Convalescent plasma (CP) has been applied to the treatment of many virus infectious diseases. This paper summarized the previous researches in contagious viral diseases treated with CP, and analyzed CP therapy as a potential treatment for COVID-19. We summarized the technical progress of CP in recruitment, plasma treatment, antibody titer detection, and its clinical treatment experiences in avian influenza virus, MERS-CoV, SARS-CoV, EBOV, SARS-CoV-2 and other viral infections, and adverse events related to plasma transfusion. Some case reports on CP therapies and retrospective analysis suggest that CP can reduce case fatality rate (CFR), so it can be used as a potential treatment for COVID-19.

Objective To analyze the novel coronavirus pneumonia convalescents' health status and antibody levels, and select suitable donors for convalescent plasma collection and treatment. Methods The relevant medical examination data of discharged patients diagnosed with novel coronavirus pneumonia in the First Hospital of Changsha from February 7 to March 8, 2020, and health status of those who were willing to participate in convalescent plasma donation were evaluated. ELISA was used to detect novel coronavirus IgM, IgG antibody and total antibody, solid phase red cell adherence assay was used to screen platelet antibody, agglutination was used to detect and irregular red cell antibodies. Results The average age of 15 donors was 32 years old, the average length of hospital stay was 16.5 days, and the average sample collection time was 17.9 days before discharge. 2019-nCoV RNA screening results of 15 donors were all negative and 1 HBsAg positive was not qualified for donation. All 15 donors were negative for direct antibody and irregular antibody screening, and nonspecific positive for platelet antibody screening. 20% (3/15) was IgM negative, 53.33% (8/15) IgG antibody titer was greater than 160, 60% (9/15) total antibody titer was greater than 320, 46.67% (7/15) met both IgG antibody titer greater than 160 and total antibody titer greater than 320. Conclusion 46.67%~60% of proposed donors was permitted to donate convalescent plasma. It is of great significance to conduct the novel coronavirus pneumonia convalescents' health assessment and antibody level screening before collection, in order to select suitable donors and ensure the convalescent plasma treatment effect.

Novel coronavirus pneumonia (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2（SARS-CoV-2） has spurred a global health crisis. To date, there is no effective therapy for COVID-19 patients. Convalescent plasma from recovered infection patient contains neutralizing antibodies against the same infection. Transfusion convalescent plasma to infected patients is a form of passive antibody therapy, can be traced back as early as the 20th century. The CP has been used in outbreaks of other respiratory infections. Available evidence from use of convalescent plasma in SARS-CoV-1 and MERS patients suggested that CP was safe. Blood establishment should develop COVID-19 CP workflow according to national and local guidelines, to illustrate the individual steps that need to be undertaken, including assessment of CP donor eligibility, informed consent, recruitment, pre-donation screening, antibody testing, collections, processing, virus testing, storage, distribution, transfusion of CP and assessment of efficacy, in order to maximize safety of CP donors and recipients. At the same time, we also need to pay attention to the potential risks of CP transfusion, including：antibody-mediated enhancement(ADE), allergic transfusion reactions, febrile reactions, transfusion-related acute lung injury (TRALI), transfusion-associated cardiac overload (TACO). In a complex nursing environment with a large number of confounding factors, Randomized Controlled Trial（RCT） is the most effective and efficient strategy to determine the efficacy and safety of COVID-19 CP clinical therapy.

Objective By analysis on characteristics of clinical blood use during the epidemic, it provides a reference for blood supply guarantee plan when the same epidemics occur in the future. Methods We reviewed blood use records of inpatient and emergency patient from January 21, 2020 to March 21, 2020 during the epidemic. Comparing with the same period last year, we analyzed blood use of inpatient and emergency patient. Result During the epidemic, the total amount of blood used in hospital was 10 616.3 U, and the total amount of red blood cells(RBCs) was 5 130.5 U (48.33%), of which the amount of blood used in outpatient and emergency patient was 1 410.5 U, and the amount of RBCs used was 1 037 U (73.52%). Compared with the same period last year, the total amount of blood used decreased by 5.88%, and RBCs decreased by 5.47%. RBCs amount in outpatient and emergency department accounted for 20.21% of total blood amount, compared with 13.23% in 2019. During the epidemic, the average RBCs amount per person and the rate of RBCs used were statistically significant, compared with the same period last year. The results also showed that RBCs amount in outpatient and emergency patient was mainly used by patients with gastrointestinal bleeding and hematological disease, and the blood amount used by patients with multiple injuries decreased significantly compared with the same period last year (90.38%). Among hospitalized patients, RBCs amount in surgical patients was significantly lower than that in patients treated with blood. Conclusion During the epidemic, our hospital significantly reduced total blood use. The amount of RBCs significantly increased in outpatient and emergency patient, but significantly decreased in patients with multiple injuries.

