Predictive value of thyroid function in severe aplastic anemia patients treated with immunosuppressive therapy.

To explore the predictive value of thyroid function in severe aplastic anemia (SAA) patients treated with immunosuppressive therapy (IST), 149 SAA patients in our center were enrolled between February 2015 and June 2020 in this study. We assessed the thyroid function of 134 patients without primary thyroid diseases, and discovered that 89 patients were accompanied by abnormal thyroid hormone, especially low triiodothyronine (T3). Patients with higher pretreatment-free T3 (FT3) levels (>5 pmol/L) demonstrated superior response rates at 3 and 6 months after IST compared to those with lower FT3 levels (54.5% vs 35.4%, P = .020; 67.3% vs 46.9%, P = .020). Multivariate analysis indicated that shorter disease duration (≤56 days) and response at 6 months were independent favorable factors of overall survival (relative risk [RR] = 2.66, 95% confidence interval [CI] = 1.03-6.90, P = .040; RR = 30.10, 95% CI = 4.02-225.66, P = .001). The 6-year failure-free survival (FFS) was 53.8% (95% CI = 40.9%-65.1%). Multivariate analysis revealed that patients with a response at 6 months, shorter duration (≤56 days) and receiving rabbit antithymocyte globulin (ATG) had better FFS outcomes than those without a response at 6 months, with a longer duration and receiving porcine ATG (RR = 22.6, 95% CI = 7.9-64.9, P < .001; RR = 2.4, 95% CI = 1.3-4.5, P = .006; RR = 2.5, 95% CI = 1.1-5.8, P = .030). In conclusion, FT3 levels reflect the severity of SAA, and patients with higher FT3 levels (>5 pmol/L) had superior response rates than those with lower ones.

Impaired immunosuppressive effect of bone marrow mesenchymal stem cell-derived exosomes on T cells in aplastic anemia.

BACKGROUND: Previous studies have verified the dysfunction of mesenchymal stem cells (MSCs) for immunoregulation in acquired aplastic anemia (AA) patients. Exosomes derived from MSCs can partially substitute MSCs acting as immune regulator. Dysfunction of exosomes (Exos) derived from AA-MSC (AA-Exos) may play a key role in immunologic dissonance. METHOD: In this study, CD3 + T cells were collected and cocultured with AA-Exos and exosomes derived from HD-MSC (HD-Exos). The proliferation, differentiation and activation of CD3 + T cells were detected to compare the immunosuppressive effects between AA-Exos and HD-Exos. An immune-mediated murine model of AA was structured to compare the therapeutic effect of AA-Exos and HD-Exos. Furthermore, total RNA including miRNA from exosomes we purified and total RNA of CD3 + T cells were extracted for RNA-seq in order to construct the miRNA-mRNA network for interactions and functional analysis. RESULTS: AA-Exos had impaired inhibition effects on CD3 + T cells in terms of cell proliferation, activation and differentiation compared with exosomes from HD-Exos. HD-Exos showed a more effective rescue of AA mice compared to AA-Exos. Importantly, we found some differentially expressed miRNA involved in immune response, such as miR-199, miR-128 and miR-486. The Gene Ontology analysis of differentially expressed genes (DEGs) revealed involvement of various cellular processes, such as lymphocyte chemotaxis, lymphocyte migration and response to interferon-gamma. The Kyoto Encyclopedia of Genes and Genomes analysis illustrated upregulation of critical pathways associated with T cell function after coculturing with AA-Exos compared with HD-Exos, such as graft-versus-host disease, Th17 cell differentiation and JAK-STAT signaling pathway. A miRNA-mRNA network was established to visualize the interaction between them. CONCLUSION: In summary, AA-Exos had impaired immunosuppressive effect on T cells, less ability to rescue AA mice and differently expressed miRNA profile, which might partly account for the pathogenesis of AA as well as provide a new target of AA treatment.

[Melatonin-Mediated Inhibitory Effect on Hyperimmune Status of Acquired Aplastic Anemia].

