Based on the interleukin-17(IL-17) signaling pathway, this study explores the effect and mechanism of Bufei Decoction on Klebsiella pneumoniae pneumonia in rats. SD rats were randomly divided into the control group, model group, Bufei Decoction low-dose group(6.68 g·kg~(-1)·d~(-1)), Bufei Decoction high-dose group(13.36 g·kg~(-1)·d~(-1)), and dexamethasone group(1.04 mg·kg~(-1)·d~(-1)), with 10 rats in each group. A pneumonia model was established by tracheal drip injection of K. pneumoniae. After successful model establishment, the improvement in lung tissue damage was observed following drug administration. Core targets and signaling pathways were screened using transcriptomics techniques. Real-time fluorescence quantitative polymerase chain reaction was used to detect the mRNA expression of core targets interleukin-6(IL-6), interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and chemokine CXC ligand 6(CXCL6). Western blot was used to assess key proteins in the IL-17 signaling pathway, including interleukin-17A(IL-17A), nuclear transcription factor-κB activator 1(Act1), tumor necrosis factor receptor-associated factor 6(TRAF6), and downstream phosphorylated p38 mitogen-activated protein kinase(p-p38 MAPK), and phosphorylated nuclear factor-κB p65(p-NF-κB p65). Apoptosis of lung tissue cells was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling(TUNEL). The results showed that, compared with the control group, the model group exhibited significant pathological damage in lung tissue. The mRNA expression of IL-6, IL-1β, TNF-α, and CXCL6, as well as the protein levels of IL-17A, Act1, TRAF6, p-p38 MAPK/p38 MAPK, and p-NF-κB p65/NF-κB p65, were significantly increased, and the number of apoptotic cells was notably higher, indicating successful model establishment. Compared with the model group, both low-and high-dose groups of Bufei Decoction showed reduced pathological damage in lung tissue. The mRNA expression levels of IL-6, IL-1β, TNF-α, and CXCL6, and the protein levels of IL-17A, Act1, TRAF6, p-p38 MAPK/p38 MAPK, and p-NF-κB p65/NF-κB p65, were significantly decreased, with a significant reduction in apoptotic cells in the high-dose group. In conclusion, Bufei Decoction can effectively improve lung tissue damage and reduce inflammation in rats with K. pneumoniae. The mechanism may involve the regulation of the IL-17 signaling pathway and the reduction of apoptosis.
Animals ; Interleukin-17/metabolism* ; Drugs, Chinese Herbal/administration & dosage* ; Rats, Sprague-Dawley ; Signal Transduction/drug effects* ; Rats ; Male ; Klebsiella pneumoniae/physiology* ; Klebsiella Infections/immunology* ; Humans ; Lung/drug effects*

OBJECTIVES: To investigate the effect of interleukin-17 (IL-17) gene polymorphism on the susceptibility to cow's milk protein allergy (CMPA) in infants and its association with gut microbiota. METHODS: A prospective study was conducted involving 100 infants diagnosed with CMPA at the Women and Children's Hospital of Ningbo University from January 2022 to October 2024. A total of 100 healthy infants undergoing routine check-ups at the same hospital during the same period was enrolled as the control group. Medical information was obtained through the electronic medical record system. IL-17A (rs2275913) and IL-17F (rs1889570) polymorphisms were detected using polymerase chain reaction-restriction fragment length polymorphism method. Serum IL-17 levels were measured using enzyme-linked immunosorbent assay, and high-throughput sequencing was employed to analyze the relative abundance of Lactobacillus and Bifidobacterium. Multivariate logistic regression analysis was used to explore the influencing factors of CMPA occurrence in infants. RESULTS: The proportions of infants with a family history of allergy and those with vitamin D deficiency or insufficiency were significantly higher in the CMPA group compared to those in the control group (P<0.05). The distribution of IL-17F (rs1889570) genotypes showed significant differences between the CMPA and control groups (P<0.05), with the frequency of the A allele being significantly higher in the CMPA group (P<0.05). Multivariate logistic regression analysis revealed that a family history of allergy, vitamin D deficiency or insufficiency, and carrying the IL-17F (rs1889570) AA genotype were independent influencing factors for CMPA in infants (P<0.05). Infants in the CMPA group with the IL-17F (rs1889570) AA genotype had significantly higher serum IL-17 levels compared to those with AG/GG genotypes (P<0.05), while the relative abundance of Lactobacillus and Bifidobacterium was significantly lower (P<0.05). CONCLUSIONS IL-17F (rs1889570) gene polymorphism influences susceptibility to CMPA in infants, potentially through mechanisms involving IL-17 expression and the relative abundance of gut probiotics.
Humans ; Interleukin-17/genetics* ; Milk Hypersensitivity/microbiology* ; Female ; Infant ; Male ; Prospective Studies ; Genetic Predisposition to Disease ; Gastrointestinal Microbiome ; Polymorphism, Genetic ; Milk Proteins/immunology*

