OBJECTIVES: To investigate the clinical and immunological features of children with primary immune thrombocytopenia (pITP) or connective tissue disease (CTD) with thrombocytopenia as the initial manifestation at initial diagnosis, and to provide a basis for early differentiation. METHODS: A retrospective study was performed on 236 children with pITP (pITP group) or CTD with thrombocytopenia as the initial manifestation (CTD-TP group) who were admitted from January 2019 to August 2024. Clinical and immunological indicators were compared between the two groups to identify potential influencing factors for early differentiation and their discriminative validity. RESULTS: Compared with the pITP group, the CTD-TP group had a significantly older age of onset and significantly lower leukocyte count, eosinophil count, lymphocyte count, and complement C4 level (P<0.05), as well as significantly higher levels of C-reactive protein, IgE, and IgM (P<0.05). The logistic regression analysis showed that age, IgE, IgM, total B cells, and complement C4 were predictive factors for early differentiation between pITP and CTD-TP (P<0.05). The receiver operating characteristic curve analysis showed that a combination of these five factors had a good discriminative validity, with an area under the curve of 0.944. The correlation analysis showed a negative correlation between IgG and platelet count in the pITP group (r_s=-0.363, P<0.05) and a positive correlation between NK cells and platelet count in the CTD-TP group (r_s=0.713, P<0.05). CONCLUSIONS There is heterogeneity in the clinical and immunological indicators between children with pITP and CTD-TP at initial diagnosis, and these research findings can help with the early differentiation between the two diseases.
Purpura, Thrombocytopenic, Idiopathic/immunology* ; Diagnosis, Differential ; Connective Tissue Diseases/immunology* ; Retrospective Studies ; Early Diagnosis ; Age of Onset ; Leukocyte Count ; Complement C4/immunology* ; C-Reactive Protein/immunology* ; Immunoglobulin E/immunology* ; Immunoglobulin M/immunology* ; Humans ; Male ; Female ; Infant ; Child, Preschool ; Child ; Adolescent ; Biomarkers/blood*

OBJECTIVE: To analyze the origin and influencing factors the titer of ABO blood group antibody in neonates. METHODS: A total of 303 newborn blood samples collected in our hospital from August 2023 to March 2024 were selected for the detection of ABO blood group settings and the determination of the total titers of IgG and IgM blood group antibodies in plasma. IgM antibodies were treated with dithithreitol (DTT) to determine the titers of IgG antibodies. The total titer of the blood group antibody was compared with that of the IgG antibody. The clinical data of mothers and newborns were collected, and the correlation between the antibody titer and these clinical data was analyzed. RESULTS: Among the 303 newborn specimens, 14 cases (4.62%) were identified to possess blood group antibodies. The influence of the maternal ABO blood group on the generation of high-potency blood group antibodies in newborns was observed to follow the order of O>B>A>AB, with a significant statistical difference ( P < 0.01). Of the 123 (40.59%) newborns born to mothers of type O, 121 (98.37%) had blood group antibody titers > 2. Of the 20 (6.60%) newborns born to mothers of type AB, all 20 (100.00%) had blood group antibody titers < 2. Among 89 (29.37%) mothers of type A and 71 (23.43%) mothers of type B, the titer of 100% newborn blood group antibody was less than 2, when the newborn blood group was incompatible with the mother's blood group; the titer of the newborn blood type antibody was higher or lower, when the newborn blood type was compatible with the mother's blood type. The titer of the newborn blood group antibodies is related to the number of pregnancies of the mothers and has no association with other clinical data (such as the mother's number of obortions), the number of production, fetal gestation age. CONCLUSION The majority of ABO blood group antibodies in neonates are IgG antibodies from the mothers, and few are produced by the neonates themselves. In some neonates, IgG anti-A and/or anti-B can agglutinate with anti-stereotyped cells at room temperature. The maternal ABO blood type is the primary factor influencing the titer of the newborn blood type. The number of maternal pregnancies is a factor affecting the high titer ABO blood group antibodies in newborns.
Humans ; Infant, Newborn ; ABO Blood-Group System/immunology* ; Female ; Immunoglobulin G/blood* ; Immunoglobulin M/blood* ; Pregnancy ; Blood Grouping and Crossmatching

