To investigate the relationship between CD4(+)CD25(+)CD127(dim) regulatory T cells (Tregs) and immune imbalance in acquired severe aplastic anemia (SAA).

Myelodysplastic syndromes (MDS) are clonal stem cell disorders characterized by ineffective hematopoiesis that lead to leukemia. Disorders of the immune system serve important functions in the pathophysiology and progression of this disease. Different levels or mechanisms of natural killer (NK) cells in patients with MDS have been measured in previous studies, making it challenging to understand the pathogenesis of NK cytotoxicity. The present study investigated the frequency of NK cell-mediated antibody-dependent cellular cytotoxicity and explored the function of NK cells by their activating receptors, inhibition signals, degranulation and cytotoxicity factors. In the present study, levels of cluster of differentiation (CD)3-CD56+ NK cells, CD16+-expressing NK cells and subset CD56dim NK cells were decreased in the peripheral blood of patients with MDS. Altered expression of NK protein 44, NK group 2 member D, killer cell immunoglobulin-like receptor 2DL1 (KIR2DL1) and KIR2DL3 on NK cell effector signaling pathways may trigger tumor cell lysis in patients with MDS. The weak cellular adhesion and decreased cytotoxicity of NK cells may lead to ineffective antitumor activity in MDS. These observations suggested that NK cells may serve as immunological determinants in MDS and may permit the development of NK cell-based immunotherapy for the treatment of patients with MDS.

Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal stem cell disorders characterized by cytopenia and dysplasia. Anemia is the most common symptom in patients with MDS. Mitophagy and mitochondrial dysfunction might be involved in the development of MDS. In this study, we investigated the change of mitophagy in erythroid precursors in MDS patients. We found that NIX-mediated mitophagy was impaired in bone marrow nucleated red blood cells (NRBC) of MDS patients, associated with an increased amount of damaged mitochondria and increased ROS level which might lead to apoptosis and ineffective erythropoiesis. The results showed that the amount of mitochondria in GlycoA+ NRBC positively correlated with the count of ring sideroblasts in bone marrow samples. Meanwhile, the level of autophagy-associated marker LC3B in GlycoA+ NRBC had a positive correlation with hemoglobin (Hb) levels, and the amount of mitochondria in GlycoA+ NRBC had a negative correlation with Hb levels in high-risk MDS patients. Our results indicated that mitophagy might involve the pathogenesis of anemia associated with MDS. Autophagy might be a novel target in treatments of MDS patients.

Severe aplastic anemia (SAA) is an autoimmune disease in which bone marrow failure is mediated by activated myeloid dendritic cells (mDCs) and T lymphocytes. Recent research has identified a strong immunomodulatory effect of pyruvate kinase M2 (PKM2) on dendritic cells in immune-mediated diseases. In this study, we aimed to explore the role of PKM2 in the activation of mDCs in SAA. We observed conspicuously higher levels of PKM2 in mDCs from SAA patients compared to normal controls at both the gene and protein levels. Concurrently, we unexpectedly discovered that after the mDC-specific downregulation of PKM2, mDCs from patients with SAA exhibited weakened phagocytic activity and significantly decreased and shortened dendrites relative to their counterparts from normal controls. The expression levels of the costimulatory molecules CD86 and CD80 were also reduced on mDCs. Our results also suggested that PKM2 knockdown in mDCs reduced the abilities of these cells to promote the activation of CD8+ T cells (CTLs), leading to the decreased secretion of cytotoxic factors by the latter cell type. These findings demonstrate that mDC activation requires an elevated intrinsic PKM2 level and that PKM2 improves the immune status of patients with SAA by enhancing the functions of mDCs and, consequently, CTLs.

