Recently, photodynamic therapy (PDT) has gained considerable attention as a promising therapeutic approach for the treatment of psoriasis. Unfortunately, the activation of high mobility group box 1 protein (HMGB1) by PDT triggers innate and adaptive immune responses, which exacerbate skin inflammation. Herein, we combined glycyrrhizic acid (GA), a natural anti-inflammatory compound and immunomodulator derived from the herb Glycyrrhiza uralensis Fisch., with PDT actuated by the photosensitizer chlorin e6 (Ce6) by co-loading them in GA-based lipid nanoparticles coated with a catechol-modified quaternary chitosan salt (GC NPs/QCS-C). GC NPs/QCS-C exhibited high drug loading efficacy, uniform size distribution, an ideal topical adhesive property, enhanced skin retention and penetration in psoriasis-like lesions, and high intracellular uptake in epidermal cells compared with the counterparts. Subsequently, the transdermal administration of GC NPs/QCS-C followed by near-infrared laser radiation in an imiquimod-induced psoriasis-like mouse model significantly ameliorated psoriasis symptoms, promoted the apoptosis of hyperproliferative epidermal cells, and alleviated the inflammatory cascade. The significant therapeutic outcomes of GC NPs/QCS-C were attributed to the synergistic effects of GA and PDT on modulating immune cell recruitment and inhibiting dendritic cell maturation. Our results demonstrated that the topical bio-adhesive nanosystem that combines GA and Ce6 offers a synergistic chemo-phototherapeutic strategy for psoriasis treatment.

Extensive epigenetic reprogramming involves in memory CD8+ T-cell differentiation. The elaborate epigenetic rewiring underlying the heterogeneous functional states of CD8+ T cells remains hidden. Here, we profile single-cell chromatin accessibility and map enhancer-promoter interactomes to characterize the differentiation trajectory of memory CD8+ T cells. We reveal that under distinct epigenetic regulations, the early activated CD8+ T cells divergently originated for short-lived effector and memory precursor effector cells. We also uncover a defined epigenetic rewiring leading to the conversion from effector memory to central memory cells during memory formation. Additionally, we illustrate chromatin regulatory mechanisms underlying long-lasting versus transient transcription regulation during memory differentiation. Finally, we confirm the essential roles of Sox4 and Nrf2 in developing memory precursor effector and effector memory cells, respectively, and validate cell state-specific enhancers in regulating Il7r using CRISPR-Cas9. Our data pave the way for understanding the mechanism underlying epigenetic memory formation in CD8+ T-cell differentiation.
CD8-Positive T-Lymphocytes/metabolism* ; Cell Differentiation ; Chromatin/immunology* ; Animals ; Mice ; Immunologic Memory ; Epigenesis, Genetic ; SOXC Transcription Factors/immunology* ; NF-E2-Related Factor 2/immunology* ; Mice, Inbred C57BL ; Gene Regulatory Networks ; Enhancer Elements, Genetic

