Research on IgG4-related disease (IgG4-RD), an autoimmune condition recognized to be a unique disease entity only two decades ago, has processed from describing patients' symptoms and signs to summarizing its critical pathological features, and further to investigating key pathogenic mechanisms. Challenges in gaining a better understanding of the disease, however, stem from its relative rarity-potentially attributed to underrecognition-and the absence of ideal experimental animal models. Recently, with the development of various high-throughput techniques, "omics" studies at different levels (particularly the single-cell omics) have shown promise in providing detailed molecular features of IgG4-RD. While, the application of omics approaches in IgG4-RD is still at an early stage. In this paper, we review the current progress of omics research in IgG4-RD and discuss the value of machine learning methods in analyzing the data with high dimensionality.
Humans ; Immunoglobulin G4-Related Disease/metabolism* ; Immunoglobulin G/metabolism* ; Machine Learning ; Animals ; Proteomics/methods*

Objective To explore the effect of Evodiamine (Evo) on the immune function of allergic rhinitis (AR) rats and the regulatory mechanism on C-C motif chemokine ligand 2 (CCL2)/ C-C motif chemokine receptor 2 (CCR2) pathway. Methods The related targets of Evo-AR-immune function were screened by network pharmacology, and the protein interaction network diagram of intersecting targets was constructed. The AR rat model was established by ovalbumin (OVA) combined with aluminium hydroxide, and the rats were divided into six groups: a normal control (NC) group, a model group, a Loratadine (LOR) group, an Evodiamine low dose (Evo-L) group, a Evodiamine high dose (Evo-H) groups, and an Evo-H combined with CCL2 group. After the last administration, the symptoms of rats in each group were scored; ELISA was applied to detect the levels of histamine, immunoglobulin E (IgE), interleukin 4 (IL-4), IL-13 and interferon γ (IFN-γ); Diff-Quick staining solution was applied to detecte the number of cells in the nasal lavage fluid (NALF); hematoxylin eosin (HE) staining was applied to observe the pathological changes of nasal mucosa tissue; real-time quantitative PCR was applied to detect the levels of CCL2 and CCR2 mRNA in tissue; Western blot was applied to detect the expression levels of CCL2, CCR2 and CXC motif chemokine ligand 8 (CXCL8) proteins in nasal mucosa. Results There were eight intersection targets of EVo-AR-immune function, and protein interaction network diagram showed that CXCL8 was the core target. Compared with the NC group, the score of nasal symptoms, the levels of histamine, IgE, IL-4 and IL-13, the numbers of eosinophil, macrophages, neutrophils, lymphocytes and total cells, the mRNA and protein expression levels of CCL2 and CCR2, and the expression of CXCL8 protein in the model group were increased, while the level of IFN-γ was decreased. Compared with the model group, the score of nasal symptoms, the levels of histamine, IgE, IL-4 and IL-13, the numbers of eosinophil, macrophages, neutrophils, lymphocytes and total cells, the mRNA and protein expression levels of CCL2 and CCR2, and the expression of CXCL8 protein in LOR and Evo groups were decreased, while the level of IFN-γ was increased. Further use of CCL2 recombinant protein for compensatory experiments revealed that the improvement effect of Evo on immune function in AR rats was reversed by CCL2. Conclusion Evo can improve the immune function of AR rats, and its mechanism may be related to the inhibition of the CCL2/CCR2 pathway.