This study investigates the role of Interleukin 17 (IL-17) in exacerbating periapical lesions caused by Porphyromonas gingivalis (Pg) lipopolysaccharides (LPS) in the context of metabolic disease and its potential impact on glucose tolerance. Researchers developed a unique mouse model where mice were monocolonized with Pg to induce periapical lesions. After 1 month, they were fed a high-fat diet (HFD) for 2 months to simulate metabolic disease and oral microbiota dysbiosis. To explore the role of LPS from Pg, wild-type (WT) mice were challenged with purified LPS from Porphyromonas gingivalis, as well as with LPS-depleted and non-depleted Pg bacteria; IL-17 knockout (KO) mice were also included to assess the role of IL-17 signaling. The impact on bone lysis, periapical injury, glucose intolerance, and immune response was assessed. Results showed that in WT mice, the presence of LPS significantly worsened bone lysis, Th17 cell recruitment, and periapical injury. IL-17 KO mice exhibited reduced bone loss, glucose intolerance, and immune cell infiltration. Additionally, inflammatory markers in adipose tissue were lower in IL-17 KO mice, despite increased dysbiosis. The findings suggest that IL-17 plays a critical role in amplifying Pg-induced periapical lesions and systemic metabolic disturbances. Targeting IL-17 recruitment could offer a novel approach to improving glycemic control and reducing type 2 diabetes (T2D) risk in individuals with periapical disease.
Animals ; Porphyromonas gingivalis/immunology* ; Th17 Cells/immunology* ; Lipopolysaccharides/immunology* ; Mice ; Glucose Intolerance/microbiology* ; Interleukin-17/metabolism* ; Mice, Knockout ; Mice, Inbred C57BL ; Disease Models, Animal ; Diet, High-Fat ; Periapical Diseases/microbiology* ; Male ; Dysbiosis

Andrographolide sulfonate (AS) is a sulfonated derivative of andrographolide extracted from Andrographis paniculata (Burm.f.) Nees, and has been approved for several decades in China. The present study aimed to investigate the novel therapeutic application and possible mechanisms of AS in the treatment of rheumatoid arthritis. Results indicated that administration of AS by injection or gavage significantly reduced the paw swelling, improved body weights, and attenuated pathological changes in joints of rats with adjuvant-induced arthritis. Additionally, the levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and IL-1β in the serum and ankle joints were reduced. Bioinformatics analysis, along with the spleen index and measurements of IL-17 and IL-10 levels, suggested a potential relationship between AS and Th17 cells under arthritic conditions. In vitro, AS was shown to block Th17 cell differentiation, as evidenced by the reduced percentages of CD4⁺ IL-17A⁺ T cells and decreased expression levels of RORγt, IL-17A, IL-17F, IL-21, and IL-22, without affecting the cell viability and apoptosis. This effect was attributed to the limited glycolysis, as indicated by metabolomics analysis, reduced glucose uptake, and pH measurements. Further investigation revealed that AS might bind to hexokinase2 (HK2) to down-regulate the protein levels of HK2 but not glyceraldehyde-3-phosphate dehydrogenase (GAPDH) or pyruvate kinase M2 (PKM2), and overexpression of HK2 reversed the inhibition of AS on Th17 cell differentiation. Furthermore, AS impaired the activation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signals in vivo and in vitro, which was abolished by the addition of lactate. In conclusion, AS significantly improved adjuvant-induced arthritis (AIA) in rats by inhibiting glycolysis-mediated activation of PI3K/AKT to restrain Th17 cell differentiation.
Animals ; Th17 Cells/immunology* ; Diterpenes/pharmacology* ; Arthritis, Rheumatoid/metabolism* ; Proto-Oncogene Proteins c-akt/immunology* ; Glycolysis/drug effects* ; Cell Differentiation/drug effects* ; Phosphatidylinositol 3-Kinases/genetics* ; Rats ; Male ; Rats, Sprague-Dawley ; Humans ; Andrographis paniculata/chemistry* ; Arthritis, Experimental/drug therapy* ; Interleukin-17/immunology* ; Signal Transduction/drug effects*

