As a pivotal strategy to alleviate the shortage of organ donors, xenotransplantation has achieved remarkable advances in both pre-clinical and clinical studies in recent years, driven by continuous optimization of gene modification techniques and immunosuppressive regimens. Nevertheless, clinical translation still confronts formidable challenges, including rejection and heightened infection risks, which severely compromise long-term graft survival. Consequently, the role of immunosuppressive regimens in xenotransplantation has become increasingly prominent. This article summarizes the mechanisms underlying xenogeneic immune rejection, the latest developments in immunosuppressive regimens, cutting-edge strategies for inducing immune tolerance and the major hurdles facing clinical xenotransplantation. It delves into potential optimization strategies and directions for future clinical research, aiming to offer theoretical insights and practical guidance for the safe and effective application of clinical xenotransplantation.

BACKGROUND:At present,there are few reports on the postoperative efficacy of arthroscopic coracoid tunnel-free suspension fixation and coracoid single tunnel fixation in the treatment of acromioclavicular joint dislocation at home and abroad.The specific clinical efficacy of the two procedures and whether there are other risks need to be explored. OBJECTIVE:To compare the short-term postoperative clinical efficacy of arthroscopic TightRope band plate fixation with single tunnel fixation of the coracoid process and tunnel-free suspension fixation of the coracoid process in the treatment of acute type Ⅲ-Ⅴ acromioclavicular joint dislocation. METHODS:A retrospective analysis was performed in 45 patients with acromioclavicular joint dislocation who met the inclusion criteria admitted to the Sixth Affiliated Hospital of Xinjiang Medical University from June 2019 to September 2022,and were divided into coracoid single tunnel fixation group(20 cases)and coracoid tunnel-free suspension fixation group(25 cases)according to the surgical treatment plan.Operation time,incision length,blood loss,Constant-Murley score,visual analogue scale score,the American Shoulder and Elbow Surgeons(ASES)score and intraoperative and postoperative complications of the shoulder joint before operation,3 months after surgery and the last follow-up were compared between the two groups. RESULTS AND CONCLUSION:All patients successfully completed the operation,and there was no important nerve or blood vessel damage during the operation.The operation time of the coracoid tunnel-free suspension fixation group was significantly shorter than that of the coracoid tunnel-free suspension fixation group(P<0.05).There was no significant difference in intraoperative blood loss and incision length between the two groups(P>0.05).All patients were followed up for 12 to 24 months,with an average of(15.29±2.73)months.In the coracoid single tunnel fixation group,at 3 months after operation and the final follow-up,the visual analogue scale score was significantly lower than the preoperative score(P<0.05);Constant-Murley score and ASES score were significantly increased compared with the preoperative values(P<0.05).In the coracoid tunnel-free suspension fixation group,at 3 months after operation and the final follow-up,the visual analogue scale score was significantly lower than the preoperative score(P<0.05);the Constant-Murley score and the ASES score were both significantly higher than the preoperative scores(P<0.05).At 3 months after operation,the Constant-Murley score of the coracoid tunnel-free suspension fixation group was higher than that of the coracoid single tunnel fixation group(P<0.05),while there was no significant difference in visual analogue scale and ASES scores between the two groups(P>0.05).There was also no significant difference in the visual analogue scale,Constant-Murley,and ASES scores between the two groups at the corresponding time points before surgery and at the final follow-up(P>0.05).Intraoperative and postoperative complications:In the coracoid single tunnel fixation group,there was one case of coracoid cortical rupture and fracture during the tunnel drilling during the operation,and one case of a loss of reduction at 3 months after operation,which was repositioned and fixed with hook plate transposition of the coracoacromial ligament.All patients had good acromioclavicular joint function recovery and no re-dislocation at the final follow-up.All patients in the coracoid tunnel-free suspension fixation group did not suffer from coracoid fractures,loss of reduction and other complications during surgery,postoperatively and at the last follow-up.To conclude,these two arthroscopic treatments for acute type Ⅲ-Ⅴ acromioclavicular joint dislocation have the advantages of less trauma,reliable reduction and fixation,and good recovery of shoulder joint function after operation.However,compared with the coracoid single tunnel technique,the coracoid tunnel-free suspension fixation requires shorter time,faster recovery of shoulder joint function in the short term,and avoids the establishment of bone tunnels on the coracoid process,which reduces the probability of iatrogenic fracture of the coracoid process during operation and provides a higher degree of safety.

Objective To introduce the modeling method of pendulum-like modified rat abdominal heart heterotopic transplantation model and evaluate the quality of the model. Methods An operator without transplantation experience performed 15 consecutive models, recorded the time of each step, changes in body weight and modified Stanford scores, and calculated the surgical success rate, postoperative 1-week survival rate and technical success rate. Ultrasound examinations was performed in 1 week postoperatively. Results The times for donor heart acquisition, donor heart processing, recipient preparation and transplantation anastomosis were (14.3±1.4) min, (3.5±0.6) min, (13.6±2.1) min and (38.3±5.2) min respectively. The surgical success rate was 87% (13/15), and the survival rate 1 week after operative was 100% (13/13). The improved Stanford score indicated a technical success rate of 92% (12/13), and the postoperative 1-week ultrasound examination showed that grafts with Stanford scores ≥3 had detectable pulsation and blood flow signals. Conclusions The pendulum-like modified rat abdominal heart heterotopic transplantation improved model further optimizes the operational steps with a high success rate and stable quality, may be chosen as a modeling option for basic research in heart transplantation in the future.

