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

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 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

BACKGROUND: Epstein-Barr (EB) virus infection stimulates the production of vascular endothelial growth factor (VEGF), which contributes to the progression of angiogenesis. Angiogenesis plays an important role in the development of atherosclerosis. Since serum anti-early antigen EB virus IgG (EBV EA-IgG) titer is a sign of active EB virus infection, EBV EA-IgG titer could be associated with atherosclerosis. The number of minor (T) alleles in VEGF polymorphism rs3025039 has been reported to be inversely associated with serum VEGF concentration, suggesting that rs3025039 might have a strong influence on the association between EBV EA-IgG titer and atherosclerosis. By focusing on the role of VEGF in the development of atherosclerosis, this study aimed to investigate the association between active EB virus infection and atherosclerosis. METHODS: A cross-sectional study of 2,661 older Japanese individuals aged 60-89 years who participated in annual health check-ups during 2017-2019 was conducted. Logistic regression was used to evaluate the association between EBV EA-IgG titer and atherosclerosis in relation to rs3025039 genotype. The influence of rs3025039 (T) allele carrier status on the association between EBV EA-IgG titer and atherosclerosis was also evaluated by using logistic regression. RESULTS: Among rs3025039 CC-homozygotes, with the lowest EBV EA-IgG titer tertile as the reference, the multivariable odds ratio (95% confidence interval) was 1.11 (0.82, 1.50) for the medium tertile and 1.07 (0.78, 1.47) for the high tertile. Among rs3025039 (T) allele carriers, the corresponding values were 1.44 (0.88, 2.36) and 1.88 (1.15, 3.05), respectively. There was a significant interaction between rs3025039 (T) allele carrier status and the association between EBV EA-IgG titer and atherosclerosis (adjusted p = 0.0497). CONCLUSION EBV EA-IgG titer was significantly positively associated with atherosclerosis only among participants who are genetically less likely to have progressive angiogenesis. An angiogenesis-related genetic factor was revealed as a determinant of the association between EBV EA-IgG titer and atherosclerosis. These findings introduce a novel concept that could explain the association between viral infection and atherosclerosis.
Humans ; Aged ; Male ; Middle Aged ; Female ; Japan/epidemiology* ; Atherosclerosis/virology* ; Aged, 80 and over ; Vascular Endothelial Growth Factor A/genetics* ; Epstein-Barr Virus Infections/virology* ; Polymorphism, Single Nucleotide ; Cross-Sectional Studies ; Herpesvirus 4, Human ; Antigens, Viral/immunology* ; Antibodies, Viral/blood* ; Immunoglobulin G/blood* ; Genotype ; East Asian People

Objective:To investigate the clinical characteristics and major allergens of patients with pollen-food allergy syndrome（PFAS） and their correlation with the severity of symptoms, and to provide a basis for identifying high-risk patients, optimizing the allergen testing process and developing individualized dietary management strategies. Methods:The clinical data of 166 patients with PFAS admitted to our hospital from January 2021 to July 2023 were retrospectively analyzed. The clinical symptoms, pollen types and food allergy of the patients were analyzed by questionnaire survey and serum specific IgE detection. phi coefficient, Apriori algorithm modeling and multivariate logistic regression analysis were used to evaluate the association between allergen and symptom severity. Results:Artemisia pollen was the most common allergen in this area, with a positive rate of 96.39%. Peach and mango were the most common food allergens, which caused allergic reactions in 24.10% and 22.89% of patients, respectively. Oral mucosal symptoms were the main symptoms. Correlation analysis showed that there was a correlation between pollen allergens and allergenic food. Association rule analysis showed that when the patient was allergic to the combination of peanuts and trees, the probability of high severity of symptoms was 82.35%. Multivariate analysis showed that ragweed allergy was significantly positively correlated with the severity of PFAS symptoms. Conclusion:Artemisia pollen and related food allergens play an important role in the pathogenesis of PFAS. Association rule mining and network map analysis revealed direct associations between peanut and tree combination allergy and symptom severity, as well as potential links between other inhaled allergens and specific food allergies. Ragweed and peach allergy are independent risk factors for the aggravation of PFAS symptoms, which can be used as early warning indicators. These results help to improve the screening of high-risk patients and the construction of regional allergen databases.
Humans ; Food Hypersensitivity/immunology* ; Allergens/immunology* ; Retrospective Studies ; Pollen/immunology* ; Cross Reactions ; Immunoglobulin E/blood* ; Rhinitis, Allergic, Seasonal/immunology* ; Artemisia/immunology* ; Male ; Female ; Adult ; Prunus persica/immunology* ; Arachis/immunology* ; Middle Aged ; Surveys and Questionnaires ; Oral Allergy Syndrome