OBJECTIVE: To investigate the role and mechanism of the cyclic guanosine monophosphate-adenosine monophosphate synthase/stimulator of interferon gene (cGAS/STING) pathway in oleic acid-induced acute lung injury (ALI) in mice. METHODS: Male wild-type C57BL/6J mice were randomly divided into five groups (each n = 10): normal control group, ALI model group, and 5, 50, 500 μg/kg inhibitor pretreatment groups. The ALI model was established by tail vein injection of oleic acid (7 mL/kg), while the normal control group received no intervention. The inhibitor pretreatment groups were intraperitoneally injected with the corresponding doses of cGAS inhibitor RU.521 respectively 1 hour before modeling. At 24 hours post-modeling, blood was collected, and mice were sacrificed. Lung tissue pathological changes were observed under light microscopy after hematoxylin-eosin (HE) staining, and pathological scores were assessed. Western blotting was used to detect the protein expressions of cGAS, STING, phosphorylated TANK-binding kinase 1 (p-TBK1), phosphorylated interferon regulatory factor 3 (p-IRF3), and phosphorylated nuclear factor-κB p65 (p-NF-κB p65) in lung tissue. Immunohistochemistry was performed to observe STING and p-NF-κB positive expressions in lung tissue. Serum interferon-β (IFN-β) levels were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared with the normal control group, the ALI model group exhibited significant focal alveolar thickening, intra-alveolar hemorrhage, pulmonary capillary congestion, and neutrophil infiltration in the pulmonary interstitium and alveoli, along with markedly increased pathological scores (10.33±0.58 vs. 1.33±0.58, P < 0.05). Protein expressions of cGAS, STING, p-TBK1, p-IRF3, and p-NF-κB p65 in lung tissue significantly increased [cGAS protein (cGAS/β-actin): 1.24±0.02 vs. 0.56±0.02, STING protein (STING/β-actin): 1.27±0.01 vs. 0.55±0.01, p-TBK1 protin (p-TBK1/β-actin): 1.34±0.03 vs. 0.22±0.01, p-IRF3 protein (p-IRF3/β-actin): 1.23±0.02 vs. 0.36±0.01, p-NF-κB p65 protein (p-NF-κB p65/β-actin): 1.30±0.02 vs. 0.53±0.02, all P < 0.05], positive expressions of STING and p-NF-κB in lung tissue were significantly elevated [STING (A value): 0.51±0.03 vs. 0.30±0.07, p-NF-κB (A value): 0.57±0.05 vs. 0.31±0.03, both P < 0.05], and serum IFN-β levels were also significantly higher (ng/L: 256.02±3.84 vs. 64.15±1.17, P < 0.05). The cGAS inhibitor pretreatment groups showed restored alveolar structural integrity, reduced inflammatory cell infiltration, and decreased hemorrhage area, along with dose-dependent lower pathological scores as well as the protein expressions of cGAS, STING, p-TBK1, p-IRF3 and p-NF-κB p65 in lung tissue, with significant differences between the 500 μg/kg inhibitor group and ALI model group [pathological score: 2.67±0.58 vs. 10.33±0.58, cGAS protein (cGAS/β-actin): 0.56±0.03 vs. 1.24±0.02, STING protein (STING/β-actin): 0.67±0.03 vs. 1.27±0.01, p-TBK1 protein (p-TBK1/β-actin): 0.28±0.01 vs. 1.34±0.03, p-IRF3 protein (p-IRF3/β-actin): 0.32±0.01 vs. 1.23±0.02, p-NF-κB p65 protein (p-NF-κB p65/β-actin): 0.63±0.01 vs. 1.30±0.02, all P < 0.05]. Compared with the ALI model group, positive expressions of STING and p-NF-κB in lung tissue were significantly reduced in the 500 μg/kg inhibitor group [STING (A value): 0.40±0.01 vs. 0.51±0.03, p-NF-κB (A value): 0.43±0.02 vs. 0.57±0.05, both P < 0.05], and serum IFN-β levels were also markedly reduced (ng/L: 150.03±6.19 vs. 256.02±3.84, P < 0.05). CONCLUSIONS The cGAS/STING pathway is activated in oleic acid-induced ALI, leading to exacerbated inflammatory responses and increased lung damage. RU.521 can inhibit cGAS, thereby down-regulating the expression of pathway proteins and cytokines, and providing protection to lung tissue.