Cofilin-1 interacts with actin to regulate cell movement. The importance of cofilin-1 in immunity has been established, and its involvement in a number of autoimmune diseases has been confirmed. However, its role in severe aplastic anaemia (SAA) remains elusive. Thus, the aim of the current study was to investigate the role of cofilin-1 in patients with SAA. Flow cytometry, Western blotting and real-time quantitative reverse transcription-polymerase chain reaction were performed to detect the mRNA and protein expression of cofilin-1 in myeloid dendritic cells (mDCs) from patients with SAA. The expression of cofilin-1 was then suppressed via siRNA, and its effects on mDCs and downstream effector T-cell function were evaluated. Cofilin-1 expression was higher in mDCs from patients with SAA and correlated with routine blood and immune indexes. Moreover, cofilin-1 knockdown in mDCs from patients with SAA reduced their phagocytic capacity, migration capacity, and CD86 expression through F-actin remodelling, downregulating the stimulatory capacity of mDCs on CD4+ and CD8+ T lymphocytes. Collectively, these findings indicate that cofilin-1 participates in the hyperfunction of mDCs in patients with SAA and that the downregulation of cofilin-1 in mDCs from patients with SAA could be a novel treatment approach for SAA.

To explore the effect of IL-6 on the activity and secretory function of B cells and analyze its effect on clinical indicators and efficacy in wAIHA patients. This study included 25 hemolytic wAIHA patients, 13 remission patients, and 10 HCs. Plasma levels of various cytokines were detected using CBA. PBMCs were extracted from 12 hemolytic wAIHA patients and divided into three wells, stimulation with IL-6 and IL-6 + tocilizumab, the blank control wells were also set. After 48 h of in vitro cell culture, percentage of CD5+CD80+, CD5-CD80+,CD5+CD86+,CD5-CD86+,CD5+IL-10+,CD5-IL-10+B cells were determined by flow-cytometry. Plasma levels of IL-6 and IL-10 in hemolytic episode group were significantly higher than that in HCs group (p = 0.0243; p = 0.0214). RBC and Hb levels were negatively correlated with IL-6 levels in wAIHA patients, while LDH levels were positively correlated.Therapeutic effects of glucocorticoid and duration of efficacy were also significantly correlated with IL-6 levels in wAIHA patients. After 48 h in vitro cell culture, percentages of CD80+/CD5+CD19+and CD80+/CD5-CD19+ cells in the IL-6 stimulation group were higher than those in blank control group (p = 0.0019; p = 0.0004), while CD86+/CD5+ CD19+ and CD86+/CD5-CD19+ cells were not statistically different before and after IL-6 stimulation. Percentage of IL-10+/CD5+ CD19+ cells in IL-6 stimulation group was lower than that in blank control (p = 0.0017) and IL-6 + toc (p = 0.0117) group. Percentage of IL-10+/CD5- CD19+cells in the IL-6 stimulation group was lower than that in the blank control group (p = 0.0223). Plasma levels of IL-6 were significantly elevated in hemolytic wAIHA patients and correlated with clinical indicators and efficacy. IL-6 promotes the activation of B cells. Although the results were not statistically significant, IL-6R antagonist tocilizumab may hopefully become a targeted therapy for wAIHA patients.

T cell immunoglobulin and mucin domain 3(TIM3) is a negative regulator of cellular immunity and it is highly expressed on CD8+T cells in persistent viral infection and cancer setting as report. However, how TIM3 expressed on CD8+T cells in myelodysplastic syndrome (MDS), that is a malignant disorder, has not been clarified. Here, decreased CD8+T cells, less IFN-γ secretion in CD8+T cells and increased TIM3 on CD8+T cells had been seen. Increased TIM3+CD8+T cells with lower perforin and granzyme B expression and higher CD95 expression in MDS patients had been observed. These findings suggested that TIM3 might be related to CD8+T cells defect. Therefore, further explorations about mechanism of TIM3+CD8+T cells defect are needed, which might be helpful for adoptive T-cell therapy in MDS.