Objective The effect of novel coronavirus pneumonia on the antigenicity and antibody titer of some blood groups after 56℃ 30 min of virus inactivation was detected. Methods 20 samples with different blood types and 6 samples with different irregular antibodies were selected. Before and after the samples were heated and inactivated, the antigenicity and antibody titer of the samples were detected by microcolumn gel method. The antibody titer was determined by the agglutination intensity of 1+, and the changes of antigenicity and antibody titer of the samples before and after thermal inactivation were compared. Results The hemolysis of blood samples inactivated at 56 ℃ for 30 minutes was serious, which had no effect on the detection of ABO blood group antigen. The titer of irregular antibody decreased by 1~2 titers, the antibody with titer ≤ 4 would be missed, and the antibody with titer >4 would not be affected. Conclusion The heat inactivation of blood samples has certain influence on the antibody titer outside the ABO blood group system, but it can effectively reduce the risk of occupational exposure of operators.

Objective To study the changes of laboratory test indexes of pneumonia patients infected by novel coronavirus and its clinical significance to provide scientific reference for clinical diagnosis and treatment. Methods The relevant blood test indexes of 80 patients with new diagnosed novel coronavirus pneumonia admitted to our hospital in 2020 were retrospectively analyzed. Normal physical examination subjects were enrolled as Group A （n=40 cases）, patients with pneumonia suspected of novel coronavirus infection were Group B （n=40 cases） and patients with pneumonia diagnosed as novel coronavirus infection were Group C（n=80 cases）. The changes of laboratory blood routine, T lymphocyte subgroup and biochemical parameters in the three groups were compared. Results Compared with normal group A, WBC, L（%）, RBC, HGB, CD3⁺, CD4⁺, CD8⁺, BUN, UA, in confirmed group C were lower than those in normal group A, with statistical difference（P<0.05）;while G（%）, hs-CRP, ALT, AST, TB, DB, SAA, LDH, CK-MB in confirmed group C were higher than those in normal group A, with statistical difference（P<0.05）.Compared with suspected group B, CD4⁺、TnI are lower in confirmed group C than that in suspected group B, AST, SAA, LDH, CK-MB in confirmed group C are higher than those in suspected group B with statistical difference（P<0.05）. There was no significant difference in PLT, CD4⁺/CD8⁺, CR, CYC, PCT, MYO, CK among the three groups（P>0.05）. Multivariate logistic stepwise regression analysis showed that the higher are in SAA, CK-MB, LDH, AST\TB, DB, the greater is the risk of novel coronavirus pneumonia; The lower are in the WBC, L%, HGB, BUN, UA, CD4⁺, CD8⁺, the greater is the risk of novel coronavirus pneumonia. Conclusion The changes of various laboratory indexes in patients infected by novel coronavirus have obvious significance. These indexes have certain reference value for the early diagnosis and treatment of novel coronavirus.It is an effective supplement to nucleic acid test（a gold standard method）, which is helpful for clinical diagnosis of novel coronavirus pneumonia.