Animals ; Acute Lung Injury/chemically induced* ; Male ; Nucleotidyltransferases/metabolism* ; Mice ; Signal Transduction ; Mice, Inbred C57BL ; Membrane Proteins/metabolism* ; Oleic Acid/adverse effects* ; Transcription Factor RelA/metabolism* ; Lung/pathology* ; Interferon Regulatory Factor-3/metabolism* ; Disease Models, Animal

Objective:To investigate whether repeated tirofiban injections can continuously inhibit platelet aggregation in the arterial duct and affect its closure in neonatal canines.Methods:Four 24-month-old pregnant beagles underwent cesarean sections in two batches (two dogs per batch) 1-2 days before the expected delivery date at the Xuzhou Medical University Animal Experiment Center. The first litter of 21 neonates served as the control group (receiving 10 ml/kg normal saline) and were randomly divided into 1-h ( n=7, injected immediately after birth), 4-h ( n=7, injected at 0 h and 2 h after birth), and 12-h subgroups ( n=7, injected at 0 h, 2 h, 4 h, 6 h, 8 h, and 10 h after birth). The second litter of 18 neonates served as the experimental group (receiving 10 ml/kg tirofiban) with identical subgroup assignments ( n=6 per subgroup). Echocardiography was performed at 1 h, 4 h, and 12 h after birth to measure arterial duct inner diameter, maximum shunt velocity, and left atrial diameter/aortic root diameter (LA/Ao) ratio. Plasma platelet-derived growth factor (PDGF) was detected by enzyme-linked immunosorbent assay, while platelet membrane glycoprotein Ⅱb-Ⅲa in the arterial duct was assessed by Western blot and immunohistochemistry. Data were analyzed using t-tests, one-way ANOVA, Chi square tests, or Fisher's exact test. Results:No significant bleeding tendency occurred in either group. Two control neonates (one each in the 4-h and 12-h subgroups) died. In both control and experimental 1-h subgroups, all arterial ducts remained open, with no significant differences in ductal diameter, shunt velocity, or LA/Ao between groups (all P>0.05). In the 4-h subgroups, all experimental neonates had patent ducts arteriosus, while two controls exhibited closure; the experimental group had larger ductal diameters [(1.05±0.05) vs. (0.55±0.44) mm, t=－2.75, P<0.05)] and higher LA/Ao ratios (1.31±0.09 vs. 1.14±0.03, t=－4.90, P<0.05), but lower maximum shunt velocities [(107.06±17.47) vs. (153.74±12.78) cm/s, t=4.54, P=0.002). In the 12-h subgroups, all the controls had closed arterial ducts, while four of six experimental neonates exhibited closure, though the difference in closure rate was not statistically significant (6/6 vs. 4/6, Fisher's exact test, P=0.455). Plasma PDGF and glycoprotein Ⅱb-Ⅲa levels did not differ between two 1-h subgroups (all P>0.05). However, the 4-h and 12-h experimental subgroups showed lower PDGF levels [(373.5±13.1) vs. (880.3±80.2) pg/ml, t=10.81; (356.7±35.0) vs. (1 111.2±125.3) pg/ml, t=9.74; both P<0.05] and reduced glycoprotein Ⅱb-Ⅲa expression (0.32±0.07 vs. 0.80±0.23, t=3.29; 0.42±0.07 vs. 0.92±0.26, t=3.24; both P<0.05) compared to controls. Conclusion:Repeated tirofiban injections sustainably inhibit platelet aggregation in the arterial duct of neonatal canines and delay ductal closure, suggesting that intraductal platelet aggregation may be one factor influencing this process.