Objective To prepare mouse monoclonal antibodies against the ectodomain of E2 (E2ecto) glycoprotein of Western equine encephalitis virus (WEEV). Methods A prokaryotic expression plasmid pET-28a-WEEV E2ecto was constructed and transformed into BL21 (DE3) competent cells. E2ecto protein was expressed by IPTG induction and presented mainly as inclusion bodies. Then the purified E2ecto protein was prepared by denaturation, renaturation and ultrafiltration. BALB/c mice were immunized with the formulated E2ecto protein using QuickAntibody-Mouse5W as an adjuvant via intramuscular route, boosted once at an interval of 21 days. At 35 days post-immunization, mice with antibody titer above 1×10⁴ were inoculated with E2ecto intraperitoneally, and spleen cells were fused with SP2/0 cells three days later. Hybridoma cells secreting specific monoclonal antibodies were screened by the limited dilution method, and ascites were prepared after intraperitoneal inoculation of hybridoma cells. The subtypes and titers of the antibodies in ascites were assayed by ELISA. The biological activity of the mAb was identified by immunofluorescence assay(IFA) on BHK-21 cells which were transfected with eukaryotic expression plasmid pCAGGS-WEEV-CE3E2E1. The specificity of the antibodies were evaluated with E2ecto proteins from EEEV and VEEV. Results Purified WEEV E2ecto protein was successfully expressed and obtained. Four monoclonal antibodies, 3G6G10, 3D7G2, 3B9E8 and 3D5B7, were prepared, and their subtypes were IgG2c(κ), IgM(κ), IgM(κ) and IgG1(κ), respectively. The titers of ascites antibodies 3G6G10, 3B9E8 and 3D7G2 were 10⁵, and 3D5B7 reached 10⁷. None of the four antibody strains cross-reacted with other encephalitis alphavirus such as VEEV and EEEV. Conclusion Four strains of mouse mAb specifically binding WEEV E2ecto are successfully prepared.
Horses ; Animals ; Mice ; Encephalitis Virus, Western Equine ; Ascites ; Immunosuppressive Agents ; Antibodies, Monoclonal ; Immunoglobulin M

The emerging of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused COVID-19 pandemic. The first case of COVID-19 was reported at early December in 2019 in Wuhan City, China. To examine specific antibodies against SARS-CoV-2 in biological samples before December 2019 would give clues when the epidemic of SARS-CoV-2 might start to circulate in populations. We obtained all 88,517 plasmas from 76,844 blood donors in Wuhan between 1 September and 31 December 2019. We first evaluated the pan-immunoglobin (pan-Ig) against SARS-CoV-2 in 43,850 samples from 32,484 blood donors with suitable sample quality and enough volume. Two hundred and sixty-four samples from 213 donors were pan-Ig reactive, then further tested IgG and IgM, and validated by neutralizing antibodies against SARS-CoV-2. Two hundred and thirteen samples (from 175 donors) were only pan-Ig reactive, 8 (from 4 donors) were pan-Ig and IgG reactive, and 43 (from 34 donors) were pan-Ig and IgM reactive. Microneutralization assay showed all negative results. In addition, 213 screened reactive donors were analyzed and did not show obviously temporal or regional tendency, but the distribution of age showed a difference compared with all tested donors. Then we reviewed SARS-CoV-2 antibody results from these donors who donated several times from September 2019 to June 2020, partly tested in a previous published study, no one was found a significant increase in S/CO of antibodies against SARS-CoV-2. Our findings showed no SARS-CoV-2-specific antibodies existing among blood donors in Wuhan, China before 2020, indicating no evidence of transmission of COVID-19 before December 2019 in Wuhan, China.
Humans ; Antibodies, Viral ; Blood Donors ; China/epidemiology* ; COVID-19/immunology* ; Immunoglobulin G ; Immunoglobulin M ; Pandemics ; SARS-CoV-2