Animals ; Receptors, CCR2/immunology* ; Signal Transduction/drug effects* ; Chemokine CCL2/immunology* ; Rats ; Rhinitis, Allergic/metabolism* ; Immunoglobulin E/blood* ; Quinazolines/pharmacology* ; Male ; Interferon-gamma ; Rats, Sprague-Dawley ; Interleukin-13 ; Histamine ; Interleukin-4/immunology* ; Disease Models, Animal

OBJECTIVES: To explore the lipidomic characteristics of children with bronchial asthma (hereafter referred to as asthma) and identify potential biomarkers for asthma. METHODS: A total of 26 asthmatic children were prospectively enrolled as the asthma group, and 20 healthy children served as the healthy control group. The asthma group was further divided into atopic (n=13) and non-atopic (n=13) subgroups based on IgE levels. Serum lipid metabolites were analyzed using liquid chromatography-mass spectrometry, followed by statistical analysis and data visualization. RESULTS: A total of 1 435 lipids were detected in the 46 children, primarily glycerophospholipids (625/1 435, 43.55%). Significant differences were observed in serum lipid profiles between the asthma and control groups. Twelve significantly differential lipids were identified, with receiver operating characteristic curve analysis showing that phosphatidylserine (PS)(18:0/20:4) and ceramide (Cer)(c16:0) exhibited the highest diagnostic value for asthma. The relative abundances of PS(18:0/20:4) and PS(18:0/22:6) were higher in the atopic subgroup than in the non-atopic subgroup (P<0.05) and positively correlated with total IgE levels in asthmatic children (r=0.675 and 0.740, respectively; P<0.05). CONCLUSIONS Asthmatic children exhibit significant lipid metabolic disturbances, primarily characterized by abnormal glycerophospholipid metabolism. Among these, PS(18:0/20:4) and Cer(c16:0) demonstrate specific alterations and may serve as potential diagnostic biomarkers for asthma. Furthermore, the positive correlation between PS(18:0/20:4) and PS(18:0/22:6) levels and serum total IgE suggests their possible involvement in immune regulation in asthma.
Humans ; Asthma/metabolism* ; Male ; Child ; Female ; Prospective Studies ; Mass Spectrometry/methods* ; Lipids/blood* ; Chromatography, Liquid/methods* ; Child, Preschool ; Immunoglobulin E/blood* ; Biomarkers/blood* ; Adolescent ; Liquid Chromatography-Mass Spectrometry

OBJECTIVE: To investigate the relationship between Ig class switch recombination (CSR) and mismatch repair (MMR) protein, microsatellite phenotype in extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma). METHODS: Forty cases of MALT lymphoma archived in the Department of Pathology, Jiading District Central Hospital, Shanghai University of Medicine & Health Sciences were selected as the observation group, and twenty cases of benign lymphoid tissue hyperplasia were as the control group. The expressions of IgG, IgM, IgD, and IgA in both groups were detected by immunohistochemical double staining, and MMR proteins including MLH1, MSH2, MSH6, and PMS2 in both groups were detected by immunohistochemistry. Multiplex fluorescence PCR capillary electrophoresis was used to detect microsatellite phenotype in tumor and adjacent tissues of the experimental group. RESULTS: In the observation group, the proportions of single Ig heavy chain expression (modeⅠ), negative expression (modeⅡ), and multiple expression (mode Ⅲ) were 65% (26/40), 27.5% (11/40), and 7.5% (3/40), respectively, while in the control group were 0 (0/20), 5% (1/20), and 95% (19/20). The proportion of Ig heavy chain expression mode Ⅰ+Ⅱ in the observation group was 92.5%, which was significantly higher than 5% in the control group (P < 0.01). In the observation group, partial deletion of MMR protein was observed in 3 cases (7.5%), including 2 cases of MSH6 deletion and 1 case of both MSH6 and PMS2 deletion. In the control group, there was 1 case (5%) with PMS2 deletion. There was no significant difference in the deletion rate of MMR protein between the two groups ( P >0.05). A total of 5 cases of microsatellite instability (MSI) were detected in the observation group, including 1 case of low-frequency MSI (MSI-L), 4 cases of high-frequency MSI (MSI-H), and 2 cases of MSI-H with MSH6 deletion. When the loss expression of MSI-H or MMR protein was counted as a positive result, the MSI-H rate detected by PCR capillary electrophoresis was 10% (4/40), which was slightly higher than the MMR protein deletion rate detected by immunohistochemistry (7.5%, 3/40), but there was no statistically significant difference between the two groups (P >0.05). The MMR protein deletion rates among the Ig heavy chain protein expression mode Ⅰ, mode Ⅱ, and mode Ⅲ groups were 0 (0/26), 18.2% (2/11), and 33.3% (1/3), respectively. There was a statistically significant difference in the constituent ratios among the three groups (P < 0.05). The MMR protein deletion rates among the MSS, MSI-L, and MSI-H groups were 2.9% (1/35), 0 (0/1), and 50% (2/4), respectively. There was a statistically significant difference in the constituent ratios among the three groups (P < 0.05). MMR protein deficiency was positively correlated with Ig heavy chain expression pattern and MSI ( r =0.41, P < 0.05; r =0.48, P < 0.05), but Ig heavy chain expression pattern was not correlated with MSI ( r =0.02, P >0.05). CONCLUSION Ig heavy chain CSR detection is helpful for the differential diagnosis of MALT lymphoma. Low frequency MMR protein deletion and MSI-H phenotype exist in MALT lymphoma, which may be of certain value for the study of its occurrence, development and clinical treatment.