Objective:To investigate the clinical efficacy of strengthening the spleen to nourish the lung in treating stable chronic obstructive pulmonary disease (COPD) with lung and spleen qi deficiency complicated by sarcopenia. Methods:This study was designed as a prospective study. A total of 65 patients with stable COPD and sarcopenia who received treatment at Kunshan Hospital of Chinese Medicine from January 2021 to December 2021 were included in the study. They were randomly divided into a control group and an observation group using the random number table method. The control group ( n = 34) was treated with conventional therapy, while the observation group ( n = 31) was treated with Shenling Baizhu Powder, a traditional Chinese medication based on the principle of strengthening the spleen to nourish the lung, in addition to the conventional therapy given to the control group. Both groups were treated for 1 month. Traditional Chinese medicine syndrome score, pulmonary function, grip strength, walking speed, albumin and prealbumin levels were compared between the two groups. Results:After treatment, the scores of all traditional Chinese medicine syndromes in the observation group were significantly lower than those in the control group (all P < 0.05). Compared with the control group, the levels of forced expiratory volume in the first second (FEV 1)[(1.51 ± 0.27) L vs. (1.32 ± 0.20) L, t = 3.11, P < 0.001 ] and FEV 1/forced vital capacity (FVC) [(57.20 ± 8.41)% vs. (52.89 ± 5.66)%, t = 2.30, P = 0.025] were significantly higher in the observation group. Compared with before treatment, gait speed [(1.07 ± 0.27) m/s vs. (0.90 ± 0.30) m/s, t = 7.66, P < 0.001], grip strength [(20.62 ± 5.07) kg vs. (19.42 ± 5.78) kg, t = 3.55, P < 0.001], albumin [(231.38 ± 49.40) g/L vs. (200.26 ± 65.87) g/L, t = 3.70, P < 0.001] and prealbumin [(39.53 ± 3.45) g/L vs. (35.81 ± 4.46) g/L, t = 4.08, P < 0.001] levels in the observation group were significantly increased after treatment. There were no significant differences in gait speed, grip strength, albumin, and prealbumin levels in the control group before and after treatment (all P > 0.05). Conclusions:The method of strengthening the spleen to nourish the lung shows good clinical efficacy in treating stable COPD with lung and spleen deficiency complicated by sarcopenia, and it has great potential for broader application.

Objective:To investigate whether repeated tirofiban injections can continuously inhibit platelet aggregation in the arterial duct and affect its closure in neonatal canines.Methods:Four 24-month-old pregnant beagles underwent cesarean sections in two batches (two dogs per batch) 1-2 days before the expected delivery date at the Xuzhou Medical University Animal Experiment Center. The first litter of 21 neonates served as the control group (receiving 10 ml/kg normal saline) and were randomly divided into 1-h ( n=7, injected immediately after birth), 4-h ( n=7, injected at 0 h and 2 h after birth), and 12-h subgroups ( n=7, injected at 0 h, 2 h, 4 h, 6 h, 8 h, and 10 h after birth). The second litter of 18 neonates served as the experimental group (receiving 10 ml/kg tirofiban) with identical subgroup assignments ( n=6 per subgroup). Echocardiography was performed at 1 h, 4 h, and 12 h after birth to measure arterial duct inner diameter, maximum shunt velocity, and left atrial diameter/aortic root diameter (LA/Ao) ratio. Plasma platelet-derived growth factor (PDGF) was detected by enzyme-linked immunosorbent assay, while platelet membrane glycoprotein Ⅱb-Ⅲa in the arterial duct was assessed by Western blot and immunohistochemistry. Data were analyzed using t-tests, one-way ANOVA, Chi square tests, or Fisher's exact test. Results:No significant bleeding tendency occurred in either group. Two control neonates (one each in the 4-h and 12-h subgroups) died. In both control and experimental 1-h subgroups, all arterial ducts remained open, with no significant differences in ductal diameter, shunt velocity, or LA/Ao between groups (all P>0.05). In the 4-h subgroups, all experimental neonates had patent ducts arteriosus, while two controls exhibited closure; the experimental group had larger ductal diameters [(1.05±0.05) vs. (0.55±0.44) mm, t=－2.75, P<0.05)] and higher LA/Ao ratios (1.31±0.09 vs. 1.14±0.03, t=－4.90, P<0.05), but lower maximum shunt velocities [(107.06±17.47) vs. (153.74±12.78) cm/s, t=4.54, P=0.002). In the 12-h subgroups, all the controls had closed arterial ducts, while four of six experimental neonates exhibited closure, though the difference in closure rate was not statistically significant (6/6 vs. 4/6, Fisher's exact test, P=0.455). Plasma PDGF and glycoprotein Ⅱb-Ⅲa levels did not differ between two 1-h subgroups (all P>0.05). However, the 4-h and 12-h experimental subgroups showed lower PDGF levels [(373.5±13.1) vs. (880.3±80.2) pg/ml, t=10.81; (356.7±35.0) vs. (1 111.2±125.3) pg/ml, t=9.74; both P<0.05] and reduced glycoprotein Ⅱb-Ⅲa expression (0.32±0.07 vs. 0.80±0.23, t=3.29; 0.42±0.07 vs. 0.92±0.26, t=3.24; both P<0.05) compared to controls. Conclusion:Repeated tirofiban injections sustainably inhibit platelet aggregation in the arterial duct of neonatal canines and delay ductal closure, suggesting that intraductal platelet aggregation may be one factor influencing this process.

