormal cellular immunity.