OBJECTIVE: To evaluate the expression level of melatonin and its effects on immune function in aplastic anemia (AA) patients. METHODS: The enzyme-linked immunosorbent assay (ELISA) was used to detect the plasma levels of melatonin in AA patients, and the correlation between melatonin levels and laboratory indexs was analyzed. The activation, proliferation, and apoptosis of T cells from AA patients were analyzed by flow cytometry with or without melatonin in vitro. RESULTS: The plasma levels of melatonin in AA patients were significantly lower compared with healthy controls (HC) (12.23 pg/ml vs 20.04 pg/ml, P < 0.01), while the plasma melatonin levels of AA patients in remission group after immunosuppressive therapy (IST) were significantly higher than those in non-remission group (29.16 pg/ml vs 11.73 pg/ml, P =0.04). Moreover, the melatonin levels were positively correlated with platelets (r =0.49), the absolute reticulocyte count (r =0.45), and the percentage of neutrophils (r =0.43). Meanwhile, there was a negative correlation between melatonin levels and the percentages of lymphocytes (r =-0.45). The expressions of CD25 and CD69 in both CD4+ and CD8+ T cells from AA patients were remarkably inhibited by melatonin in vitro (all P < 0.05). When cultured with melatonin, the proliferation rates of both CD4+ and CD8+ T cells from AA patients were markedly suppressed (P =0.01 andP < 0.01). CONCLUSION: The plasma levels of melatonin were decreased in AA patients, which might play an important role in the mechanism of immunological abnormalities. The hyperimmune status of AA patients could be partially ameliorated by melatonin in vitro.

[Deciphering Hypoplastic Myelodysplastic Syndrome and Aplastic Anemia via In-Depth Analysis of Lymphocyte Subsets].

OBJECTIVE: To explore the difference of lymphocyte subsets in peripheral blood (PB) between aplastic anemia (AA) and hypoplastic myelodysplastic syndrome (hypo-MDS) patients, meanwhile to compare the clinical parameters obtained from PB and bone marrow (BM). METHODS: The lymphocyte subsets in hypo-MDS (n=25) and AA (n=33) patients were investigated by flow cytometry. Meanwhile, the differences in PB cell counts, biochemical indicators, BM cell counts and abnormal chromosomes between the two groups were analyzed. RESULTS: The percentage of CD8+T cells in AA group was significantly higher than that in hypo-MDS group (P=0.001), while the percentage of CD4+ T cells and the CD4+/CD8+ ratio in AA group were obviously lower than those in hypo-MDS group (P=0.015 and 0.001, respectively). Furthermore, the proportion of CD4+ and CD8+ activated T (TA) cells, and memory Tregs in AA group was distinctly lower than those in hypo-MDS group (P=0.043, 0.015 and 0.024, respectively). Nevertheless, the percentage of CD8+ naive T (TN) cells in AA patients was remarkably higher (P=0.044). And hypo-MDS patients had declined lymphocyte counts (P=0.025), increased levels of total bilirubin (TBil), lactate dehydrogenase (LDH), vitamin B12 and proportion of BM blasts than AA patients (P=0.019, 0.023, 0.027 and 0.045, respectively). CONCLUSION: In this study it was confirmed that the percentages of CD4+ and CD8+ TA cells, memory Tregs and CD8+ TN cells were significantly different between AA and hypo-MDS patients, which provide an essential basis for the identification of these two diseases.

Association between human leukocyte antigen and immunosuppressive treatment outcomes in Chinese patients with aplastic anemia.

Background: Activated cytotoxic T cells (CTLs) recognize the auto-antigens presented on hematopoietic stem/progenitor cells (HSPCs) through class I human leukocyte antigen (HLA) molecules and play an important role in the immune pathogenesis of aplastic anemia (AA). Previous reports demonstrated that HLA was related to the disease susceptibility and response to immunosuppressive therapy (IST) in AA patients. Recent studies have indicated that specific HLA allele deletions, which helped AA patients to evade CTL-driven autoimmune responses and escape from immune surveillance, may lead to high-risk clonal evolution. Therefore, HLA genotyping has a particular predictive value for the response to IST and the risk of clonal evolution. However, there are limited studies on this topic in the Chinese population. Methods: To explore the value of HLA genotyping in Chinese patients with AA, 95 AA patients treated with IST were retrospectively investigated. Results: The alleles HLA-B*15:18 and HLA-C*04:01 were associated with a superior long-term response to IST (P = 0.025; P = 0.027, respectively), while the allele HLA-B*40:01 indicated an inferior result (P = 0.02). The allele HLA-A*01:01 and HLA-B*54:01 were associated with high-risk clonal evolution (P = 0.032; P = 0.01, respectively), and the former had a higher frequency in very severe AA (VSAA) patients than that in severe AA (SAA) patients (12.7% vs 0%, P = 0.02). The HLA-DQ*03:03 and HLA-DR*09:01 alleles were associated with high-risk clonal evolution and poor long-term survival in patients aged ≥40 years. Such patients may be recommended for early allogeneic hematopoietic stem cell transplantation rather than the routine IST treatment. Conclusion: HLA genotype has crucial value in predicting the outcome of IST and long-term survival in AA patients, and thus may assist an individualized treatment strategy.