Objective:To investigate the clinical efficacy of strengthening the spleen to nourish the lung in treating stable chronic obstructive pulmonary disease (COPD) with lung and spleen qi deficiency complicated by sarcopenia. Methods:This study was designed as a prospective study. A total of 65 patients with stable COPD and sarcopenia who received treatment at Kunshan Hospital of Chinese Medicine from January 2021 to December 2021 were included in the study. They were randomly divided into a control group and an observation group using the random number table method. The control group ( n = 34) was treated with conventional therapy, while the observation group ( n = 31) was treated with Shenling Baizhu Powder, a traditional Chinese medication based on the principle of strengthening the spleen to nourish the lung, in addition to the conventional therapy given to the control group. Both groups were treated for 1 month. Traditional Chinese medicine syndrome score, pulmonary function, grip strength, walking speed, albumin and prealbumin levels were compared between the two groups. Results:After treatment, the scores of all traditional Chinese medicine syndromes in the observation group were significantly lower than those in the control group (all P < 0.05). Compared with the control group, the levels of forced expiratory volume in the first second (FEV 1)[(1.51 ± 0.27) L vs. (1.32 ± 0.20) L, t = 3.11, P < 0.001 ] and FEV 1/forced vital capacity (FVC) [(57.20 ± 8.41)% vs. (52.89 ± 5.66)%, t = 2.30, P = 0.025] were significantly higher in the observation group. Compared with before treatment, gait speed [(1.07 ± 0.27) m/s vs. (0.90 ± 0.30) m/s, t = 7.66, P < 0.001], grip strength [(20.62 ± 5.07) kg vs. (19.42 ± 5.78) kg, t = 3.55, P < 0.001], albumin [(231.38 ± 49.40) g/L vs. (200.26 ± 65.87) g/L, t = 3.70, P < 0.001] and prealbumin [(39.53 ± 3.45) g/L vs. (35.81 ± 4.46) g/L, t = 4.08, P < 0.001] levels in the observation group were significantly increased after treatment. There were no significant differences in gait speed, grip strength, albumin, and prealbumin levels in the control group before and after treatment (all P > 0.05). Conclusions:The method of strengthening the spleen to nourish the lung shows good clinical efficacy in treating stable COPD with lung and spleen deficiency complicated by sarcopenia, and it has great potential for broader application.

Objective To investigate the genetic risk factors of deep vein thrombosis(DVT)after trauma.Methods In a nested case-control study,50 patients with DVT after traumatic lower extremity fractures and 50 patients without DVT were recruited.The two groups were matched with gender,age and fracture sites.Preoperative venography was performed to diagnose DVT in trauma patients.Genome wide association study(GWAS)was used to investigate the genetic risk factors for preoperative DVT after traumatic lower ex-tremity fractures.Genomic DNA in leukocytes from blood sample was extracted and used for GWAS.Results GWAS was conducted based on 2 662 single nucleotide variants(SNV)which were dispersed in 144 interested genes.Ten genes were found to have signifi-cant association with trauma-related DVT,including cofactors of hemostasis mechanism,i.e.,THBD,F5,SERPIND1 and ITGA2,the factors related to vitamin K-dependent(VKD)carboxylation,i.e.,GGCX and CALU,and the members of cytochrome P450 family,i.e.,CYP1A1,CYP3A4,CYP2C19 and CYP2B6.Conclusion DVT after trauma might be regulated by the cofactors of hemostasis mechanism,the factors related to VKD carboxylation and the members of cytochrome P450 family.The results of our study may provide reference and inspiration for genetic susceptibility of preoperative DVT after trauma.