Severe aplastic anemia (SAA) is a rare and potentially life-threatening disease characterized by pancytopenia and bone marrow (BM) hypoplasia. In a previous study by our group, increased expression of leukocyte immunoglobulin-like receptors A (LILRA), LILRA3 in myeloid dendritic cells (mDCs) and LILRA5 in CD34+ cells in SAA was detected using proteomics techniques, highlighting their potential role in disease pathogenesis. In the present study, the expression of LILRA1-6 mRNA was assessed in the BM mononuclear cells of patients with SAA using reverse transcription-quantitative (RT-q)PCR. The expression of homogenic LILRA3 and LILRA5 isoform on mDCs, as well as CD34+, CD3+CD8+, CD19+ and CD14+ cells, was detected using flow cytometry. mDCs were then induced, cultured and sorted. The expression of LILRA3 was confirmed using RT-qPCR and western blot analyses. The serum levels of soluble LILRA3 were measured using ELISA. Furthermore, the relationship between LILRA3 expression and disease severity was assessed. The results indicated increased LILRA3 mRNA expression in patients with SAA. The percentage of LILRA3+ in BM mDCs and CD34+ cells was increased. Compared with controls, the relative LILRA3 mRNA expression and the relative protein intensity were highly increased in SAA mDCs. The serum LILRA3 levels in patients with SAA were also increased. The proportion of LILRA3+CD11C+ human leukocyte antigen (HLA)-DR+/CD11C+HLA-DR+ cells was positively correlated with the ratio of LILRA3+CD34+/CD34+ cells and the expression of LILRA3 mRNA. Taken together, the expression of LILRA3 on mDCs of patients with SAA was increased, which may affect the function of mDCs. LILRA3 may have a significant role in the immune pathogenesis of SAA.

Immuno-related pancytopenia (IRP) is characterized by pancytopenia resulting from bone marrow suppression or destruction mediated by auto‑antibodies. In our previous study, a K562 cDNA library was established, which was used to screen for seven possible auto‑antigens produced by hematopoietic cells in patients with IRP, including ferritin light chain (FTL). In the present study, FTL was expressed and purified, and the levels of the auto‑antibodies specific to FTL were measured. Through ELISA, it was shown that the titer of anti‑FTL antibodies was higher in patients with IRP without treatment compared with those who had recovered from IRP, those with severe aplastic anemia (SAA), those with myelodysplastic syndrome (MDS) and the healthy controls. Furthermore, the expression levels of FTL‑mRNA were upregulated in patients with IRP without treatment compared with those who had recovered from IRP, those with MDS and the normal controls. The results suggest that FTL antibody expression is upregulated in patients with IRP. Detecting FTL antibodies may therefore have certain clinical value in differentiating between IRP, SAA and MDS. Furthermore, in specific patients with IRP, FTL as an auto‑antigen may induce immune attack on hematopoietic stem cells.

Immune abnormalities play an important role in the pathogenesis and progression of myelodysplastic syndrome (MDS). Some patients with MDS have autoimmune diseases (AI). Follicular helper T (Tfh) cells help B cells produce antibodies. The role of Tfh in MDS with AI has not been studied.

Background. The myelodysplastic syndrome (MDS) comprises a group of clonal hematopoietic stem cell diseases characterized by cytopenia, dysplasia in one or more of the major myeloid lineages, ineffective hematopoiesis, and increased risk of development of acute myeloid leukemia (AML). Macrophages are innate immune cells that ingest and degrade abnormal cells, debris, and foreign material and orchestrate inflammatory processes. We analyzed the role of macrophages from MDS patients in vitro. Methods. Macrophages were induced from peripheral blood of patients with MDS via granulocyte macrophage colony-stimulating factor (GM-CSF). Phagocytic capacity of macrophages was measured with carboxyfluorescein succinimidyl ester and fluorescent microspheres. CD206 and signal regulatory protein alpha (SIRPα) on macrophages were detected by flow cytometry. Inducible nitric oxide synthase (iNOS) was measured by ELISA method. Results. Compared with normal control group, the number of monocytes increased in MDS patients. However, the monocytes showed impaired ability to induce macrophages and the number of macrophages induced from MDS samples was lower. Further, we demonstrated that the ex vivo phagocytic function of macrophages from MDS patients was impaired and levels of reorganization receptors CD206 and SIRPα were lower. Levels of iNOS secreted by macrophages in MDS were increased. Conclusions. Monocyte-derived macrophages are impaired in myelodysplastic syndromes.