Interleukin-10 promoter variability is associated with the susceptibility, severity, and clinical outcomes of aplasitc anemia in Han-Chinese population.

INTRODUCTION: Acquired aplastic anemia (AA), a heterogeneous bone marrow (BM) failure disease, is mainly mediated by the immune destruction of hematopoietic stem cells (HSCs). Given the predominant role of immunosuppressive therapy (IST) in AA, it is sensible to theorize that variants of cytokine genes might affect the outcome of IST. METHODS: In this study, we analyzed three single nucleotide polymorphisms (SNPs) of interleukin (IL)-10 gene in promoter region to clarify their relationship with susceptibility, clinical efficacy and prognosis of AA. RESULTS: We observed that CT genotype of IL-10 rs1800896 was associated with a decreased risk of AA (adjusted OR = 0.541 [95% CI 0.295-0.993], p = .047). Besides, the disease severity differed considerably by IL-10 gene promoter genotypes and alleles. Furthermore, IL-10 SNPs influenced efficacy of IST, with unfavorable response exhibited by rs1800871 and rs1800872 in dominant models (GG + AG vs. AA, adjusted OR = 0.409 [95% CI 0.178-0.943, p = .036] for rs1800871 and GG + GT vs. TT, adjusted OR = 0.396 [95% CI 0.173-0.909, p = .028] for rs1800872, respectively). CONCLUSION: The polymorphisms of IL-10 promoter region were informatively genetic risk factors which might be conducive to the insights into the mechanisms of AA and the design of individual regimens.

Quasi-Volatile MoS2 Barristor Memory for 1T Compact Neuron by Correlative Charges Trapping and Schottky Barrier Modulation.

Artificial neurons as the basic units of spiking neural network (SNN) have attracted increasing interest in energy-efficient neuromorphic computing. 2D transition metal dichalcogenide (TMD)-based devices have great potential for high-performance and low-power artificial neural devices, owing to their unique ion motion, interface engineering, and resistive switching behaviors. Although there are widespread applications of TMD-based artificial synapses in neural networks, TMD-based neurons are seldom reported due to the lack of bio-plausible multi-mechanisms to mimic leaking, integrating, and firing biological behaviors without external assistance. In this work, for the first time, a methodology is developed by introducing the hybrid effect of charge trapping (CT) and Schottky barrier (SB) in MoS2 FETs for barristor memory and one-transistor (1T) compact artificial neuron realization. By correlating the CT and SB processes, quasi-volatile and resistive switching behaviors are realized on the fabricated MoS2 FET and utilized to mimic the accumulating, leaking, and firing biological behaviors of neurons. Therefore, based on a single quasi-volatile CT-SB MoS2 barristor memory, a 1T compact neuron of the basic leaky-integral-and-fire (LIF) function is demonstrated without a peripheral circuit. Furthermore, a spiking neural network (SNN) based on the CT-SB MoS2 barristor neurons is simulated and implemented in pattern classification with high accuracy approaching 95.82%. This work provides a highly integrated and inherently low-energy implementation for neural networks.

Impaired immunosuppressive role of myeloid-derived suppressor cells in acquired aplastic anemia.