Objective:To investigate the clinical manifestations, endoscopic characteristics, and prognostic factors of patients with colorectal extranodal NK/T cell lymphoma.Methods:The clinical data of 52 patients with colorectal extranodal NK/T cell lymphoma admitted to the First Affiliated Hospital of Zhengzhou University from January 2013 to January 2023 were retrospectively analyzed. Their clinical manifestations and endoscopic characteristics were summarized, and the prognostic factors were analyzed by Cox regression model.Results:Among the 52 patients with colorectal extranodal NK/T cell lymphoma, there were 35 males and 17 females, with a male-to-female ratio of 2.06∶1. Among the general symptoms, abdominal pain was the most common (39 cases), and B symptoms occurred in 47 patients, among which fever was the most common lymphoma B symptom (42 cases), and gastrointestinal perforation was the most common complication (18 cases). Forty-three patients underwent colonoscopy, and the main manifestations under endoscopy were the ulceration type (24 cases). The ulcers were irregular at the edges and often covered with moss at the bottom. The median survival time was 4.3 months. Multivariate Cox regression analysis showed that hemocytic syndrome ( HR=8.50,95% CI: 1.679-8.328, P=0.001), serum albumin ( HR=3.59,95% CI: 1.017-6.551, P=0.048), and with or without chemotherapy ( HR=0.31, 95% CI: 0.246-1.061, P=0.025) were independent factors influencing the overall survival of patients with colorectal extranodal NK/T cell lymphoma. Conclusions:Colorectal extranodal NK/T cell lymphoma is a rare disease with a very poor prognosis. When patients present with abdominal pain and lymphoma B symptoms, and when ulcers with irregular edges and moss covering the bottom are found under endoscopy, the disease should be considered, and endoscopic biopsy should be taken in time for pathological diagnosis. The prognosis of patients with hemophagocytic syndrome and hypoproteinemia is poor. This disease should be treated with chemotherapy and surgery, and on this basis, hemophagocytic syndrome and hypoproteinemia should be treated to improve the prognosis of patients.

Objective:To prepare advanced platelet-rich fibrin (A-PRF)/chitosan thermosensitive hydrogel (hereinafter referred to as composite hydrogel) and explore the effects of composite hydrogel on full-thickness skin defect wound healing in diabetic rats.Methods:This study was an experimental study. The composite hydrogel with porous mesh structure and thermosensitive characteristics was successfully prepared, containing A-PRF with mass concentrations of 10, 15, 20, 50, and 100 g/L. Diabetic model was successfully established in male Sprague-Dawley rats aged 6-8 weeks by intraperitoneal injection of streptozotocin, and 4 full-thickness skin defect wounds were established on the back of each rat (finally the model was successfully established in 36 rats). Three wounds of each rat were divided into blank group (no drug intervention), positive control group (dropping recombinant human granulocyte-macrophage stimulating factor gel), and chitosan hydrogel group (dropping chitosan hydrogel solution). Thirty rats were collected, and the remaining one wound of each rat (totally 30 wounds) was divided into 10, 15, 20, 50, and 100 g/L composite hydrogel groups, with 6 wounds in each group, which were dropped with composite hydrogel solution containing 10, 15, 20, 50, and 100 g/L A-PRF, respectively. Taking the remaining six rats, the remaining one wound from each rat was dropped with composite hydrogel solution containing 100 g/L A-PRF. On 14 d after injury, 6 rats with one wound dropped with composite hydrogel containing 100 g/L A-PRF were selected for hematoxylin-eosin (HE) staining to observe the inflammation, hemorrhage, or necrosis of the heart, liver, spleen, lung, and kidney. On 10 d after injury, 6 rats with one wound dropped with composite hydrogel containing 15 g/L A-PRF were selected to observe the blood perfusion of wounds in the four groups (with sample size