Objective We analyzed nucleic acid test results of 336 suspected novel coronavirus cases, and provided laboratory diagnostic evidence for novel coronavirus pneumonia control in Huainan. Methods According to the requirements of the "New Coronavirus Prevention and Control Plan （Fourth Edition, Fifth Edition）" promulgated by the general office of the National Health Commission, samples of throat swab and sputum were obtained from 336 suspected novel coronavirus cases in Huainan and laboratory nucleic acid detection were performed. The age, gender distribution, association between time after symptom onset and positive rates and specimen types were analyzed. Results From discovery to zero diagnosis in Huainan（from January 24, 2020 to February 19, 2020） , 336 suspected novel coronavirus cases were tested. The total number of positive nucleic acid test cases was 27, and positive rate was 8.04% （If any result of throat swab or sputum specimen is positive, the case is determined to be positive）. Of the 27 positive cases, 19 were familial aggregation. The youngest age of positive cases was 15 years, the oldest age was 78 years, and the median age was 40 years. Positive case was present in 15 （55.56%） males and in 12 （44.44%）females. Male: female ratio was 1.25∶1. The detection time for positive nucleic acid test cases was mainly 1st to 14th days from onset of symptoms, and the average onset time for positive nucleic acid tests was 5 days. Sputum specimens showed a higher positive rate than throat swabs. Sputum specimens showed a lower cycle threshold （Ct） value than throat swabs. 26 of 27 positive cases were mild and 1 was severe. As of 2nd March, 23 of 27 cases had been discharged from hospital, and the other 4 cases remained in stable condition. Conclusion The analysis of 336 novel coronavirus nucleic acid test results in Huainan would be useful for early diagnosis of COVID-19. When deciding on laboratory diagnosis and discharge criteria for COVID-19 patients, negative result of throat swab could not be used as exclusion criteria for infection and cure. It is necessary to test both patient's throat swab and sputum specimen at the same time for comprehensive judgment. Strengthening personal hygiene management and disinfecting crowded closed public places, is highly conducive to the prevention and control of COVID-19.

Objective To retrospectively analyze the use of intraoperative cell salvage （IOCS） and allogeneic blood transfusion in a tertiary hospital, and to evaluate effect of IOCS on allogeneic blood transfusion and its application in cesarean section. Methods A total of 8188 cesarean section cases from January 2015 to December 2018 were collected in a tertiary hospital.Allogeneic blood usage in non-implementation period （IOCS not applied from January 2015 to August 2016） was compared with that in implementation period （IOCS applied from September 2016 to December 2018）. The monthly IOCS use rate was compared with autologous blood transfusion rate during surgery in the implementation period. Results The average number of allogeneic red blood cell units and dose of allogeneic plasma during implementation period were significantly lower than those during non-implementation period （P<0.05）. During implementation period, the average age, placenta praevia, previous cesarean section rate, and IOCS usage increased year-over-year in 2016, 2017, and 2018, but the reinfused rate of IOCS did not change. Conclusion In recent years, the application of IOCS in cesarean section has reduced the demand for allogeneic blood transfusion, and there is still room for improvement in clinical indication selection.

Objective To study the effect of low-titre erythrocyte antibodies on tumor patients with blood transfusion in Xinjiang. Methods A retrospective analysis was performed on 667 cases of tumor patients in our hospital. According to the efficacy of blood transfusion, the patients were divided into effective group and ineffective group. The relationship between the transfusion efficacy and low titre antibody under the influence of different factors is analyzed. Results The effective infusion rate in this study is 81.86% and the incidence of adverse reactions is 0.45%. Invalid blood transfusion is closely related to pregnancy frequency, nationality and other factors, and the difference was statistically significant (P<0.05). The detection rate of low potency antibody is closely related to the number of pregnancies, previous blood transfusion history and national factors, and the difference was statistically significant (P<0.05). Compared with anti-human globulin method, the detection rate of low potency antibody is significantly different in various detection methods (P<0.05). Conclusion The inefficacy of transfusions exists in patients in this region, and the low potency antibody is one of the factors affecting the efficacy of blood transfusion. Medical institutions should reasonably set up re-examination rules to strengthen the detection of low-valency antibodies.

Objective To compare the effects of autotransfusion of pre-stored blood and allogeneic transfusion on the immune function and postoperative recovery of patients undergoing non-stop coronary artery bypass grafting. Methods Eighty-five patients who underwent non-stop coronary artery bypass grafting from February 2017 to February 2019 in our hospital were selected for the study. Among them, 48 patients with allogeneic blood transfusion were set as group A, and 37 patients who voluntarily received autotransfusion of pre-stored blood were set as group B the blood routine, coagulation function, cellular immune function, auxiliary ventilation time and ICU stay time before and after operation were compared between the two groups. Results 1 The RBC, Hb, PLT and HCT of the two groups decreased at 24 hours after operation (P<0.05), WBC of group B was lower than that of group A, RBC, Hb and PLT were higher than that of group A at 24 hours after operation (P<0.05); 2 Compared with before operation, the percentage of CD3⁺cells and CD8⁺cells in group A decreased and the percentage of CD4⁺cells increased at 24 hours after operation (P<0.05), the difference was statistically significant (P<0.05) .At 24 hours after operation, the percentage of CD3⁺cells and CD4⁺/CD8⁺ in group B was higher than that in group A, and the percentage of CD8⁺cells was lower than that in group A (P<0.05); 3 The time of auxiliary ventilation and ICU stay in group B were less than that in group A (P<0.05). Conclusion Autotransfusion of pre-stored blood can effectively improve the cellular immune function, balance the relationship between oxygen supply and demand, and reduce the time of auxiliary ventilation.