Humans ; Lymphoma, B-Cell, Marginal Zone/genetics* ; DNA Mismatch Repair ; Immunoglobulin Class Switching ; DNA-Binding Proteins/metabolism* ; MutS Homolog 2 Protein ; Microsatellite Repeats ; Phenotype ; MutL Protein Homolog 1 ; Mismatch Repair Endonuclease PMS2 ; Male

OBJECTIVE: To explore the role of semaphorin 4D (Sema4D) in immunoglobulin A (IgA) -mediated immune abnormalities in B lymphocytes of pediatric Henoch-Schonlein purpura (HSP). METHODS: One hundred HSP children admitted to Hengshui People's Hospital from January 2022 to January 2023 were selected as HSP group, and one hundred healthy children as control group. Sema4D expression was detected, and the relationship between Sema4D expression in children's serum and skin lesions and clinical characteristics of children was analyzed. Sema4D expression on the surface of lymphocytes of HSP children was detected. Different concentrations of human recombinant Sema4D protein was used to stimulate peripheral blood mononuclear cells in HSP children in vitro. The expression level of IgA in the supernatant was detected to verify whether Sema4D mediates immune abnormalities through IgA secreted by B lymphocytes. RESULTS: The Sema4D level in the HSP group was significantly higher than that in the control group (P <0.001). Sema4D level in HSP children with severe, renal involvement, and joint involvement was higher than those with mild to moderate disease, and no renal or joint involvement (all P <0.001). Compared with control group, IgA level, CD8 ⁺ T lymphocyte proportion, and CD19 ⁺ B lymphocyte proportion in the HSP group were significantly higher but CD4 ⁺ T lymphocyte proportion was lower (all P <0.001). The expression levels of Sema4D on the surface of CD4 ⁺ T lymphocytes, CD8 ⁺ T lymphocytes, and CD19 ⁺ B lymphocytes in the HSP group were significantly higher than those in the control group (all P <0.001). With the increase of human recombinant Sema4D protein concentration, the level of IgA expression in HSP children gradually increased (P <0.05). Correlation analysis showed that Sema4D was significantly positively correlated with IgA (r =0.667). CONCLUSION HSP children show high expression of Sema4D, especially on the surface of T and B lymphocytes. The shedding of Sema4D from membrane surface may stimulate B lymphocytes to secrete IgA by binding to CD72, leading to immune abnormalities.