Autoimmune haemolytic anaemia (AIHA) is a kind of autoimmune diseases characterized by autoantibodies which produced and secreted by abnormal activated B lymphocytes directed against red blood cells (RBC). Study reveals that about 50% AIHA mainly occurs secondary to lymphoproliferative disorders (LPD) and autoimmune diseases. In this study, we aim to explore the characteristics of patients with AIHA secondary to LPD. Fifteen patients with AIHA secondary to LPD (secondary group) and 60 with primary AIHA (primary group) were retrospectively included. Patients in the secondary group [(59.40 ± 4.74) y] were older than those in the primary group [(47.53 ± 2.30) y] (p = 0.024). Reticulocyte counts were lower for the secondary group [(134.55 ± 20.67) × 109/L] than for the primary group [(193.88 ± 27.32) × 109/L] (p = 0.09). Haptoglobin was higher in the secondary (0.75 ± 0.19) g/L than in the primary group (0.34 ± 0.05) g/L (p = 0.004). The ratio of CD3+CD4+/CD3+CD8+ was higher in the secondary (1.81 ± 0.41) than in the primary (1.05 ± 0.12) group (p = 0.025). Duration of remission was shorter in the secondary [(23.52 ± 5.20) months] than in the primary [(40.87 ± 3.92) months] group (p = 0.013). Relapse rate was higher for the secondary (33.3%) than for the primary (8.3%) group (p = 0.003). Mortality rate was higher in the secondary (33.3%) than in the primary (8.3%) group (p = 0.003). Progression-free survival was shorter in the secondary than in the primary group (p = 0.021). In conclusion, patients with AIHA secondary to LPD showed higher age at diagnosis, shorter remission time, and higher recurrence and mortality rates than did those with primary AIHA.

Autoimmune hemolytic anemia (AIHA) is rare heterogeneous disorder characterized by red blood cell (RBC) destruction via auto-antibodies, and after RBC is destroyed, proinflammatory danger-associated molecular patterns including extracellular hemoglobin, heme, and iron which causing cell injury. And oxidative stress represents one of the most significant effects of chronic hemolysis. Jianpishengxue keli can improve the symptoms of anemia patients with kidney disease and tumors and are beneficial in promoting recovery from chronic inflammation. Therefore, it is presumed that Jianpishengxue keli can improve the symptoms of AIHA. We aimed to investigate iron metabolism in AIHA and effects of Jianpishengxue keli on AIHA murine model.

We aimed to investigate the balance between the mRNA levels of histone acetyltransferases (HATs) and histone deacetylases (HDACs) in CD8+ T cells of patients with severe aplastic anemia (SAA).

A deeper understanding of the pathogenesis of severe aplastic anemia (SAA) is urgently warranted to achieve better therapeutic effects. The objective of this study was to investigate the phagocytosis of myeloid dendritic cell (mDC) in SAA patients.

Hepatitis-associated aplastic anemia (HAAA) is a variant of severe aplastic anemia (SAA) in which bone marrow failure follows an acute attack of hepatitis. Its pathogenesis is poorly understood. We investigated the prevalence of HAAA among cases of newly diagnosed SAA presenting to our hospital between January 1998 and February 2013, and analyzed the clinical and immune characteristics of HAAA and non-hepatitis-associated SAA (non-HASAA) patients. The prevalence of HAAA among cases of SAA was 3.8% (36/949), and the majority of patients (33/36) were seronegative for a known hepatitis virus. Compared with non-HASAA patients, HAAA patients had a larger proportion of CD8+ T cells, a lower ratio of CD4+/CD8+ T cells, and a smaller proportion of CD4+CD25+ regulatory T cells. There was no significant difference in peripheral blood count, bone marrow cellularity, or the number of blood transfusions received between HAAA and non-HASAA patients. HAAA patients had a higher early infection rate and more infection-related mortality in the first 2 years after diagnosis than non-HASAA patients, and their 2-year survival rate was lower. The results demonstrate that HAAA patients have a more severe T cell imbalance and a poorer prognosis than non-HASAA patients.