In recent years, with the rapid development of blood donation in Nanjing, many new problems and issues have emerged, and there is an urgent need for a new regional regulation. The newly formulated Nanjing Blood Donation Regulation have made innovations in establishment of a joint meeting system led by the government, setting of blood donating sites, information platform to shield high-risk group, system for blood usage reimbursement, and preferential policy for blood donors. We believe the local health legislation should have the courage to break through the shackles of departmental interests, actively respond to the development of health undertakings and the health demands of the people, and strengthen legal enforcement and supervision, so that the regulations could truly serve the development of regional blood collection and supply.

Objective To establish a traceability audit mode of blood collection and supply organization, and to improve the level of quality management system audit. Methods Under the centralized quality management audit, increase the traceability audit of blood products, facilities and equipment, key materials and personnel, and review the three links of compliance, adequacy and traceability between actual operations, quality system documentation and regulations. Results Through traceability audits, the risk management and control of each quality element is carried out to ensure the implementation of national laws and regulations, industrial standards and product quality requirements, and reduce potential safety hazards. Conclusion The traceability audit enhances the depth of internal audit of the quality management system, and supplements the content of internal audit of blood supply and blood supply organization.

Objective To explore the effect of rehabilitation training combined with Nalmefene on acute cerebral vasospasm of severe craniocerebral injury and its effect on endothelin-1 (ET-1) and nitric oxide (NO) production. Methods Seventy four patients with severe craniocerebral injury in the hospital were selected from January 2015 to December 2017. The patients were randomly divided into the control group (group A) and the observation group (group B), with 37 cases in each. The group A was treated with routine treatment combined with rehabilitation training whereas group B was additionally given Nalmefene. After 2 weeks of treatments, the two groups of patients were compared for blood flow velocity, incidence of cerebral vasospasm, Glasgow coma score, ET-1 and NO level, Fugl-Meyer assessment scale (FMA), and the Barthel index rating scale (BI) score. Results The blood flow velocity of all the patients in the two groups decreased following the treatments, particularly in group B when compared with the control (P<0.05). The incidence of CVS in group B was significantly lowered (P<0.05). After treatments, the GCS score of group B was significantly elevated (P<0.05). The ET-1 level of the cerebrospinal fluid in group B was decreased and the NO production was notably higher than that of the control (P<0.05). Generally, the scores of FMA and BI in both groups were improved but more obviously in group B than group A (P<0.05). Conclusion The combined therapy of rehabilitation training and Nalmefene may effectively reduce the secondary injury of brain tissues and help for amelioration of cerebral vasospasm, promotion of the recovery of consciousness and reduction of the ET-1 expression.

Objective To further study the diagnosis and treatment of CAR-T cell-related encephalopathy syndrome (CRES）and cytokine release syndrome (CRS), we reviewed two cases of CRES and CRS retrospectively. Methods Clinic data of two patients with relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL) after treated by CAR-T cell immunotherapy were analyzed combined with review of literature. Results Both of the two patients developed severe CRS (Grade 3) and CRES (Grade 3) .They were both developed epilepsy, hyperpyrexia, hypotension, hypoxia, tachycardia, and coagulation disorders. The level of C-reactive protein (CRP), Serum ferritin (SF), Interleukin (IL)-2, IL-6 and IL-10 were significant increased. The timing of onset for CRS were the 2th or 7th day after CAR-T cell transfusion, while CRES were 4th or 10th day, respectively. The first patient was treated with tocilizumab (8 mg/kg) and dexamethasone (20 mg/d), then clinical symptoms were obviously alleviated. The second patient was treated with tocilizumab (8 mg/kg) and dexamethasone (20mg/d), but still developed CRES, so switch to methylprednisolone (1 g/d), then the clinical symptoms were obviously alleviated. All of the two patients appeared to make a full recovery. Conclusion Monitoring of toxicities after CAR-T cell therapy and quick management of CRS and CRES are helpful for improvement of a clinical efficacy and safety in the treatment of CRES for patients with R/R B-ALL treated by CAR-T cell immunotherapy.