Humans ; IgA Vasculitis/immunology* ; Semaphorins/metabolism* ; B-Lymphocytes/metabolism* ; Immunoglobulin A/immunology* ; Child ; Antigens, CD/metabolism* ; Male ; Female ; Child, Preschool

OBJECTIVES: This study aimed to explore the therapeutic effect and mechanism of ginsenoside Rb3 on experimental periodontitis and bone resorption in rats. METHODS: Male SD rats were randomly divided into a control group, a ligation group, an Rb3 group, and a doxycycline (Dox) group for in vivo experiments. A periodontitis model was established by ligating the maxillary second molar, and samples were collected after 3 weeks of drug treatment. Micro-CT assessment of alveolar bone resorption was performed, and hematoxylin-eosin (HE) staining was used to observe pathological changes in periodontal and visceral tissues. Tartrate resistant acid phosphatase (TRAP) staining was applied to detect the formation of osteoclasts in periodontal tissues, and enzyme-linked immunosorbent assay (ELISA) was adopted to detect the serum levels of interleukin (IL)-6, IL-8, immunoglobulin (Ig)M, and IgG. Quantitative polymerase chain reaction (qPCR) was employed to detect the expression of factors related to gingival inflammation and osteoclast formation. Immunofluorescence staining was used to detect phospho-extracellular signal-regulated kinase (p-ERK) expression. In vitro experiments were conducted by pretreating RAW264.7 cells with drugs and adding lipopolysaccharides (LPS) stimulation from Porphyromonas gingivalis (P. gingivalis). IL-1β and IL-6 mRNA expression was detected by qPCR, and Western blot was used to detect the effect of Rb3 on the mitogen-activated protein kinases (MAPKs) signaling pathway. RESULTS: Compared with the control group, the ligation group showed significant periodontitis and bone resorption. Compared with the ligation group, the Rb3 group showed a decrease in alveolar bone resorption and osteoclast formation; p-ERK/ERK ratio, IL-1β, IL-6, and nuclear factor of activated T cells (NFATc1) mRNA levels and downstream gene expression in periodontal tissues; serum IL-6, IL-8, IgG, and IgM levels. Rb3 reduced IL-8 and IL-1β mRNA expression levels and p-ERK/ERK and p-p38 MAPK/p38 MAPK ratios in RAW264.7 cells induced by P. gingivalis LPS stimulation. CONCLUSIONS Rb3 inhibits inflammation and bone resorption in experimental periodontitis in rats. Compared with Dox, Rb3 has better effects in inhibiting pro-inflammatory factors and osteoclast gene expression and may exert anti-inflammatory effects by activating the MAPK signaling pathway.
Animals ; Ginsenosides/therapeutic use* ; Rats, Sprague-Dawley ; Male ; Periodontitis/pathology* ; Rats ; Osteoclasts/drug effects* ; Interleukin-1beta/metabolism* ; Interleukin-6/blood* ; Mice ; Alveolar Bone Loss ; Interleukin-8/blood* ; Immunoglobulin G/blood* ; RAW 264.7 Cells ; Transcription Factors

In this study, we constructed a series of recombinant Fc variants of immunoglobulin G4 (IgG4), screened the fragment crystallizable (Fc) variants with significantly prolonged serum half-lives, and analyzed the relationship between mutation site and half-life, aiming to provide a theoretical basis for the development of IgG4 antibodies and Fc fusion protein-based drugs. Nine gene sites were selected for mutation, and different mutation sites were combined. The variant expression plasmids pET24b-Fc were constructed by molecular cloning and point mutation. The plasmids were transformed into Escherichia coli BL21(DE3) for the expression of different recombinant proteins of Fc. Fc2 and Fc3 variants had slightly lower recombinant protein yields, and the expression of other variants was not affected. The toxicity of different Fc variants was determined by cell counting kit-8 (CCK-8) and calcein acetoxymethyl ester/ propidium iodide (calcein AM/PI) in vitro and enzyme-linked immuno sorbent assay (ELISA) in vivo. The results showed that the recombinant Fc variants had good biocompatibility and safety. Finally, the Fc variants were labeled with fluorescent markers, and the effects of different mutations on their serum half-lives were investigated by in vivo experiments. The Fc5 variant with prolonged serum half-life was successfully screened out, which provided a theoretical and practical basis for the optimal design of IgG4 subtype antibody and Fc fusion protein drugs.