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

OBJECTIVE: To observe the clinical efficacy of combination therapy of wheat-grained sized cone moxibustion and point-to-point needle insertion with medical ozone penetrating injection for allergic rhinitis (AR) and its effect on inflammation-related indexes. METHODS: Thirty-one patients with persistent AR were enrolled. The patients received medical ozone injection at bilateral Yingxiang (LI20)-to-Shangyingxiang (EX-HN8), and wheat-grained sized cone moxibustion at Dazhui (GV14), twice a week (with a 3-day interval) for 4 consecutive weeks. The total nasal symptoms score (TNSS), total non-nasal symptom score (TNNSS), rhinoconjunctivitis quality of life questionnaire (RQLQ), and rhinitis control assessment test (RCAT) scores were evaluated before treatment, after treatment, and at the 8-week follow-up. Levels of eosinophil (EOS) count, immunoglobulin E (IgE), interleukin (IL)-4, IL-6, and IL-17 were measured before and after treatment. Clinical efficacy was evaluated after treatment, and the recurrence rate was assessed at follow-up. RESULTS: Compared with those before treatment, the TNSS, TNNSS, and RQLQ scores were decreased (P<0.05), while the RCAT score was increased (P<0.05) after treatment and at follow-up. There were no statistically significant differences in above indexes between the post-treatment and follow-up (P>0.05). After treatment, the whole blood EOS count and serum levels of IgE, IL-4, IL-6, and IL-17 were decreased compared with those before treatment (P<0.05). After treatment, 17 cases were markedly effective, 12 cases were effective, and 2 cases were ineffective, resulting in a total effective rate of 93.5%. At follow-up, 2 cases relapsed, and the recurrence rate was 6.9%. CONCLUSION Combination therapy of wheat-grained sized cone moxibustion and point-to-point needle insertion with medical ozone injection can improve AR symptoms, reduce the recurrence rate, and enhance the quality of life. The mechanism may be associated with the regulation of immune-related indexes.
Humans ; Female ; Male ; Moxibustion ; Adult ; Ozone/administration & dosage* ; Middle Aged ; Young Adult ; Acupuncture Points ; Adolescent ; Combined Modality Therapy ; Treatment Outcome ; Immunoglobulin E/blood* ; Rhinitis, Allergic/immunology* ; Interleukin-4/immunology*