of 6). On 7 and 14 d after injury, the wound healing rates in the eight groups were calculated. On 14 d after injury, the wound tissue in the eight groups was taken for HE and Masson staining to observe the formation of new epithelium and collagen formation, respectively; the positive expressions of CD31 and vascular endothelial growth factor A (VEGFA) were detected by immunohistochemistry, and the percentages of positive areas were calculated; the protein expressions of CD31 and VEGFA were detected by Western blotting; the mRNA expressions of CD31 and VEGFA were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction method (with all sample sizes of 4).Results:On 14 d after injury, no obvious inflammation, hemorrhage, or necrosis was observed in the heart, liver, spleen, lung, and kidney in the 6 rats. On 10 d after injury, the blood perfusion volume of wound in 15 g/L composite hydrogel group was significantly more than that in blank group, positive control group, and chitosan hydrogel group, respectively (with P values all <0.05). On 7 and 14 d after injury, the wound healing rates of blank group were (26.0±8.9)% and (75.0±1.8)%, which were significantly lower than those of positive control group, chitosan hydrogel group, and 10, 15, 20, 50, and 100 g/L composite hydrogel groups, respectively ((45.8±3.2)%, (49.8±3.7)%, (51.2±2.9)%, (68.5±2.4)%, (68.8±1.5)%, (72.7±2.1)%, (75.0±3.7)% and (79.1±1.9)%, (77.2±1.7)%, (82.3±1.3)%, (89.6±1.9)%, (89.8±1.3)%, (87.3±1.1)%, (87.9±1.3)%), P<0.05; the wound healing rates of positive control group, chitosan hydrogel group, and 10 g/L composite hydrogel group were significantly lower than those of 15, 20, 50, and 100 g/L composite hydrogel groups ( P<0.05). On 14 d after injury, the wound epithelialization degrees of 15, 20, 50, and 100 g/L composite hydrogel groups were higher than those of the other 4 groups, the new microvascular situation was better, and the collagen was more abundant and arranged more neatly. On 14 d after injury, the percentages of CD31 and VEGFA positive areas in wounds in positive control group and the percentage of VEGFA positive area in wounds in chitosan hydrogel group were significantly higher than those in blank group ( P<0.05), the percentage of VEGFA positive area in wounds in 10 g/L composite hydrogel group was significantly higher than that in blank group, chitosan hydrogel group, and positive control group (with P values all <0.05), and the percentages of CD31 and VEGFA positive areas in wounds in 15, 20, 50, and 100 g/L composite hydrogel groups were significantly higher than those in blank group, positive control group, chitosan hydrogel group, and 10 g/L composite hydrogel group ( P<0.05). On 14 d after injury, the protein and mRNA expressions of CD31 and VEGFA in wound tissue in chitosan hydrogel group, positive control group, and 10 g/L composite hydrogel group were significantly higher than those in blank group ( P<0.05); the protein expression of VEGFA in wound tissue in 10 g/L composite hydrogel group was significantly higher than that in positive control group ( P<0.05), and the mRNA expressions of CD31 and VEGFA in wound tissue in 10 g/L composite hydrogel group were significantly higher than those in positive control group and chitosan hydrogel group ( P<0.05); the protein and mRNA expressions of CD31 and VEGFA in wound tissue in 15, 20, 50, and 100 g/L composite hydrogel groups were significantly higher than those in blank group, positive control group, chitosan hydrogel group, and 10 g/L composite hydrogel group ( P<0.05); the mRNA expressions of CD31 and VEGFA in wound tissue in chitosan hydrogel group were significantly lower than those in positive control group ( P<0.05). Conclusions:The composite hydrogel has high biological safety, can improve wound blood perfusion, effectively promote the formation of blood vessels and collagen in wound tissue, thus promoting the wound healing of full-thickness skin defects in diabetic rats. 15 g/L is the optimal mass concentration of A-PRF in composite hydrogel.