Objective: To evaluate the association between immunoglobulin concentration and the risk of type 2 diabetes mellitus (T2DM) in adults in Tianjin City. Methods: Based on the Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIHealth) cohort from January 2010 to December 2018, subjects who had completed the measurement of baseline immunoglobulin concentration and blood glucose concentration and not been diagnosed with any type of diabetes at baseline were selected in this study. The collected data included the concentration of serum immunoglobulin (IgG, IgM, IgA and IgE), fasting blood glucose and other potential confounders. The subjects were divided into four groups from Q₁ to Q₄ according to the quartiles of baseline immunoglobulin concentration. The multivariable Cox regression model was used to assess the association between the baseline immunoglobulin concentration and T2DM. Results: A total of 6 315 subjects aged (50.1±10.0) years were included. About 390 subjects were newly diagnosed with T2DM during the follow-up period. The incidence rate was 16.8/1 000 person-years. After adjusting for age, sex, waist circumference, smoking status, drinking status, eosinophil ratio, metabolic syndrome, first-or second-degree family history, and reciprocal adjusting for other immunoglobulin concentrations, compared to the lowest quartile concentration group Q₁, subjects in group Q₄ with the highest quartile of IgG concentration showed a lower risk of T2DM (HR=0.71, 95%CI: 0.52-0.97), and subjects in group Q₄ with the highest quartile of IgM concentration also had a decreased risk of T2DM (HR=0.66, 95%CI: 0.47-0.91). Subjects in group Q₄ with the highest quartile of IgA concentration had an increased risk of T2DM (HR=1.56, 95%CI: 1.18-2.07). The risk of T2DM decreased with the increase of serum IgG and IgM concentrations (P_trend=0.018, P_trend=0.010) and increased with the increase of serum IgA concentrations (P_trend<0.001). No association was found between the concentration of IgE and T2DM risk (HR=0.99, 95%CI: 0.74-1.31, P_trend=0.891). Conclusion: The concentration of IgG and IgM is negatively associated with the risk of T2DM, and the concentration of IgA is positively associated with the risk of T2DM in Tianjin City. The concentrations of IgG, IgM and IgA could be a predictor of hyperglycemia and T2DM.
Humans ; Adult ; Diabetes Mellitus, Type 2 ; Prospective Studies ; Blood Glucose ; Inflammation/complications* ; Immunoglobulin A ; Immunoglobulin M ; Immunoglobulin G ; Immunoglobulin E ; Risk Factors

OBJECTIVE: To investigate whether anti-phosphatidylserine/prothrombin antibodies and its IgG or IgM subtypes were correlated with unexplained recurrent miscarriages. METHODS: In our a single-center retrospective study, 283 patients with at least one unexplained miscarriage who visited the Third Hospital of Peking University between January 2021 and August 2023, aged between 18-40 years, and tested for anti-phosphatidylserine/prothrombin antibodies IgG or IgM subtypes, were included. The patients with either positive IgG or IgM anti-phosphatidylserine/prothrombin antibody were regarded as positive for anti-phosphatidylserine/prothrombin antibody. SPSS 26.0 software was used for statistical analysis. Chi-square test and Logistic regression analysis were used to study the correlation of anti-phosphatidylserine/prothrombin antibodies and its IgG or IgM subtypes with unexplained recurrent miscarriages. And the diagnostic sensitivity, specificity, the positive predictive value, the negative predictive value of anti-phosphatidylserine/prothrombin antibodies and its IgG or IgM subtypes in unexplained miscarriages was calculated with four-fold table. RESULTS: Chi-square analysis showed that anti-phosphatidylserine/prothrombin antibodies and its IgM subtypes were correlated with recurrent miscarriages (both P < 0.05), while the IgG subtype was not correlated with recurrent miscarriages (P>0.05). After adjusting with anticardiolipin antibodies, anti-β₂ glycoprotein antibodies, lupus anticoagulants, antinuclear antibodies, and age by Logistic regression analysis, anti-phosphatidylserine/prothrombin antibodies were correlated with unexplained recurrent miscarriages (OR=2.084, 95%CI 1.045-4.155, P < 0.05), and anti-phosphatidylserine/prothrombin antibody IgM subtypes were correlated with unexplained recurrent miscarriages (OR=2.368, 95%CI 1.187-4.722, P < 0.05).The sensitivity of anti-phosphatidylserine/prothrombin antibody in recurrent miscarriage was 65.43%, the specificity was 48.51%, the positive predictive value was 33.76%, and the negative predictive value was 77.78%. In the patients with recurrent miscarriages with negative classical antiphospholipid antibodies, the sensitivity of anti-phosphatidylserine/prothrombin antibody was 59.09%, the specificity was 63.23%, the positive predictive value was 40.63%, and the negative predictive value was 78.40%. The sensitivity of the anti-phosphatidylserine/prothrombin antibody IgM subtype for the diagnosis of recurrent miscarriage was 65.43%, the specificity was 50.99%, the positive predictive value was 34.87%, and the negative predictive value was 78.63%. CONCLUSION Anti-phosphatidylserine/prothrombin antibody and IgM subtype antibody are correlated with unexplained recurrent miscarriages in patients with at least one unexplained miscarriage. Whether positive anti-phosphatidylserine/prothrombin antibody or IgM subtype could predict future unexplained recurrent miscarriages warrants a prospective study.
Pregnancy ; Female ; Humans ; Adolescent ; Young Adult ; Adult ; Prothrombin ; Retrospective Studies ; Phosphatidylserines ; Prospective Studies ; beta 2-Glycoprotein I ; Antibodies, Antiphospholipid ; Antiphospholipid Syndrome/diagnosis* ; Antibodies, Anticardiolipin ; Abortion, Habitual ; Immunoglobulin G ; Immunoglobulin M