Objective To identify the expression level and clinical significance of plasma sCXCL16 in adult primary immune thrombocytopenia (ITP). Methods From December 2016 to December 2018, patients diagnosed with ITP at our hospital outpatient clinic were selected, including 46 active ITP, 42 ITP in remission and 40 health control group. The expression level of plasma sCXCL16 was detected by enzyme-linked immunosorbent assays (ELISA), and platelet (PLT) count, proportion of CXCR6 expression on lymphocyte subsets, CXCL16 and CXCR6 mRNA expression levels in peripheral blood mononuclear cells(PMBC) were detected respectively. Then, correlation of plasma sCXCL16 with disease course, bleeding and PLT were analyzed. Results Plasma sCXCL16 levels in active ITP patients were significantly higher than those in control group（P<0.05）and of patients in remission（P<0.05）, while PLT count in active ITP patients was significantly lower than that in the control group（P<0.05）and of patients in remission（P<0.05）. The proportion of CXCR6 expressed on CD4+ T cells, CD8⁺ T cells, and B cells in active ITP patients was significantly higher than that in control group and of patients in remission (P<0.05). PMBC CXCL16 mRNA and CXCR6 mRNA levels in active ITP patients were higher than those in control group and of patients in remission（P<0.05）. Plasma sCXCL16 in active ITP patients was not associated with disease course（r=-0.032, P=0.894）, nor did with PLT count（r=0.034, P=0.883）, while plasma sCXCL16 in active ITP patients was positively correlated with bleeding（r=0.532, P=0.025）; There was no correlation between plasma sCXCL16 levels and disease course, bleeding and PLT in patients with remission and normal control group（P>0.05）. Conclusion Plasma sCXCL16 levels might be involved in the pathogenesis of ITP by regulating the proportion of CXCR6 in lymphocyte subsets. It can be used as a biomarker to assess efficacy of ITP treatments.

Objective To analyze the drug resistance of Klebsiella pneumoniae and its distribution of plasmid mediated resistant genes. Methods A total of 115 K. pneumoniae isolates were collected and the drug susceptibility was determined by microdilution. PCR and DNA sequencing were used to detect the prevalence of extended ß-lactmase, AmpC enzyme, carbapenemase, 16S rRNA methylase encoding genes and the plasmid meidated quinolone resistance loci. The bacteria strains were divided into 2 groups according to the MIC of imipenem, the difference of the genetic distribution was compared. Results Over 30 percent of isolates showed non-sensitivity to antibiotics, and blaCTX-M-14 dominated in the blaESBL. The highest prevalence of oqxAB was noted, accounting for 60.9% and obviously higher in CSKP than in the CRKP. In comparison, the prevalence of blaCTX-M and blaTEM as well as rmtB was higher in CNSKP than that in CSKP（P<0.05）. Conclusion The rational use of antimicrobial agents and the implementation of infection control measures should be emphasized in order to inhibit the occurance of CNSKP by restricting the spread of resistant elements.

Objective To explore theapplicationvalue of combined detection of peripheral blood circulating tumor cells （CTCs） and cell-free DNA （cfDNA） in earlyscreening of liver cancer. Methods From September 2017 to August 2019, a total of one hundred and eighty-twohighly suspected liver cancer patients were enrolled in this study, who were divided into cancer group and benign group according to pathological results.T-testwas used for the difference of clinical data and CTCs/cfDNA. Pearson correlation analysis was employed to analyze the relationship between CTCs, cfDNA levels and liver function indexes and related tumor markers in cancer group. Receiver working characteristic （ROC）curves were used to evaluate diagnostic efficacy of CTCs and cfDNA detection in early liver cancer screening. Results The levels of AFP, γ- GT, CEA, ALT, AST, GGT, ALP and peripheral blood CTCs and cfDNA in cancer group were higher than benign group（P<0.05）.Pearson correlation analysis showed that the levels of CTCs and cfDNA were positively correlated with AFP, CEA and liver function（P<0.05）.There were significant difference between peripheral blood CTCs and cfDNA among different stages of liver cancer（P<0.05）. The ROC analysis showed that AUC of CTCsfor diagnosis of liver cance was 0.854, with cut-off 4 CTCs/5ml, with sensitivity and specificity was 75.54% and 86.05%, respectively; and that AUC of cfDNA was 0.831, with cut-off 19.38ng/ml, with sensitivity and specificity was 78.42% and 79.07%, respectively;butAUC, sensitivity and specificity of both indexsin the diagnosis of liver cancer were 0.923, 82.01% and 90.70%respectively. Conclusion The levels of CTCs and cfDNA in peripheral blood of patients with liver cancer are increased. The combined detection of CTCs and cfDNA has higher clinical value for early screening of liver cancer.