Myeloid-derived suppressor cells (MDSC) are a group of heterogeneous immature myeloid cells and display immunosuppressive function. In this study, MDSC populations were evaluated in acquired aplastic anemia (AA) (n=65) in which aberrant immune mechanisms contributed to bone marrow destruction. Our data demonstrate that both the proportion and immunosuppressive function of MDSC are impaired in AA patients. Decreased percentage of MDSC, especially monocytic MDSC, in the blood of AA patients (n=15) is positively correlated with the frequency of T-regulatory cells, bone marrow level of WT1 and decreased plasma level of arginase-1. RNA sequencing analyses reveal that multiple pathways including DNA damage, interleukin 4, apoptosis, and Jak kinase singnal transducer and activator of transcription are upregulated, whereas transcription, IL-6, IL-18, glycolysis, transforming growth factor and reactive oxygen species are downregulated in MDSC of AA (n=4), compared with that of healthy donors (n=3). These data suggest that AA MDSC are defective. Administration of rapamycin significantly increases the absolute number of MDSC and levels of intracellular enzymes, including arginase-1 and inducible nitric-oxide synthase. Moreover, rapamycin inhibits MDSC from differentiating into mature myeloid cells. These findings reveal that impaired MDSC are involved in the immunopathogenesis of AA. Pharmacologically targeting of MDSC by rapamycin might provide a promising therapeutic strategy for AA.

The novel SLC40A1 (T419I) variant results in a loss-of-function phenotype and may provide insights into the mechanism of large granular lymphocytic leukemia and pure red cell aplasia.

Variants in the solute carrier family 40 member 1 (SLC40A1) gene are the molecular basis of ferroportin disease, which is an autosomal dominant hereditary hemochromatosis. Here, we present a patient with pure red cell aplasia (PRCA) and large granular lymphocytic leukemia (LGLL) associated with an extremely high levels of serum ferritin and iron overload syndrome. Whole exon sequencing revealed a novel heterozygous variant in SLC40A1 (p.T419I), which was found in his daughter as well. A series of functional studies in vitro of the T419I variant in ferroportin were conducted and the results revealed a reduced capacity of iron export from cells without changes in protein localization and its sensitivity to hepcidin. Intracellular iron storage in mutated cells was significantly higher than that of wild-type. These findings suggest that the novel variant p.T419I can cause the classical form of ferroportin disease and an elevated intracellular iron level indicates a potential novel pathogenic mechanism underlying PRCA and LGLL.

Comparison of Hematopoietic Stem Cell Transplantation Outcomes Using Matched Sibling Donors, Haploidentical Donors, and Immunosuppressive Therapy for Patients With Acquired Aplastic Anemia.

We retrospectively compared the outcomes of 387 consecutive patients with acquired aplastic anemia (AA) who underwent hematopoietic stem cell transplantation (HSCT) with a fludarabine-based conditioning regimen from matched sibling donors (MSD) (n = 108) or haploidentical donors (HID) (n = 91) and immunosuppressive therapy (IST) (n = 188) from 2014 to 2020 at our hospital. Compared with HID-HSCT, MSD-HSCT had a lower incidence of graft failure (1% vs. 7%, p = 0.062), grade II-IV acute graft versus host disease (aGvHD) (16% vs. 35%, p = 0.001), and mild to severe chronic GvHD (cGvHD) (8% vs. 23%, p = 0.007), but an equivalent incidence of grade III-IV aGvHD (8% vs. 12%, p = 0.237) and moderate to severe cGvHD (3% vs. 9%, p = 0.076). HSCT had superior blood count recovery at 3, 6, and 12 months compared with IST (p < 0.001). The estimated 5-year overall survival (OS) of the MSD, HID, and IST groups were 86%, 72%, and 79% (p = 0.02), respectively; accordingly, the failure-free survival (FFS) rates were 85%, 68%, and 56%, respectively (p < 0.001). For patients aged ≤40 years, the OS rate was still significantly superior for MSD-HSCT receipients compared to HID-HSCT receipients (89% vs. 76%, p = 0.024) while the HID-HSCT recipients showed similar OS (76% vs. 78%, p = 0.166) but superior FFS (p = 0.047) when follow-up was longer than 14.5 months in contrast to IST. In a multivariate analysis, HID-HSCT and a conditioning regimen that included busulfan were adversely related to OS among patients who received allografts. In conclusion, MSD-HSCT was the frontline choice for patients with severe AA aged ≤40 years, while HID-HSCT was as effective as IST for patients without an MSD.

Leptin-mediated proinflammatory bone marrow environment in acquired aplastic anemia.