OBJECTIVE: To investigate the role of multiple serological methods in the identification of complex antibodies. METHODS: The blood group antigens were detected by saline and microcolumn agglutination methods. The saline method was used to screen and identify IgM-type antibodies in the patient's serum, while the polybrene, anti-globulin, microcolumn agglutination, enzymic and absorption-elution methods were used to screen and identify IgG-type antibodies. RESULTS: The patient was B/CCDee/Jk(a-b+)/Fy(a-b+) blood type. The serum reacted with panel cells, and the reaction presented anti-E pattern in the saline medium. It was fully positive in the microcolumn agglutination card, except 2 negative ones after using papain to treat the panel cells. Referring to the pattern table, it was concluded that there existed anti-c, anti-E, and anti-Jk^a antibodies, and one antibody corresponding to an antigen that was easily destroyed by papain. The red blood cells with specific phenotype were selected for absorption-elution to identify IgG-type anti-c, anti-E, anti-Jk^a and anti-Fy^a antibodies. CONCLUSION It is confirmed that IgM-type anti-E, and IgG-type anti-c, anti-E, anti-Jk^a and anti-Fy^a antibodies exist in the patient's serum by multiple serological methods.
Humans ; Papain ; Blood Group Antigens ; Erythrocytes ; Immunoglobulin G ; Immunoglobulin M

OBJECTIVES: To investigate the change in the distribution of memory B cell subsets in children with frequently relapsing nephrotic syndrome (FRNS) during the course of the disease. METHODS: A total of 35 children with primary nephrotic syndrome (PNS) who attended the Department of Pediatrics of the Affiliated Hospital of Xuzhou Medical University from October 2020 to October 2021 were enrolled as subjects in this prospective study. According to the response to glucocorticoid (GC) therapy and frequency of recurrence, the children were divided into two groups: FRNS (n=20) and non-FRNS (NFRNS; n=15). Fifteen children who underwent physical examination were enrolled as the control group. The change in memory B cells after GC therapy was compared between groups, and its correlation with clinical indicators was analyzed. RESULTS: Before treatment, the FRNS and NFRNS groups had significantly increased percentages of total B cells, total memory B cells, IgD⁺ memory B cells, and IgE⁺ memory B cells compared with the control group, and the FRNS group had significantly greater increases than the NFRNS group (P<0.05); the FRNS group had a significantly lower percentage of class-switched memory B cells than the NFRNS and control groups (P<0.05). After treatment, the FRNS and NFRNS groups had significant reductions in the percentages of total B cells, total memory B cells, IgM⁺IgD⁺ memory B cells, IgM⁺ memory B cells, IgE⁺ memory B cells, IgD⁺ memory B cells, and IgG⁺ memory B cells (P<0.05) and a significant increase in the percentage of class-switched memory B cells (P<0.05). The FRNS group had a significantly higher urinary protein quantification than the NFRNS and control groups (P<0.05) and a significantly lower level of albumin than the control group (P<0.05). In the FRNS group, urinary protein quantification was negatively correlated with the percentage of class-switched memory B cells and was positively correlated with the percentage of IgE⁺ memory B cells (P<0.05). CONCLUSIONS Abnormal distribution of memory B cell subsets may be observed in children with FRNS, and the percentages of IgE⁺ memory B cells and class-switched memory B cells can be used as positive and negative correlation factors for predicting recurrence after GC therapy in these children.
Child ; Humans ; B-Lymphocyte Subsets/metabolism* ; Immunoglobulin E ; Immunoglobulin M ; Nephrotic Syndrome/immunology* ; Prospective Studies ; Glucocorticoids/therapeutic use*

