BACKGROUND: Macrophage polarization anomalies and dysfunction play a crucial role in the pathogenesis of immune thrombocytopenia (ITP). Itaconate is a Krebs cycle-derived immunometabolite synthesized by myeloid cells to modulate cellular metabolism and inflammatory responses. This study aimed to evaluate the immunoregulatory effects of an itaconate derivative on macrophages in patients with ITP. METHODS: Peripheral blood-derived macrophages from patients with ITP and healthy controls were treated with 4-octyl itaconate (4-OI), a derivative of itaconate that can penetrate the cell membrane. Macrophage polarization, antigen-presenting functions, and phagocytic capability were measured via flow cytometry and enzyme-linked immunosorbent assay (ELISA). Macrophage glycolysis in patients with ITP and the metabolic regulatory effect of 4-OI were detected using a Seahorse XFe96 Analyzer. An active murine model of ITP was used to evaluate the therapeutic effects of 4-OI in vivo . RESULTS: 4-OI reduced the levels of CD80 and CD86 in M1 macrophages and suppressed the release of tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 pro-inflammatory cytokines, suggesting that 4-OI could hinder the polarization of macrophages toward an M1 phenotype. We found that 4-OI pretreated M1 macrophages reduced the proliferation of CD4 + T cells and promoted the differentiation of regulatory T cells. In addition, after 4-OI treatment, the phagocytic capacity of M1 macrophages toward antibody-coated platelets decreased significantly in patients with ITP. In addition, the glycolytic function of M1 macrophages was elevated in individuals with ITP compared to those in healthy controls. 4-OI treatment downregulated glycolysis in M1 macrophages. The glycolysis inhibitor 2-deoxy-d-glucose (2-DG) also inhibited the polarization of M1 macrophages and restored their functions. In vivo , 4-OI treatment significantly increased platelet counts in the active ITP murine model. CONCLUSIONS Itaconate derivative 4-OI inhibited M1 macrophage polarization and restored impaired functions through metabolic reprogramming. This study provides a novel therapeutic option for ITP.
Macrophages/metabolism* ; Humans ; Animals ; Succinates/pharmacology* ; Mice ; Male ; Female ; Adult ; Middle Aged ; Flow Cytometry ; Tumor Necrosis Factor-alpha/metabolism* ; Enzyme-Linked Immunosorbent Assay ; Purpura, Thrombocytopenic, Idiopathic/metabolism* ; Glycolysis/drug effects* ; Metabolic Reprogramming

Objective To establish a sandwich enzyme-linked immunosorbent assay (ELISA) method for the quantitative detection of Chromogranin A (CHGA) in saliva, and to explore its preliminary application in the testing of saliva samples. Methods Recombinant human CHGA protein was used to immunize BALB/c mice, and monoclonal antibodies (mAbs) were prepared and screened using conventional hybridoma technology. A double-antibody sandwich ELISA detection method was constructed, and the matrix effect of saliva samples was optimized. This method was then applied to detect the concentration of CHGA in the saliva of stressed individuals. Results Twenty-one stable hybridoma cell lines secreting high affinity anti-human CHGA antibodies were obtained. A pair of detection antibodies with the best effect was selected, and the optimal coating concentration was determined to be 10 μg/mL, with the optimal dilution of detection antibodies being 1:32 000. The accuracy and reproducibility of this method were verified, with both intra-batch and inter-batch variation coefficients less than 15×, and the recovery rate between 80× and 120×. The matrix effect was further optimized to make it suitable for saliva sample detection. Saliva samples from individuals in different stress states were collected, and the CHGA levels were detected using the method established in this study, indicating its potential to reflect the intensity of stress. Conclusion A reliable saliva CHGA ELISA detection method has been successfully established, and its potential as a biomarker in stress-related research has been preliminarily explored.
Saliva/metabolism* ; Enzyme-Linked Immunosorbent Assay/methods* ; Humans ; Animals ; Mice, Inbred BALB C ; Mice ; Chromogranin A/immunology* ; Antibodies, Monoclonal/immunology* ; Female ; Male ; Reproducibility of Results ; Adult