Myelodysplastic syndromes (MDS) are a group of clonal hematopoietic diseases which have a high risk of progressing to acute myeloid leukemia. MDS patients have immunologic deficiency, including T and B cells dysfunction. Follicular T helper cells (Tfh, CD4+CXCR5+) are an important subset of helper T cells which help to the formation of germinal centers and B cells differentiation. In this study, we investigated the proportion and function of Tfh using NUP98-HOXD13 transgenic (NHD13) mice model with MDS phenotype. The proportion of Tfh from bone marrow and spleen of NHD13 mice decreased compared with wild type (WT) mice tested by flow cytometry. In NHD13 mice spleens, there were decreased CXCR5+ cells and increased PD-1+ cells using immunohistochemistry. The active markers (ICOS, CD40L and OX40) expressed on Tfh of NHD13 mice were decreased. In contrast, PD-1 expression on Tfh of NHD13 mice was higher than that of WT mice. After coculture with Tfh from NHD13 mice, IgG and IgM production of B cells were decreased. In conclusion, the proportion and function of Tfh in the MDS mice model were altered. The dysfunction and reduction of Tfh may inhibit B cells differentiation and antibody production. Abnormal Tfh might contribute to the immune tolerance promoting the progression of MDS.

Myelodysplastic syndromes (MDSs) are a group of heterogeneous hematopoietic stem/progenitor cells clonal diseases, characteristic features with myeloid dysplasia, leading to abnormality of neutrophils. Recent studied have showed that neutrophils act not only as professional killers, but also as regulators of innate and adaptive immune in infection and inflammatory condition. The CD54highCD181low neutrophils are a kind of reverse-transmigrated neutrophils characterized proinflammatory phenotype. We investigated the frequency and functional properties of circulating CD54highCD181low neutrophils in patients with untreated MDS. Frequency of CD54highCD181low neutrophils was significantly increased in MDS patients and related to the severity of the disease. Furthermore, CD54highCD181low neutrophils suppressed CD8+ T cells functions in vitro. CD54highCD181low neutrophils lead to upregulation of PD1 on CD8+ T cells. Higher CD54highCD181low neutrophils were related to poor prognosis and more infections. The frequency of CD54highCD181low neutrophils decreased in high risk MDS patients who had response after treatment with decitabine. Overall, we identified CD54highCD181low neutrophils expanded in MDS. The exact mechanisms of increased CD54highCD181low neutrophils and its effect on immune function remain to be elucidated.

This study is aimed at assessing the subsets of bone marrow macrophages in patients with myelodysplastic syndrome (MDS) and exploring the role of macrophages in the pathogenesis of MDS.

Severe aplastic anemia (SAA) is a syndrome of severe bone marrow failure with high mortality. Our previous studies have demonstrated that both immature and activated DC1 increased in the bone marrow of SAA patients, and the balance of DC1 subsets shifted the stable form to active one, which might promote Th0 cells to polarize to Th1 cells and cause the over-function of T lymphocytes and hematopoiesis failure in SAA. So we assumed myeloid dendritic cells (mDCs) may be the key immune cells that cause destruction of hematopoietic cells in SAA, but the mechanism of activation of mDCs is unclear. Here, we investigated the proteome of mDCs in SAA patients to further explore the pathogenesis of SAA and the possible antigen that leads to immune activation in SAA. mDCs from 12 SAA patients, 12 remission patients and 12 controls were sorted by flow cytometry and examined by two-dimensional gel electrophoresis and mass spectrometry. Intensity changes of 41 spots were detected with statistical significance. Nine of the 41 spots were identified by MALDI-TOF/TOF tandem mass spectrometry. Changes in protein expression levels were found in the SAA group. These changes reveal that abnormal expression of cofilin, glucose-6-phosphate dehydrogenase and pyruvate kinase enzyme M2 in mDCs from SAA patients may be the reason for mDC hyperfunction.