OBJECTIVES: To study the effect of breastfeeding on immune function in infants with human cytomegalovirus (HCMV) infection. METHODS: A retrospective analysis was performed on the medical data of 135 infants with HCMV infection who were admitted to Children's Hospital Affiliated to Zhengzhou University from January 2021 to May 2022, and all these infants received breastfeeding. According to the results of breast milk HCMV-DNA testing, the infants were divided into two groups: breast milk HCMV positive (n=78) and breast milk HCMV negative (n=57). According to the median breast milk HCMV-DNA load, the infants in the breast milk HCMV positive group were further divided into two subgroups: high viral load and low viral load (n=39 each). Related indicators were compared between the breast milk positive and negative HCMV groups and between the breast milk high viral load and low viral load subgroups, including the percentages of peripheral blood lymphocyte subsets (CD3⁺ T cells, CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, and CD19⁺ B cells), CD4⁺/CD8⁺ ratio, IgG, IgM, IgA, and urine HCMV-DNA load. RESULTS: There were no significant differences in the percentages of CD3⁺ T cells, CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, and CD19⁺ B cells, CD4⁺/CD8⁺ ratio, IgG, IgM, IgA, and urine HCMV-DNA load between the breast milk HCMV positive and HCMV negative groups, as well as between the breast milk high viral load and low viral load subgroups (P>0.05). CONCLUSIONS Breastfeeding with HCMV does not affect the immune function of infants with HCMV infection.
Female ; Child ; Humans ; Infant ; Breast Feeding ; Cytomegalovirus Infections ; CD8-Positive T-Lymphocytes ; Retrospective Studies ; Infectious Disease Transmission, Vertical ; Milk, Human ; Cytomegalovirus ; Immunity ; Immunoglobulin A ; Immunoglobulin G ; Immunoglobulin M

Objective: To evaluate the association between immunoglobulin concentration and the risk of type 2 diabetes mellitus (T2DM) in adults in Tianjin City. Methods: Based on the Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIHealth) cohort from January 2010 to December 2018, subjects who had completed the measurement of baseline immunoglobulin concentration and blood glucose concentration and not been diagnosed with any type of diabetes at baseline were selected in this study. The collected data included the concentration of serum immunoglobulin (IgG, IgM, IgA and IgE), fasting blood glucose and other potential confounders. The subjects were divided into four groups from Q₁ to Q₄ according to the quartiles of baseline immunoglobulin concentration. The multivariable Cox regression model was used to assess the association between the baseline immunoglobulin concentration and T2DM. Results: A total of 6 315 subjects aged (50.1±10.0) years were included. About 390 subjects were newly diagnosed with T2DM during the follow-up period. The incidence rate was 16.8/1 000 person-years. After adjusting for age, sex, waist circumference, smoking status, drinking status, eosinophil ratio, metabolic syndrome, first-or second-degree family history, and reciprocal adjusting for other immunoglobulin concentrations, compared to the lowest quartile concentration group Q₁, subjects in group Q₄ with the highest quartile of IgG concentration showed a lower risk of T2DM (HR=0.71, 95%CI: 0.52-0.97), and subjects in group Q₄ with the highest quartile of IgM concentration also had a decreased risk of T2DM (HR=0.66, 95%CI: 0.47-0.91). Subjects in group Q₄ with the highest quartile of IgA concentration had an increased risk of T2DM (HR=1.56, 95%CI: 1.18-2.07). The risk of T2DM decreased with the increase of serum IgG and IgM concentrations (P_trend=0.018, P_trend=0.010) and increased with the increase of serum IgA concentrations (P_trend<0.001). No association was found between the concentration of IgE and T2DM risk (HR=0.99, 95%CI: 0.74-1.31, P_trend=0.891). Conclusion: The concentration of IgG and IgM is negatively associated with the risk of T2DM, and the concentration of IgA is positively associated with the risk of T2DM in Tianjin City. The concentrations of IgG, IgM and IgA could be a predictor of hyperglycemia and T2DM.
Humans ; Adult ; Diabetes Mellitus, Type 2 ; Prospective Studies ; Blood Glucose ; Inflammation/complications* ; Immunoglobulin A ; Immunoglobulin M ; Immunoglobulin G ; Immunoglobulin E ; Risk Factors