Spinal cord injury (SCI) causes motor, sensory, and autonomic dysfunctions. The gut microbiome has an important role in SCI, while short-chain fatty acids (SCFAs) are one of the main bioactive mediators of microbiota. In the present study, we explored the effects of oral administration of exogenous SCFAs on the recovery of locomotor function and tissue repair in SCI. Allen's method was utilized to establish an SCI model in Sprague-Dawley (SD) rats. The animals received water containing a mixture of 150 mmol/L SCFAs after SCI. After 21 d of treatment, the Basso, Beattie, and Bresnahan (BBB) score increased, the regularity index improved, and the base of support (BOS) value declined. Spinal cord tissue inflammatory infiltration was alleviated, the spinal cord necrosis cavity was reduced, and the numbers of motor neurons and Nissl bodies were elevated. Enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction (qPCR), and immunohistochemistry assay revealed that the expression of interleukin (IL)‍-10 increased and that of IL-17 decreased in the spinal cord. SCFAs promoted gut homeostasis, induced intestinal T cells to shift toward an anti-inflammatory phenotype, and promoted regulatory T (Treg) cells to secrete IL-10, affecting Treg cells and IL-17⁺ γδ T cells in the spinal cord. Furthermore, we observed that Treg cells migrated from the gut to the spinal cord region after SCI. The above findings confirm that SCFAs can regulate Treg cells in the gut and affect the balance of Treg and IL-17⁺ γδ T cells in the spinal cord, which inhibits the inflammatory response and promotes the motor function in SCI rats. Our findings suggest that there is a relationship among gut, spinal cord, and immune cells, and the "gut-spinal cord-immune" axis may be one of the mechanisms regulating neural repair after SCI.
Animals ; Rats ; Interleukin-17 ; Rats, Sprague-Dawley ; Recovery of Function ; Spinal Cord Injuries/drug therapy* ; T-Lymphocytes, Regulatory ; Receptors, Antigen, T-Cell, gamma-delta/immunology*

The γδ T cells are unconventional lymphocytes that function in both innate and adaptive immune responses against various intracellular and infectious stresses. The γδ T cells can be exploited as cancer-killing effector cells since γδ TCRs recognize MHC-like molecules and growth factor receptors that are upregulated in cancer cells, and γδ T cells can differentiate into cytotoxic effector cells. However, γδ T cells may also promote tumor progression by secreting IL-17 or other cytokines. Therefore, it is essential to understand how the differentiation and homeostasis of γδ T cells are regulated and whether distinct γδ T cell subsets have different functions. Human γδ T cells are classified into Vδ2 and non-Vδ2 γδ T cells. The majority of Vδ2 γδ T cells are Vγ9δ2 T cells that recognize pyrophosphorylated isoprenoids generated by the dysregulated mevalonate pathway. In contrast, Vδ1 T cells expand from initially diverse TCR repertoire in patients with infectious diseases and cancers. The ligands of Vδ1 T cells are diverse and include the growth factor receptors such as endothelial protein C receptor. Both Vδ1 and Vδ2 γδ T cells are implicated to have immunotherapeutic potentials for cancers, but the detailed elucidation of the distinct characteristics of 2 populations will be required to enhance the immunotherapeutic potential of γδ T cells. Here, we summarize recent progress regarding cancer immunology of human γδ T cells, including their development, heterogeneity, and plasticity, the putative mechanisms underlying ligand recognition and activation, and their dual effects on tumor progression in the tumor microenvironment.
Allergy and Immunology ; Communicable Diseases ; Cytokines ; Homeostasis ; Humans ; Interleukin-17 ; Ligands ; Lymphocytes ; Mevalonic Acid ; Plastics ; Population Characteristics ; Protein C ; Receptors, Antigen, T-Cell, gamma-delta ; Receptors, Growth Factor ; T-Lymphocyte Subsets ; T-Lymphocytes ; Terpenes ; Tumor Microenvironment