Acquired aplastic anemia (AA), a paradigm of bone marrow failure syndrome, is mainly caused by abnormal immune activation. The enhanced adipogenesis of bone marrow-derived mesenchymal stem cell (BM-MSC) results in a fatty marrow of AA. Leptin, an adipokine mainly generated by adipocytes, has powerful proinflammatory effects on immune cells and is associated with various autoimmune diseases. However, the role of leptin in the hyperimmune status of AA remains unknown. In this study, we firstly discovered the higher leptin concentration in AA-BM than that in healthy donors (HD)-BM and myelodysplastic syndrome (MDS)-BM. Then, we found AA-MSC could express high amounts of leptin during the process of adipogenesis. Compared with HD, the leptin receptor was also highly expressed on T cells in AA-BM. Furthermore, leptin significantly accelerated the proliferation and activation of T cells in AA-BM. And, leptin promoted the production of interferon-γby T cells in AA-BM. However, leptin remarkably inhibited the conversion of CD4+CD25- T cells into CD4+Foxp3+ T cells. Finally, we detected the cell signaling pathway in T cells from AA patients and found leptin could activate the STAT3 pathway. In summary, our data revealed the high expression of adipokine leptin in AA-BM which shaped a proinflammatory environment for T cells in AA-BM by activating the JAK2/STAT3 pathway.

Platelet/Lymphocyte ratio independently predicts the outcome of severe aplastic anemia patients treated with antithymocyte globulin.

OBJECTIVE: The aim of this study was to determine the clinical role of platelet/lymphocyte ratio and neutrophil/lymphocyte ratio in severe aplastic anemia patients treated with antithymocyte globulin. METHODS: The outcomes of consecutive severe aplastic anemia patients treated with rabbit or swine antithymocyte globulin plus cyclosporine (n=159, from January 2012 to December 2018) were analyzed retrospectively. RESULTS: In a total of 159 patients, the actuarial 5-year survival rate was 85.6%. Low platelet/lymphocyte ratio (PLR≤55) was significantly associated with less complications at 1 month and 24 months after the antithymocyte globulin treatment (p=0.048 and 0.028, respectively). The univariate and multivariate analyses revealed that low platelet/lymphocyte ratio was an independent predictor of overall survival (p=0.03 and 0.04, respectively). Patients with low neutrophil/lymphocyte ratio (NLR≤0.18) had shorter survival time, but there was no significant difference (p=0.056). PLR was positively correlated with neutrophil/lymphocyte ratio (r=0.38, p<0.0001) and age (r=0.17, p=0.0379), while it was negatively correlated with IgG level (r=-0.18, p=0.0309). The ratio of CD4/CD8 was significantly higher in low platelet/lymphocyte ratio group (p=0.005). CONCLUSION: The platelet/lymphocyte ratio reflects the immune abnormality of SAA. Notably, low platelet/lymphocyte ratio is an independently positive prognostic factor for severe aplastic anemia patients treated with antithymocyte globulin.

A hemizygous p.R204Q mutation in the ALAS2 gene underlies X-linked sideroblastic anemia in an adult Chinese Han man.

BACKGROUND: X-linked sideroblastic anemia (XLSA) is the most common form of congenital sideroblastic anemia (CSA), and is associated with the mutations in the 5-aminolevulinate synthase 2 (ALAS2). The genetic basis of more than 40% of CSA cases remains unknown. METHODS: A two-generation Chinese family with XLSA was studied by next-generation sequencing to identify the underlying CSA-related mutations. RESULTS: In the study, we identified a missense ALAS2 R204Q mutation in a hemizygous Chinese Han man and in his heterozygous daughter. The male proband presented clinical manifestations at 38 years old and had a good response to pyridoxine. CONCLUSIONS: XLSA, as a hereditary disease, can present clinical manifestations later in lives, for adult male patients with ringed sideroblasts and hypochromic anemia, it should be evaluated with gene analyses to exclude CSA.

Small PNH clones detected by fluorescent aerolysin predict a faster response to immunosuppressive therapy in patients with severe aplastic anaemia.