Immunoglobulin G/blood* ; Immunoglobulin Fc Fragments/biosynthesis* ; Half-Life ; Animals ; Escherichia coli/metabolism* ; Humans ; Recombinant Fusion Proteins/biosynthesis* ; Recombinant Proteins/biosynthesis* ; Mice

This study aimed to investigate the mechanism by which Shegan Mahuang Decoction(SGMH) and its bitter Chinese herbs(BCHs) regulated the lung-gut axis through the bitter taste receptor 14(TAS2R14)/secretory immunoglobulin A(SIgA)/thymic stromal lymphopoietin(TSLP) to intervene in the epithelial cell barrier of cold asthma rats. Fifty SD rats were randomly divided into the following five groups: normal group, model group, dexamethasone group, SGMH group, and BCHs group. A 10% ovalbumin(OVA) solution was used to sensitize the rats via subcutaneous injection on both sides of the abdomen and groin, combined with 2% OVA atomization and cold(2-4 ℃) stimulation to induce a cold asthma model in rats. The SGMH, BCHs, and dexamethasone groups were given corresponding treatments by gavage and nebulization, while the normal and model groups received normal saline by gavage and nebulization. After the final stimulation, pathological changes in the lung and intestine tissues were observed using hematoxylin-eosin(HE) and periodic acid-Schiff(PAS) staining. Lung function was assessed by measuring the ratio of forced expiratory volume in the first second to forced vital capacity(FEV1/FVC), the ratio of the average flow rate at 25%-75% of forced vital capacity to foned vital capacity(FEV25%-75%/FVC), the peak expiratory flow(PEF), and pulmonary resistance(RL). The levels of IL-4, IL-5, IL-13, and TNF-α in serum, and sIgA in serum, intestinal, and bronchial mucosa were detected by enzyme-linked immunosorbent assay(ELISA). The expression of TAS2R14 protein in lung tissue was detected by Western blot(WB). The content of short-chain fatty acids(SCFAs) in rat feces was determined by gas chromatography-mass spectrometry(GC-MS). The effect of TAS2R14/TSLP on lipopolysaccharide(LPS)-induced inflammation in epithelial cells in the BCHs group was observed, and the expression of TAS2R14 and TSLP in cells was detected by WB. Compared with the normal group, the model group showed reduced water intake, diet, and body weight, increased infiltration of inflammatory cells in the lung and intestinal tissues, goblet cell hyperplasia, significantly decreased FEV1/FVC, FEV25%-75%/FVC, and PEF, and significantly increased RL. Moreover, serum levels of IL-4, IL-5, IL-13, and TNF-α were elevated, and sIgA levels in serum, intestine, and bronchial mucosa were significantly decreased. TAS2R14 expression in lung tissues was inhibited, and the content of acetic acid, propionic acid, and butyric acid in feces was significantly reduced. In the LPS group, TSLP expression increased, and TAS2R14 expression decreased. Compared with the model group, the general condition of rats in the SGMH and BCHs groups improved, with reduced infiltration of inflammatory cells and goblet cell hyperplasia in the lung and intestinal tissues. FEV1/FVC, FEV25%-75%/FVC, and PEF significantly increased, and RL significantly decreased. Serum levels of IL-4, IL-5, IL-13, and TNF-α decreased, while sIgA levels in serum, intestine, and bronchial mucosa significantly increased, and TAS2R14 expression was activated in lung and intestinal tissues. The content of acetic acid, propionic acid, and butyric acid in feces significantly increased. Compared with the model group, the BCHs group and the agonist group showed inhibited TSLP expression and increased TAS2R14 expression. The results showed that both SGMH and BCHs could reduce lung and intestinal inflammatory reactions, improve lung function, and regulate the content of intestinal SCFAs in asthmatic rats. There was no significant difference in TAS2R14 protein expression between the SGMH and BCHs groups, indicating that the clinical efficacy of BCHs may be related to the activation of the bitter receptor TAS2R14 and the regulation of immune inflammatory mediators in lung and intestinal epithelial cells.
Animals ; Drugs, Chinese Herbal/administration & dosage* ; Rats ; Rats, Sprague-Dawley ; Lung/metabolism* ; Asthma/metabolism* ; Cytokines/immunology* ; Male ; Receptors, G-Protein-Coupled/immunology* ; Epithelial Cells/metabolism* ; Thymic Stromal Lymphopoietin ; Immunoglobulin A, Secretory/genetics* ; Humans ; Cold Temperature

OBJECTIVES: To observe the role of miR-139-5p and Notch1 signaling pathway in regulation of homing of bone mesenchymal stem cells (BMSCs) of asthmatic rats. METHODS: Normal rat BMSCs were co-cultured with bronchial epithelial cells from normal or asthmatic rats, followed by transfection with miR-139-5p mimics or a negative control sequence. The changes in cell viability and cell cycle were analyzed, and the cellular expressions of CXCR4 and SDF-1 were detected using immunofluorescence staining. The changes of BMSC homing after the transfection were observed, and the expressions of Notch1, RBP-J, and Hes1 mRNAs and proteins and Th1/Th2 cytokines were detected with RT-qPCR, Western blotting or ELISA. RESULTS: The co-cultures of BMSCs and asthmatic bronchial epithelial cells showed significantly decreased expressions of miR-139-5p, IL-2 and IL-12 and increased expressions of CXCR4, SDF-1, IL-5, IL-9, Notch1, RBP-J, and Hes1. Transfection with miR-139-5p mimics significantly increased the expressions of miR-139-5p, IL-2, CXCR4 and SDF-1 and lowered the expression levels of IL-5, IL-9, Notch1, activated Notch1, and Hes1 in the co-cultured cells. Correlation analysis showed that BMSC homing was positively correlated with miR-139-5p and IL-12 and negatively correlated with IL-5 expression. The expression of CXCR4 was negatively correlated with activated Notch1, and SDF-1 was positively correlated with miR-139-5p but negatively correlated with Notch1 expression. CONCLUSIONS High expression of miR-139-5p promotes homing of BMSCs in asthma by targeting the Notch1 signaling pathway to regulate the expressions of Th1/Th2 cytokines, thereby alleviating airway inflammation.