BACKGROUND: As a potent pro-inflammatory cytokine of the interleukin (IL)-1 family, IL-18 was elevated in early active and progressive plaque-type psoriatic lesions and that serum or plasma levels of IL-18 correlated with the Psoriasis Area and Severity Index (PASI). Although results from previous studies have established that IL-18 may aggravate psoriatic inflammation, the mechanisms of this process remain unknown. In this study, IL-18 knock out (KO) mice and wild-type (WT) mice were used to investigate the effects of IL-18 within a mouse model of psoriasis. METHODS: WT and IL-18 KO mice were divided into four groups, including imiquimod (IMQ)-treated IL-18 KO group (n = 11) and WT group (n = 13) as well as their respectively gene-matched control mice (receiving vaseline; n = 12). PASI scores were used to evaluate psoriatic lesions in IMQ-treated mice. Pathological features and dermal cellular infiltration were investigated by hematoxylin and eosin staining. The levels of psoriasis-related cytokines including IL-23, IL-17, IL-12, IL-1β, IFNγ, IL-15, IL-27, and IL-4 were tested by real-time polymerase chain reaction (PCR). The protein level of IL-1β, IL-27, CXCL1, and Ly6 g were investigated by immunohistochemistry (IHC). RESULTS: Acanthosis (98.46 ± 14.12 vs. 222.68 ± 71.10 μm, P < 0.01) and dermal cell infiltration (572.25 ± 47.45 vs. 762.47 ± 59.59 cells/field, P < 0.01) were significantly milder in IMQ-induced IL-18 KO mice compared with that in WT mice. IMQ-induced IL-18 KO mice manifested larger areas of Munro microabscesses (11,467.83 ± 5112.09 vs. 4093.19 ± 2591.88 μm, P < 0.01) and scales (100,935.24 ± 41,167.77 vs. 41,604.41 ± 14,184.10 μm, P < 0.01) as compared with WT mice. In skin lesions of IL-18 KO mice, the expressions of IL-1β, IL-4, and IL-27 were all significantly upregulated but IL-17 was decreased. Histologically, strong positive signals of Ly6g were observed within the epidermis of IL-18 KO mice but expressions of CXCL1 were decreased. CONCLUSIONS IL-18 may exacerbate prominent inflammation and influence pathological features in IMQ-induced mouse model of psoriasis. IL-18 may upregulate pro-inflammatory cytokines and reduce protective cytokines, thus aggravating psoriatic inflammation. In addition, IL-18 may be involved in the formation of Munro microabscesses and scales.
Animals ; Chemokine CXCL1 ; metabolism ; Cytokines ; metabolism ; Disease Models, Animal ; Imiquimod ; toxicity ; Interleukin-17 ; metabolism ; Interleukin-18 ; metabolism ; Mice ; Mice, Knockout ; Psoriasis ; chemically induced ; genetics ; metabolism ; Skin ; immunology ; metabolism

BACKGROUND: Recent studies have reported that glucosamine (GlcN) showed therapeutic effects in allergic diseases such as asthma and rhinitis, and its mechanisms include the suppression of T helper type 2 immune responses and the nuclear factor-κB pathway. OBJECTIVE: We aimed to investigate the effect of GlcN on atopic dermatitis (AD) in an animal model. METHODS: Twenty-five BALB/c mice were divided into five groups (groups A~E). Group A was the phosphate-buffered saline (PBS)-treated group without AD induction. Group B was the PBS control group with AD induction. Groups C to E were the AD induction groups, which were treated with three different doses of GlcN (10 mg, 20 mg, and 40 mg, respectively). Histopathological examination was performed after GlcN administration. Interleukin (IL)-4, IL-13, and IL-17 cytokine levels were measured by enzyme-linked immunosorbent assay using skin biopsy specimens. Serum total immunoglobulin E (IgE) concentrations were measured before and after administration with GlcN or PBS. RESULTS: Clinical dermatitis scores decreased with increasing GlcN dose (p<0.001). Concentrations of tissue IL-13 and IL-17 decreased after GlcN administration (each group: p=0.002 and p<0.001, respectively), but the concentrations of tissue IL-4 did not show differences across groups. Serum IgE levels tended to be lower after GlcN administration (p=0.004). Histopathological scores were not significantly different among groups B~E (p=0.394). CONCLUSION: GlcN improved AD symptoms and decreased tissue IL-13, IL-17, and serum total IgE levels in an animal model.
Allergy and Immunology ; Animals ; Anti-Allergic Agents ; Asthma ; Biopsy ; Dermatitis ; Dermatitis, Atopic ; Enzyme-Linked Immunosorbent Assay ; Glucosamine ; Immunoglobulin E ; Immunoglobulins ; Interleukin-13 ; Interleukin-17 ; Interleukin-4 ; Interleukins ; Mice ; Models, Animal ; Rhinitis ; Skin ; Therapeutic Uses

OBJECTIVETo observe the effects of bacterial lysates (OM-85BV) and all trans-retinoic acid (ATRA) on airway inflammation in asthmatic mice, and to investigate the immunoregulatory mechanism of OM-85BV and ATRA for airway inflammation in asthmatic mice.