Objective Currently, there is no commercially available quantitative detection kit for the main Felis domestic allergen (Fel d 1) in China. To establish a rapid detection method for Fel d 1, this study aims to prepare monoclonal antibodies against Fel d 1 protein. Methods The codon preference of Escherichia coli was utilized to optimize and synthesize the Fel d 1 gene. The prokaryotic expression plasmid pET-28a-Fel d 1 was constructed and used to express and purify the recombinant Fel d 1 protein. Subsequently, the recombinant protein was immunized into BALB/c mice and monoclonal antibodies (mAbs) were prepared by the hybridoma technique. An indirect ELISA was established using the recombinant Fel d 1 as the coating antigen, and hybridoma cell lines were screened for positive clones. The specificity and antigenic epitopes of the mAbs were confirmed by Western blot analysis. Finally, the selected hybridoma cells were injected into the peritoneal cavities of BALB/c mice for large-scale monoclonal antibody production. Results The recombinant plasmid pET-28a-Fel d 1 was successfully constructed, and soluble Fel d 1 protein was obtained after optimizing the expression conditions. Western blot and antibody titer assays confirmed the successful isolation of two hybridoma cell lines, 7D11 and 5H4, which stably secreted mAbs specific to Fel d 1. Antibody characterization revealed that the 5H4 mAb was of the IgG2a subtype and could recognize the amino acid region 105-163 of Fel d 1, while the 7D11 mAb was the IgG1 subtype and could recognize the amino acid region 1-59. Conclusion The high-purity recombinant Fel d 1 protein produced in this study provides a promising alternative for clinical immunotherapy of cat allergies. Furthermore, the monoclonal antibody prepared in this experiment lays a material foundation for the in-depth study of the biological function of Fel d 1 and the development of ELISA detection.
Animals ; Antibodies, Monoclonal/biosynthesis* ; Mice, Inbred BALB C ; Cats ; Mice ; Allergens/genetics* ; Glycoproteins/genetics* ; Enzyme-Linked Immunosorbent Assay ; Hybridomas/immunology* ; Recombinant Proteins/genetics* ; Female ; Antibody Specificity

Objective To prepare monoclonal antibodies against bovine CD4 and identify their basic biological characteristics. Methods Recombinant bovine CD4 (rHis-BoCD4 and rGST-BoCD4) was successfully expressed and purified by constructing a prokaryotic plasmid of bovine CD4 gene. The bovine CD4 monoclonal antibody was produced using hybridoma technology. The subtype and potency of the monoclonal antibody were identified and analyzed by ELISA, while specificity was analyzed through indirect immunofluorescence assay (IFA) and Western-blot. Results Four hybridoma cell lines, namely, 1H4, 6A10, 3F9 and 4G10, stably secreting monoclonal antibodies against BoCD4 were successfully obtained. The subclasses of the monoclonal antibodies subclass 6A10 was IgG2b and the rest of the monoclonal antibodies were of IgM type. Western-blot results showed that the four anti-bovine CD4 mAb strains were able to specifically bind to the bovine CD4 protein expressed in vitro. Indirect immunofluorescence assay showed that four monoclonal antibodies were able to specifically recognize the natural bovine CD4 protein. Flow cytometry assay showed that 3F9 was best to recognize bovine natural CD4 molecules. Conclusion Four monoclonal antibody strains with high specificity to natural bovine CD4 protein were successfully prepared, which lays the foundation for the subsequent studies on the function of bovine CD4 and diagnosis and treatment of bovine T-lymphocyte diseases.
Animals ; Antibodies, Monoclonal/isolation & purification* ; Cattle ; CD4 Antigens/genetics* ; Hybridomas/immunology* ; Antibody Specificity/immunology* ; Mice ; Mice, Inbred BALB C ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique, Indirect