Objective To investigate the predictive role of serum carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA125) and carbohydrate antigen 199 (CA199) in prediction of the prognosis of advanced intrahepatic cholangiocarcinoma (ICC). Methods The clinical data of 120 patients with ICC in the hospital between 2015 and 2018 were retrospectively analyzed. The patients were divided into good prognosis and poor prognosis according to the disease progression and time of survival in one year follow-up. Logistic regression analysis was used to identify the related risk factors. Subject working curve was drawn, and the predictive significance of serum CEA, CA125, and CA199 was analyzed . Results Ninety-one patients had poor prognosis, including 72 deaths and 19 survivals with disease progression. The incidence of poor prognosis was 75.83%, with high levels of serum CEA, CA125 and CA199 (P<0.05). There were no significant differences between the two groups in gender, age, tumor diameter, hepatitis, cirrhosis, Child-Pugh classification, treatment methods as well as the blood AFP concentration (P>0.05). The independent risk factors for the patients with poor prognosis include multiple tumors, low differentiation and high TBIL≥171 μmol/mL (P<0.05). Logistic regression analysis showed that elevated CEA （>9.67 ng/mL）, CA125 (> 93.23 U/mL), CA199 (> 120.11 U/mL), and TBIL(>171 mmol/mL) and multiple tumors with low differentiation were independent risk factors for poor prognosis in patients with advanced ICC (P<0.05). The best cut-off points of serum CEA, CA125 and CA199 for predicting poor prognosis were 9.67 ng/mL, 93.23 U/mL and 120.11 U/mL, respectively. The sensitivity, specificity and accuracy of combined detections of serum CEA, CA125 and CA199 were higher than those of single detection, and the AUC of combined detection was 0.832, higher than that of single detection. Conclusion The serum levels of CEA, CA125 and CA199 are closely related to poor prognosis in patients with advanced ICC, and compared with the serum CEA, CA125 and CA199 detected alone, the serological indicators of the combination detection of the three have higher predictive value for prognosis of patients with advanced ICC.

Objective To evaluate the prognostic value of plasma homocysteine （Hcy） in patient with acute heart failure （AHF）. Methods From January 2018 to February 2019, 65 hospitalized patients with AHF or cardiac function capacity Ⅳ in Chaohu affiliated hospital of Anhui medical universty were selected as heart failure （HF） group, 65 patients without HF as control group at the same time. The above patients underwent plasma Hcy detection and echocardiography when they were admitted and were followed up for 6 months. Results Hcy plasma levels were significantly higher in AHF group than in control group. Hcy plasma levels were significantly positively associated with left ventricular end-diastolic diameter（LVEDD）, negatively with left ventricular ejection fraction （LVEF） and short axis shortening rate （FS）. In this study, 5 patients died and other 34 were readmitted within 6 months. 7 of which were readmitted due to cardiovascular events. 26 cases had satisfactory cardiovascular function controlled and no adverse events. Hcy levels were significantly higher in patients readmitted or died within 6 months than in patients without adverse events. Conclusion Hcy Plasma levels have good prognostic value for patients with AHF. Hcy is closely related to clinical and echocardiographic data, severity of HF and adverse outcomes.

MicroRNA（miRNA） is endogenously small non-coding regulatory RNA which plays important roles in many critical processes. It regulates gene expression through binding to the untranslated region of target mRNA. MicroRNA acts as a vital part in erythropoiesis. In this review, we mean to summarize the state of knowledge on the role of miRNAs in the regulation of different stages of erythropoiesis.