METHODSForty female BALB/c mice were randomly divided into five groups: normal control, model, OM-85BV, ATRA, and OM-85BV+ATRA. A bronchial asthma model was established by intraperitoneal injection of ovalbumin (OVA) for sensitization and aerosol challenge in all mice except those in the normal control group. On days 25-34, before aerosol challenge, the model, OM-85BV, ATRA, and OM-85BV+ATRA groups were given normal saline, OM-85BV, ATRA, and OM-85BV+ATRA respectively by gavage. Normal saline was used instead for sensitization, challenge, and pretreatment before challenge in the normal control group. These mice were anesthetized and dissected at 24-48 hours after the final challenge. Bronchoalveolar lavage fluid (BALF) was collected from the right lung to measure the levels of interleukin-10 (IL-10) and interleukin-17 (IL-17) by ELISA. The left lung was collected to observe histopathological changes by hematoxylin-eosin staining. The relative expression of ROR-γT mRNA was measured by quantitative real-time PCR.

RESULTSCompared with the normal control group, the model group showed contraction of the bronchial cavity, increased bronchial secretions, and a large number of infiltrating inflammatory cells around the bronchi and alveolar walls, as well as a significantly reduced level of IL-10 (P<0.05) and significantly increased levels of IL-17 and ROR-γT mRNA (P<0.05). Compared with the model group, the OM-85BV, ATRA, and OM-85BV+ATRA groups showed a significant reduction in infiltrating inflammatory cells around the bronchi and alveolar walls; the OM-85BV group showed a significant increase in the level of IL-10 in BALF (P<0.05) and significant reductions in the levels of IL-17 and ROR-γT mRNA (P<0.05); the ATRA group showed significant reductions in the levels of IL-17 and ROR-γT mRNA (P<0.05). Compared with the OM-85BV group, the OM-85BV+ATRA group had significantly increased relative expression of ROR-γT mRNA (P<0.05). Compared with the ATRA group, the OM-85BV+ATRA group had significantly increased levels of IL-10 and IL-17 in BALF (P<0.05).

CONCLUSIONSBoth OM-85BV and ATRA can reduce respiratory inflammation in asthmatic mice. However, a combination of the two drugs does not have a better effect than them used alone.

Animals ; Asthma ; drug therapy ; genetics ; immunology ; Cell Extracts ; administration & dosage ; Female ; Humans ; Interleukin-10 ; genetics ; immunology ; Interleukin-17 ; genetics ; immunology ; Lung ; drug effects ; immunology ; Mice ; Mice, Inbred BALB C ; Tretinoin ; administration & dosage

OBJECTIVETo investigate the percentages of peripheral blood γδ T cells and regulatory T cells (Treg) and the expression of associated cytokines, interleukin 17 (IL-17) and transforming growth factor-β1 (TGF-β1), in infants with human cytomegalovirus (HCMV) infection.

METHODSTwenty-two infants with HCMV infection (HCMV group) and 22 healthy infants who underwent physical examination (control group) were enrolled in this study. The percentages of peripheral blood γδ T cells and Treg cells were determined by flow cytometry. The levels of IL-17 and TGF-β1 in plasma were measured using ELISA.

RESULTSCompared with the control group, the HCMV group had significantly higher percentage of γδ T cells and IL-17 level (P<0.01) and significantly lower percentage of Treg cells and TGF-β1 level (P<0.01). In the HCMV group, the percentage of γδ T cells was negatively correlated with the percentage of Treg cells and TGF-β1 level (P<0.05), but positively correlated with IL-17 level (P<0.05); the percentage of Treg cells was positively correlated with TGF-β1 level (P<0.05), but negatively correlated with IL-17 level (P<0.05); there was no correlation between IL-17 level and TGF-β1 level (P>0.05).

CONCLUSIONSThere is an imbalance between γδ T cells and Treg cells in the peripheral blood of infants with HCMV infection, and γδ T cells may be involved in the secretion of IL-17.

Cytokines ; blood ; Cytomegalovirus Infections ; immunology ; Female ; Humans ; Infant ; Interleukin-17 ; blood ; Male ; Receptors, Antigen, T-Cell, gamma-delta ; analysis ; T-Lymphocytes, Regulatory ; immunology ; Transforming Growth Factor beta1 ; blood