Objective To investigate prokaryotic expression of the antigen sequence (amino acids 59-145) of mouse leukemia-related protein 16 (LRP16) protein and preparation of rabbit anti-mouse LRP16 polyclonal antibody. Methods The prokaryotic expression plasmid pLS962-LRP16 was constructed by the molecular cloning method and transferred into E.coli Rosetta to express LRP16 protein induced by IPTG. The recombinant protein was purified using Ni-NTA affinity columns followed by gel filtration chromatography. New Zealand white rabbits were immunized with the purified antigen to generate polyclonal antiserum, with antibody titer quantified by ELISA. Antigen-specific IgG was affinity-purified using Sepharose-coupled LRP16 and validated through Western blot and immunofluorescence assays. Results SDS-PAGE analysis confirmed insoluble expression of the LRP16 fusion protein as inclusion bodies. ELISA demonstrated exceptional antiserum titer (1:256 000). Western blot and immunofluorescence verified that the polyclonal antibody could specifically recognize endogenous LRP16 in murine tissues. Conclusion The prokaryotic expression of the LRP16 gene is successfully achieved, and the rabbit anti-mouse LRP16 polyclonal antibody exhibiting high specificity is prepared. This lays the foundation for further studies on the function of the LRP16 gene.
Animals ; Rabbits ; Mice ; Antibodies/immunology* ; Escherichia coli/metabolism* ; Enzyme-Linked Immunosorbent Assay ; Blotting, Western ; Antibody Specificity

OBJECTIVE: To investigate the serological prevalence of high-titer IgG antibodies against 2019-nCoV among voluntary blood donors in Zunyi. METHODS: The blood plasma specimens were diluted at 1∶160 or 1∶320, then tested for the presence of 2019-nCoV IgG antibodies by using an indirect enzyme-linked immunosorbent assay(ELISA). The differences of antibody reactive rate among different genders, ages, and blood types were analyzed. RESULTS: 1 523 reactive specimens were identified in 5 378 specimens which were diluted at a ratio of 1∶160. Similarly, 329 reactive specimens were identified in 2 988 diluted at 1∶320. The overall reactive rate for antibodies was 22.1%. It was observed that females, individuals over the age of 40, and those with blood type AB exhibited higher high-titer antibody reactive rate. CONCLUSION After entering a new stage of 2019-nCoV infection prevention and control, there is a relatively high detection rate of high-titer 2019-nCoV IgG antibodies among voluntary blood donors in Zunyi. The reactive rate of antibodies varies among different genders, ages, and blood types.
Humans ; Blood Donors ; Immunoglobulin G/blood* ; Antibodies, Viral/blood* ; SARS-CoV-2/immunology* ; COVID-19 ; Female ; Enzyme-Linked Immunosorbent Assay ; Adult ; China ; Male ; Middle Aged

OBJECTIVE: To study the results, re-donation situation and characteristics of single-reagent reactive blood donors who were put into the reentry strategy in Wuhan area, explore the rationality and effectiveness of the current reentry strategy, and provide data support for the improvement of the reentry process of blood donors. METHODS: From January 2020 to December 2023, blood donors who conform the reentry criteria and voluntarily applied for returning to Wuhan Blood Center were tested and the results were analyzed. According to the reentry strategy, serological testing and nucleic acid testing were carried out in parallel, serological testing was performed by ELISA with reagents from two different manufacturers, and the primary reactive samples were tested by double-well retest, and HBV/HCV/HIV nucleic acid detection was performed by RT-PCR with an individual donor test mode. Supplementary HBcAb testing was applied for HBV single reagent reactivity by chemiluminescence method. Supplementary TP-WB testing was applied for returning blood donors with repeated TP single reagent reactivity. If returning blood donors with HIV single reagent reactivity were repeated single reagent reactivity, the samples were sent to local CDC for confirmatory test. RESULTS: 7 098 blood donors were qualified for reentry, 716 donors voluntarily applied for reentry, 436 donors successfully reentry, 251 donors entered the next round, 29 donors could not reentry. The reentry rates for the past four years were 66.67%（42/63）, 54.73%（81/148）, 60.71%（136/224） and 62.99%（177/281）, respectively. Up to December 31, 2023, 275 donors donated blood again, and the donation rates for past four years were 76.19%（32/42）, 72.84%（59/81）, 61.76%（84/136） and 56.50%（100/177）, respectively. After donating blood, 31 donors were disqualified again by blood screening and subjected to permanent deferral. The results of returning to the team had statistical differences in reentry items, educational level, age, and marriage（P < 0.05）. CONCLUSION The current reentry strategy adopted by the blood donation and supply institution can effectively retain part of blood donors, reduce the negative emotions of blood donors and increase blood resources.
Humans ; Blood Donors ; China ; Hepatitis B ; Enzyme-Linked Immunosorbent Assay ; Hepatitis C ; Male