Objectives: To clear the obscure conclusion on the prediction value of paroxysmal nocturnal haemoglobinuria (PNH) clones in severe aplastic anaemia (SAA) patients treated with immunosuppressive therapy (IST). Methods: We retrospectively analyzed 219 consecutive SAA patients treated with IST from October 2008 to October 2015 and evaluated the haematological responses to IST. Results: The presence of a PNH clone was detected in 55 (25.1%) patients prior to IST [37/88 by flow cytometry (FCM) and 18/131 by fluorescent aerolysin (FLAER)] and 27 disappeared after IST (23/37 in initial FCM group, 4/18 in initial FLAER group, p = 0.005). In patients without an initial clone, 12 (30.0%) cases in FCM and 17 (19.5%) in FLAER groups presented a PNH clone at least once after IST (p < 0.001). In patients with a pre-treatment PNH clone detected by FCM, the 3-, 6- and 12-month response rates were higher than patients without (p = 0.006; 0.002 and 0.002, respectively). And in FLAER group, the 3-month response rate was significantly higher in those with a prior clone (p = 0.017), however, the 6- and 12-month response rates showed no differences (p = 0.105, p = 0.144, respectively). By multivariate analysis, a shorter interval between diagnosis and treatment is associated with a better response and survival. Conclusions: A more reliable FLAER method allows us to draw a conclusion that PNH clone predicts a faster response but not a higher response rate to IST. Once a diagnosis is confirmed, the IST should be initiated as soon as possible.

Long-term follow-up of a novel immunosuppressive strategy of cyclosporine alternatively combined with levamisole for severe aplastic anemia.

Hematopoietic stem cell transplantation (HSCT) and immunosuppressive therapy (IST) with antithymocyte globulin (ATG) and cyclosporine (CsA) have been widely accepted as the standard first-line treatments for severe aplastic anemia (SAA). However, most of the patients with SAA had a slim chance to access these strategies in developing countries. Here, we reported 10-year results in a cohort of 232 patients with SAA who received a novel IST of CsA, levamisole, and danazol (CsA&LMS-based regimen). The cumulative incidence of response was 52.1% at 6 months, 66.4% at 12 months, and 77.1% at 24 months. The 10-year overall survival (OS) and failure-free survival was 60.2% and 48.3%, respectively. Positive predictors of OS in multivariate analysis were higher pretreatment ANC, younger age, higher pretreatment absolute reticulocyte count (ARC), and response within 6 months. The probability of CsA&LMS discontinuation was 50.2% at 10 years. With a slow CsA&LMS taper, the actuarial risk for relapse was only 9.5%. The cumulative incidence of MDS/AML was 8.2% at 10 years. The long-term follow-up information demonstrated that the CsA&LMS regimen could be a promising strategy for patients with SAA in developing countries.

[MiR-335-5p-Mediated Dysfunction of T Lymphocytes in Patients with Acquired Aplastic Anemia].

OBJECTIVE: To explore the effect of miR-335-5p/ADCY3 interaction on the lymphocyte function in the patients with aplastic anemia (AA). METHODS: Blood samples were collected from 22 healthy volunteers (HC) and 50 AA patients including 38 severe AA (SAA) and 12 non-severe AA (NSAA). Peripheral blood mononuclear cells (PBMNC) were isolated. The expression of miR-335-5p and ADCY3 mRNA was detected by using RT-PCR. Negative control miR-335-5p (NC group) and miR-335-5p mimic (mimic group) were transfected to AA-PBMNC by using RNAimax reagent, respectively. The proliferative ability, activation and cytokines of CD4+ T and CD8+ T cells were measured by flow cytometry. Dual-luciferase reporter assay was used to verify the targeted relationship between miR-335-5p and target gene. RESULTS: The expression of miR-335-5p was significantly downregulated in SAA-PBMNC and NSAA-PBMNC compared with HC-PBMNC (0.08±0.01 vs 0.74±0.10, P＜0.01; 0.17±0.02 vs 0.74±0.10, P＜0.01). Meanwhile, the expression of miR-335-5p in SAA-PBMNC was very statistically significantly lower than that in NSAA-PBMNC (P＜0.01). Compared with NC group, upregulation of miR-335-5p in vitro could significantly inhibited the proliferation of CD4+ T and CD8+ T cells in AA-PBMNC (P＜0.05 and P＜0.05, respectively). And, upregulating miR-335-5p in AA-PBMNC could significantly inhibited the activation of CD4+ and CD8+ T cells (P＜0.01 and P＜0.01, respectively). The ratio of CD4+TNFα+ T, CD8+IFNγ++T and CD8+TNFα+ T cell by up-regulating the expression of miR-335-5p from AA-PBMNC in vitro was also significantly lower (P＜0.01, P＜0.05 and P＜0.05, respectively). In addition, the expression of ADCY3 was higher in AA-PBMNC than that in HC-PBMNC (1.70±0.15 vs 0.76±0.12, P＜0.01). Furthermore, by means of dual-luciferase reporter assay, the luciferase activity of ADCY3'UTR wildtype could be inhibited by miR-335-5p. CONCLUSIONS: The expression of miR-335-5p was significantly downregulated in AA, and that correlates with disease severity. Up-regulating miR-335-5p can correct the hyperimmune status in AA patients by targeting ADCY3. These changes may relates with the strengthen of inhibition for targeted gene ADCY3.