OBJECTIVE: To investigate the effectiveness of tibial transverse transport (TTT) in treating Wagner grade 3-4 type 2 diabetic foot ulcers and analyze dynamic changes in immunoglobulin levels. METHODS: The clinical data of 68 patients with Wagner grade 3-4 type 2 diabetic foot ulcers treated with TTT between May 2022 and September 2023 was retrospectively analyzed. The cohort included 49 males and 19 females, aged 44-91 years (mean, 67.3 years), with 40 Wagner grade 3 and 28 grade 4 ulcers. The duration of type 2 diabetes ranged from 5 to 23 years, with an average of 10 years. The number of wound healing cases, healing time, amputation cases, death cases, and complications were observed and recorded. Serum samples were collected at 6 key time points [1 day before TTT and 3 days, 7 days (the first day of upward transverse transfer), 14 days (the first day of downward transverse transfer), 21 days (the first day after the end of transfer), 36 days (the first day after the removal of the transfer device)], and the serum immunoglobulin levels were detected by flow cytometry including immunoglobulin G (IgG), IgA, IgM, IgE, complement C3 (C3), C4, immunoglobulin light chain κ (KAP), immunoglobulin light chain λ (LAM). RESULTS: All the 68 patients were followed up 6 months. Postoperative pin tract infection occurred in 3 cases and incision infection in 2 cases. Amputation occurred in 5 patients (7.4%) at 59-103 days after operation, and 8 patients (11.8%) died at 49-77 days after operation; the wounds of the remaining 55 patients (80.9%) healed in 48-135 days, with an average of 80 days. There was no recurrence of ulcer, peri-osteotomy fracture, or local skin necrosis during follow-up. The serum immunoglobulin levels of 55 patients with wound healing showed that the levels of IgG and IgM decreased significantly on the 3rd and 7th day after operation compared with those before operation ( P<0.05), and gradually returned to the levels before operation after 14 days, and reached the peak on the 36th day. IgA levels continued to decrease with time, and there were significant differences at all time points when compared with those before operation ( P<0.05). The level of IgE significantly decreased at 21 days after operation compared with that before operation ( P<0.05), while it was higher at other time points than that before operation, but the difference was not significant ( P>0.05). The level of C3 showed a clear treatment-related increase, which was significantly higher on the 7th, 14th, and 21st days after operation than that before operation ( P<0.05), and the peak appeared on the 14th day. The change trend of C4 level was basically synchronous with that of C3, but the amplitude was smaller, and the difference was significant at 7 and 14 days after operation compared with that before operation ( P<0.05). There was no significant difference in KAP/LAM between different time points before and after operation ( P>0.05). CONCLUSION TTT can accelerate wound healing, effectively treat diabetic foot ulcer, and reduce amputation rate, and has definite effectiveness. The potential mechanisms of TTT in the treatment of diabetic foot ulcers include the dynamic regulation of IgG, IgA, IgM, and IgE levels to balance the process of inflammation and repair, and the periodic increase of C3 and C4 levels may promote tissue cleaning, angiogenesis, and anti-infection defense.
Humans ; Male ; Female ; Middle Aged ; Aged ; Diabetic Foot/immunology* ; Wound Healing ; Adult ; Retrospective Studies ; Aged, 80 and over ; Treatment Outcome ; Tibia/transplantation* ; Diabetes Mellitus, Type 2/complications* ; Amputation, Surgical ; Immunoglobulins/blood* ; Immunoglobulin G/blood*

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

Objective To explore the effects of S100 calcium-binding protein A9 (S100A9) gene knockout on the phenotype of systemic lupus erythematosus (SLE) in mice and to clarify the role of S100A9 in the pathogenesis of SLE. Methods Ten female C57BL/6 wild-type and S100A9 knockout (S100A9-KO ) mice were selected, with five wild-type and five S100A9-KO B6 mice receiving imiquimod (IMQ) cream to establish SLE mouse model. The other five wild-type and five S100A9-KO B6 mice were treated as control groups by wiping the skin of the right ear with a cotton swab. After 8 weeks, the mice were sacrificed. The serum was collected from each mouse to detect the levels of anti-double-stranded DNA (dsDNA) antibodies, immunoglobulin G (IgG), B cell activating factor (BAFF), and interleukin 6 (IL-6) using ELISA. The levels of serum creatinine were determined using a sarcosine oxidase method. Urine was collected to measure urinary protein concentration. Kidneys were collected and stained with hematoxylin and eosin (H&E) for evaluating histological changes. Results After IMQ treatment, the length and weight of spleen, levels of serum creatinine, anti-dsDNA antibodies, IgG, BAFF, IL-6, and urinary protein in the IMQ B6 group and IMQ S100A9-KO B6 group were significantly higher than those of the control groups. Lupus-like changes including increased glomerular volume and tubular epithelial swelling were observed in kidneys from the IMQ and IMQ S100A9-KO groups. However, compared with the IMQ B6 group, the IMQ S100A9-KO B6 group exhibited milder levels of serum and urine indicators as well as the lupus-like symptoms. Conclusion IMQ could induce lupus-like symptoms in both wild-type B6 mice and S100A9-KO B6 mice, but the lesions in S100A9 knockout mice are milder. Theses results suggested that S100A9 is involved in and promotes the pathogenesis of SLE.
Animals ; Lupus Erythematosus, Systemic/chemically induced* ; Female ; Calgranulin B/genetics* ; Mice, Knockout ; Mice, Inbred C57BL ; Phenotype ; Mice ; Interleukin-6/blood* ; Disease Models, Animal ; Antibodies, Antinuclear/blood* ; B-Cell Activating Factor/blood* ; Immunoglobulin G/blood* ; Kidney/pathology*