OBJECTIVE: To investigate the serum level of lumican (LUM) and its clinical correlation with disease and immune activities in patients with rheumatoid arthritis (RA). METHODS: The serum LUM levels in both RA patients and health controls (HCs) were detected by enzyme-linked immunosorbent assay (ELISA). The clinical and laboratory data of the patients were collected. The LUM levels in the patients with different clinical features were analyzed. The correlation between the clinical data, laboratory parameters, and serum LUM levels were also analyzed. Independent samples t test, Spearman correlation were used for statistical analysis. Analysis of variance and Kruskal-Wallis test, the least significant difference (LSD)-t test and Bonferroni correction were used for statistical analysis. The Pearson Chi-square test was used for comparison of the rates between the groups. Statistical significance was set at P < 0.05. RESULTS: The levels of LUM were elevated in the RA patients than in the HCs (P < 0.000 1). Serum LUM levels were correlated with the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), immunoglobulin A (IgA), titers of platelet (PLT) and 28-joint disease activity score (DAS28, all P < 0.05). Next, we compared the serum LUM levels in the RA patients with different characteristics, and no difference was found in serum LUM levels between early-RA and RA, the same to RA with different gender (P>0.05). The levels of serum LUM were elevated in the RF positive patients (P < 0.000 1), and in the RF and anti-CCP positive patients (P < 0.05) than in the RA patients with negative RF whether the anti-CCP was positive. In addition, no differences were found between the RA patients with negative RF whether the anti-CCP was positive (P>0.05). All the levels of serum LUM were elevated in the RA patients with different CRP or ESR than in the HCs (P < 0.05), and the serum LUM levels in the RA patients with elevated ESR and CRP were significantly elevated in those with normal ESR and CRP (P < 0.05). Additionally, the results demonstrated that serum LUM levels were positively associated with RA disease activity, and they were declined in RA sustained remission than those in middle or high disease activity (P < 0.05). Furthermore, no difference was found between the RA patients in remission and HCs (P>0.05). No differences were found in the RA patients with and without complications including interstitial pneumonia disease, Sjögren's syndrome, thyroid gland diseases and osteoporosis (P>0.05). The LUM positivity rates were significantly elevated in the RF positive patients than the RF negative patients in RA (P < 0.05). CONCLUSION LUM, a cyclocitrullinated protein, might be a promising biomarker which could reflect both disease activity and immune activity in RA.
Humans ; Arthritis, Rheumatoid/immunology* ; Lumican/blood* ; C-Reactive Protein/metabolism* ; Female ; Male ; Rheumatoid Factor/blood* ; Middle Aged ; Adult ; Chondroitin Sulfate Proteoglycans/blood* ; Blood Sedimentation ; Keratan Sulfate/blood* ; Enzyme-Linked Immunosorbent Assay ; Aged