Human Supernumerary Teeth-Derived Apical Papillary Stem Cells Possess Preferable Characteristics and Efficacy on Hepatic Fibrosis in Mice.

Dental tissue has been acknowledged as an advantaged source for high-quality dental pulp stem cell (DPSC) preparation. However, despite the accomplishment of the separation of DPSCs from permanent teeth and supernumerary teeth, the deficiency of rigorous and systematic clarification on the signatures and efficacy will hinder their prospects in regenerative medicine. In this study, we primitively isolated permanent teeth-derived DPSCs and supernumerary teeth-derived apical papillary stem cells (SCAP-Ss) with parental consent. Immunophenotype of DPSCs and SCAP-Ss was determined by a flow cytometry assay, and the cell viability was verified by multidimensional detections including cell proliferation, cell cycle, apoptosis, and senescence. The migration and clonogenic capacity were examined by a wound healing test and crystal violet staining, respectively. The multilineage differentiation potential was quantitated by utilizing Oil Red O staining and Alizarin Red staining, together with real-time PCR analysis. The efficacy on a mouse hepatic fibrosis model was evaluated by using histologic sections and liver function tests. Herein, we showed that SCAP-Ss exhibited comparable immunophenotype and adipogenic differentiation capacity as DPSCs. However, different from DPSCs, SCAP-Ss exhibited superiority in cell viability and osteogenic differentiation. Simultaneously, injection of DPSCs and SCAP-Ss significantly reduced inflammatory infiltration, enhanced liver-associated gene expression, and finally relieved symptoms of hepatic fibrosis. In conclusion, SCAP-Ss possess preferable characteristics and efficacy on hepatic fibrosis in mice. Our findings suggest that SCAP-Ss are an easily accessible postnatal stem cell source with multifaceted characteristics for regenerative medicine.

Multifaceted characterization of the signatures and efficacy of mesenchymal stem/stromal cells in acquired aplastic anemia.

BACKGROUND: Longitudinal studies have verified the pivotal role of mesenchymal stem/stromal cells (MSCs) in the bone marrow microenvironment for hematopoiesis and coordinate contribution to leukemia pathogenesis. However, the precise characteristics and alternation of MSCs during acquired aplastic anemia (AA) remain obscure. METHODS: In this study, we originally collected samples from both healthy donors (HD) and AA patients to dissect the hematological changes. To systematically evaluate the biological defects of AA-derived MSCs (AA-MSCs), we analyzed alterations in cellular morphology, immunophenotype, multi-lineage differentiation, cell migration, cellular apoptosis, and chromosome karyocyte, together with the immunosuppressive effect on the activation and differentiation of lymphocytes. With the aid of whole genome sequencing and bioinformatic analysis, we try to compare the differences between AA-MSCs and HD-derived MSCs (HD-MSCs) upon the molecular genetics, especially the immune-associated gene expression pattern. In addition, the efficacy of umbilical cord-derived MSC (UC-MSC) transplantation on AA mice was evaluated by utilizing survivorship curve, histologic sections, and blood cell analyses. RESULTS: In coincidence with the current reports, AA patients showed abnormal subsets of lymphocytes and higher contents of proinflammatory cytokines. Although with similar immunophenotype and chromosome karyotype to HD-MSCs, AA-MSCs showed distinguishable morphology and multiple distinct characteristics including genetic properties. In addition, the immunosuppressive effect on lymphocytes was significantly impaired in AA-MSCs. What is more, the cardinal symptoms of AA mice were largely rescued by systemic transplantation of UC-MSCs. CONCLUSIONS: Herein, we systematically investigated the signatures and efficacy of MSCs to dissect the alterations occurred in AA both at the cellular and molecular levels. Different from HD-MSCs, AA-MSCs exhibited multifaceted defects in biological characteristics and alterative molecular genetics in the whole genome. Our findings have provided systematic and overwhelming new evidence for the defects of AA-MSCs, together with effectiveness assessments of UC-MSCs on AA as well.