Asthma/genetics* ; Animals ; Mesenchymal Stem Cells/cytology* ; MicroRNAs/metabolism* ; Rats ; Transcription Factor HES-1/genetics* ; Signal Transduction ; Receptor, Notch1/genetics* ; Immunoglobulin J Recombination Signal Sequence-Binding Protein/genetics* ; Receptors, CXCR4/genetics* ; Coculture Techniques ; Rats, Sprague-Dawley ; Chemokine CXCL12/genetics* ; Epithelial Cells/metabolism*

OBJECTIVES: To investigate the protective effect of the probiotic bacterium Streptococcus salivarius K12 (K12) against Mycoplasma pneumoniae (Mp) infection in mice. METHODS: Forty male BALB/c mice were randomized into normal control group, K12 treatment group, Mp infection group, and K12 pretreatment prior to Mp infection group. The probiotic K12 was administered daily by gavage for 14 days before Mp infection induced by intranasal instillation of Mp. Three days after Mp infection, the mice were euthanized for analysis of bronchoalveolar lavage fluid (BALF) cell counts and serum levels of secretory immunoglobulin A (sIgA), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6). RT-qPCR was performed to detect the P1 and community-acquired respiratory distress syndrome ( CARDS ) toxin of Mp in the lung tissues and the mRNA expressions of TNF-α, IL-6, chemokine 1 (CXCL1), matrix metalloproteinase 9 (MMP9), mucin 5ac (MUC5ac), collagen 3a1 (Col3a1), Toll-like receptor 2 (TLR2) and TLR4; the protein expressions of TLR2 and TLR4 in the lung tissue were detected using Western blotting. Pathological changes in the lung tissue and airway remodeling were examined with HE staining and AB/PAS staining. RESULTS: Compared with the Mp-infected mice with PBS treatment, the infected mice with K12 treatment showed significantly lowered mRNA levels of P1 and CARDS in the lung tissue and reduced white blood cell counts in the BALF (P<0.05). In spite of the absence of significant differences in serum levels of inflammatory factors between the two groups, the mRNA expressions of TNF‑α, IL-6, CXCL1, MMP9, MUC5ac and COL3A1 and the mRNA and protein levels of TLR2 and TLR4 in the lung tissues were significantly lower in K12-treated mice, in which AB/PAS staining showed obviously decreased mucus secretion. CONCLUSIONS K12 pretreatment can effectively reduce pulmonary inflammatory responses, improve airway remodeling and alleviate lung injury in Mp-infected mice.
Animals ; Mice ; Pneumonia, Mycoplasma/metabolism* ; Mice, Inbred BALB C ; Toll-Like Receptor 2/metabolism* ; Mycoplasma pneumoniae ; Male ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-6/metabolism* ; Lung/microbiology* ; Toll-Like Receptor 4/metabolism* ; Streptococcus salivarius ; Probiotics/administration & dosage* ; Bronchoalveolar Lavage Fluid ; Matrix Metalloproteinase 9/metabolism* ; Mucin 5AC/metabolism* ; Chemokine CXCL1/metabolism* ; Immunoglobulin A, Secretory/metabolism* ; Bacterial Toxins ; Bacterial Proteins