Ten novel xanthones, garpedunxanthones A-G (1-5, 6a/6b, 7a/7b) and nujiangxanthone Q (8), along with sixteen known analogs (9-24), were isolated from Garcinia pedunculata and G. nujiangensis. Their structures were elucidated through high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) data, comprehensive nuclear magnetic resonance (NMR) spectroscopic analyses, and electronic circular dichroism (ECD) calculations. All compounds without cytotoxicity were assessed for anti-inflammatory properties by measuring the inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 cells. Structure-activity relationships are also discussed. Compounds 7b, 19, and 21 exhibited significant anti-inflammatory activity with IC₅₀ values of 16.44 ± 0.69, 14.28 ± 0.78, and 10.67 ± 3.28 μmol·L^-1, respectively. Enzyme-linked immunosorbent assay (ELISA) demonstrated that compounds 7b, 19, and 21 inhibited the expression of pro-inflammatory cytokines TNF-α and IL-6 in a dose-dependent manner. The inhibitory effect of compound 21 on IL-6 at 20 μmol·L^-1 was comparable to that of the positive control. In network pharmacology studies, potential targets of compounds and inflammation were identified from PharmMapper and GeneCards databases. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that the overlapped targets were intricately associated with major pathogenic processes linked to inflammation, including positive regulation of mitogen-activated protein kinase (MAPK) cascade, protein kinase activity, NO synthase regulator activity, MAPK signaling pathway, and EGFR tyrosine kinase inhibitor resistance.
Xanthones/therapeutic use* ; Garcinia ; Anti-Inflammatory Agents/therapeutic use* ; Plant Preparations/therapeutic use* ; Structure-Activity Relationship ; Nitric Oxide/metabolism* ; RAW 264.7 Cells ; Animals ; Mice ; Enzyme-Linked Immunosorbent Assay ; Mitogen-Activated Protein Kinase Kinases/metabolism* ; Circular Dichroism

Senecavirus A (SVA) is a major viral pathogen causing disease in pigs, and effective monitoring of SVA infection is critical for disease control. In this study, we aimed to develop a reliable ELISA method for rapidly detecting neutralizing antibodies against SVA. We used HEK293F cells to express an SVA-specific porcine Fab antibody and verified the biological activity of the Fab antibody by indirect ELISA, immunofluorescence assay, virus neutralization test, and Western blotting. The Fab antibody was biotinylated and used as a competitive antibody to establish a competitive ELISA (C-ELISA) for detecting neutralizing antibodies against SVA. We then evaluated the C-ELISA in terms of sensitivity, specificity, repeatability, and result agreement rate with the VNT. The results showed that we successfully prepared an SVA-specific porcine Fab antibody, which showed high affinity for SVA. We named this antibody 1M33Fab and designated it as Bio-1M33Fab after biotin labeling. The assay conditions were optimized as follows: the coating concentration of SVA particles being 1 μg/mL, the working concentration of Bio-1M33Fab being 0.5 μg/mL, the optimal serum dilution of 1:10, and the optimal dilution of enzyme-labeled avidin being 1:30 000. At a percent inhibition (PI) of 47%, the assay demonstrated the highest sensitivity (96.88%) and specificity (100%), with no cross-reactivity observed with the positive sera of major porcine viral diseases. The intra-assay coefficient of variation ranged from 1.12% to 7.34%, while the inter-assay coefficient of variation ranged from 1.10% to 8.97%, indicating good repeatability. In the detection of 224 clinical pig serum samples, C-ELISA and VNT showed a result agreement rate of 93.75%. In conclusion, we successfully develop a C-ELISA method for detecting neutralizing antibodies against SVA by using a porcine-derived Fab antibody, which lays a foundation for the development of detection kits.
Animals ; Swine ; Antibodies, Neutralizing/immunology* ; Enzyme-Linked Immunosorbent Assay/methods* ; Immunoglobulin Fab Fragments/immunology* ; Antibodies, Viral/immunology* ; Picornaviridae/immunology* ; Humans ; HEK293 Cells ; Swine Diseases/diagnosis* ; Picornaviridae Infections/diagnosis*