Systematic comparison of hUC-MSCs at various passages reveals the variations of signatures and therapeutic effect on acute graft-versus-host disease.

BACKGROUND: Mesenchymal stem cells are heterogenous populations with hematopoietic supporting and immunomodulating capacities. Enormous studies have focused on their preclinical or clinical therapeutic effects, yet the systematic study of continuous in vitro passages on signatures and functions of UC-MSCs at both the cellular and molecular levels is still lacking. METHODS: In this study, to systematically evaluate the biological properties of MSCs at various passages, we analyzed biomarker expression, cell proliferation and apoptosis, chromosome karyotype, and tri-lineage differentiation potential. Subsequently, we took advantage of whole-exome sequencing to compare the somatic hypermutation of hUC-MSCs at P3, P6, and P15 including SNV and INDEL mutations. In addition, to explore the safety of the abovementioned hUC-MSCs, we performed metabolic pathway enrichment analysis and in vivo transplantation analysis. Furthermore, we cocultured the abovementioned hUC-MSCs with UCB-CD34+ HSCs to evaluate their hematopoietic supporting capacity in vitro. Finally, we transplanted the cells into acute graft-versus-host disease (aGVHD) mice to further evaluate their therapeutic effect in vivo. RESULTS: The hUC-MSCs at P3, P6, and P15 showed similar morphology, biomarker expression, and cytokine secretion. hUC-MSCs at P15 had advantages on adipogenic differentiation and some cytokine secretion such as IL-6 and VEGF, with disadvantages on cell proliferation, apoptosis, and osteogenic and chondrogenic differentiation potential. Based on the SNP data of 334,378 exons and bioinformatic analyses, we found the somatic point mutations could be divided into 96 subsets and formed 30 kinds of signatures but did not show correlation with risk of tumorigenesis, which was confirmed by the in vivo transplantation experiments. However, hUC-MSCs at P15 showed impaired hematologic supporting effect in vitro and declined therapeutic effect on aGVHD in vivo. CONCLUSIONS: In this study, we systematically evaluated the biological and genetic properties of hUC-MSCs at various passages. Our findings have provided new references for safety and effectiveness assessments, which will provide overwhelming evidence for the safety of hUC-MSCs after continuous in vitro passages both at the cellular and molecular levels for the first time. Taken together, our studies could help understand the controversial effects of disease treatment and benefit the clinical research of UC-MSCs.

JNKi- and DAC-programmed mesenchymal stem/stromal cells from hESCs facilitate hematopoiesis and alleviate hind limb ischemia.

BACKGROUND: Mesenchymal stem/stromal cells (MSCs) derived from human embryonic stem cells (hESCs) are attractive for their hematopoietic-supporting or potential therapeutic effects. However, procedures for high-effective and scalable generation of MSCs from hESCs within 2 weeks are still unestablished, which also hinder the development and mechanism study of mesengenesis. METHODS: In this study, we aimed to establish a strategy for programming hESC differentiation into MSCs by practicing small-scale chemical compound screening. Then, we used flow cytometry, multi-lineage differentiation, and karyotype analyses to investigate the biological phenotypes of the derived hESC-MSCs. Also, to explore whether the derived cells had hematopoietic-supporting ability in vitro, we carried out the cobblestone formation and megakaryocytic differentiation experiments. To further evaluate the function of hESC-MSCs in vivo, we transplanted the cells into a mouse model with hind limb ischemia. RESULTS: By simultaneous treatments with a JAK/STAT antagonist and a DNA methylation inhibitor, the efficiency of generating hESCs into CD73+ hESC-MPCs could reach 60% within 7 days. The derived cells further matured into hESC-MSCs, with comparable characteristics to those of adult MSCs in terms of surface markers, normal karyotype, and the potential for adipogenic, osteogenic, and chondrogenic differentiation. Functionally, hESC-MSCs had hematopoietic-supporting effects in vitro and could notably relieve symptoms of hind limb ischemia. CONCLUSIONS: In the study, we established a high-efficient procedure for large-scale generation of MSCs from hESCs, which would be of great help for genesis and mechanism studies of MSCs. Meanwhile, the derived cells provide an alternative for translational clinical research.