Xenotransplantation is one of the effective ways to overcome the shortage of donor organs. However, the molecular incompatibility between xenotransplantation donors and recipients can cause rejection, which greatly limits the clinical application of xenotransplantation. In recent years, researchers have deeply explored the mechanism of xenotransplantation rejection through xenotransplantation models of pig-to-monkey and pig-to-brain death recipients, and found that the innate immune system plays an important role in rejection. Macrophages, as phagocytes in the innate immune system, not only damage xenografts through phagocytosis but also interact with other immune cells to influence the immune microenvironment of xenotransplantation. However, due to the heterogeneity of macrophages, their phenotypes and functions in xenotransplantation rejection remain unclear. Therefore, it is necessary to further explore the role of macrophages in xenotransplantation rejection. This article reviews the latest research progress of macrophages in xenotransplantation rejection, aiming to explore the mechanisms of macrophages in xenotransplantation rejection and provide references for future research.

Hypercoagulable state (HCS) after kidney transplantation is one of the common and serious complications in kidney transplant recipients, which has attracted increasing attention in recent years. HCS refers to the abnormal and excessive activation of blood coagulation function, leading to the increased risk of thrombosis. After kidney transplantation, the combined effects of hemodynamic changes, surgical trauma and severe rejection increase the incidence of HCS, not only raising the risk of thrombosis but also potentially causing graft failure and affecting the postoperative survival rate of patients. This article reviews the influencing factors, clinical manifestations, diagnostic methods and preventive strategies of HCS after kidney transplantation, aiming to provide a theoretical basis for optimizing perioperative management and improving the prognosis of patients.

Organ transplantation faces the challenge of a shortage of donors. Although xenotransplantation holds great potential, it is limited by rejection. Extracellular histones, as key members of damage-associated molecular patterns, have been proven in recent years to play a crucial role in transplant rejection by activating innate immunity, regulating the coagulation-inflammation network, and modulating adaptive immune responses. However, the specific functions and key mechanisms remain to be clarified. Therefore, this article reviews the structural characteristics of histones, their release pathways, the biological functions of extracellular histones, and their potential roles in xenotransplantation. It summarizes the latest research progress of extracellular histones in xenotransplantation, analyzes the shortcomings of existing research and the direction for future research, with the expectation of providing references for the application of extracellular histones in xenogeneic kidney transplantation.

Pulmonary fibrosis(PF)is a chronic progressive end-stage lung disease.However,the mechanisms un-derlying the progression of this disease remain elusive.Presently,clinically employed drugs are scarce for the treatment of PF.Hence,there is an urgent need for developing novel drugs to address such diseases.Our study found for the first time that a natural source of Prismatomeris connata Y.Z.Ruan(Huang Gen,HG)ethyl acetate extract(HG-2)had a significant anti-PF effect by inhibiting the expression of the transforming growth factor beta 1/suppressor of mothers against decapentaplegic(TGF-β1/Smad)pathway.Network pharmacological analysis suggested that HG-2 had effects on tyrosine kinase phosphorylation,cellular response to reactive oxygen species,and extracellular matrix(ECM)disassembly.Moreover,mass spec-trometry imaging(MSI)was used to visualize the heterogeneous distribution of endogenous metabolites in lung tissue and reveal the anti-PF metabolic mechanism of HG-2,which was related to arginine biosyn-thesis and alanine,asparate and glutamate metabolism,the downregulation of arachidonic acid meta-bolism,and the upregulation of glycerophospholipid metabolism.In conclusion,we elaborated on the relationship between metabolite distribution and the progression of PF,constructed the regulatory metabolic network of HG-2,and discovered the multi-target therapeutic effect of HG-2,which might be conducive to the development of new drugs for PF.

Pyroptosis is a kind of inflammatory cell death mediated by the Gasdermin family,which has made great progress in tumor therapy in recent years.Basing on that cell pyroptosis can activate the anti-tumor immune response,and tumor immunotherapy is a new field of tumor therapy,the regulation of cell pyroptosis exhibits great potential for tumor therapy.Meanwhile,nanotechnology is the key means of tumor precision treatment with the advantages of precise targeting and continuous release.Based on these current situations,this paper summarizes the drugs that activate pyroptosis and the nanocarriers that use nanotechnology to promote pyroptosis to participate in tumor therapy,and summarizes the mechanism and application of their action on pyroptosis.This paper is aimed to provide certain references for anti-tumor therapy based on pyroptosis.

Objective To investigate the dynamics of NK cells and Treg cells,as well as their potential prognostic significance in relation to TKI discontinuation among patients diagnosed with chronic myeloid leukemia(CML).Methods In this study,a total of 200 patients diagnosed with CML were randomly selected and divided into two groups:the discontinuation group(n=100)and the non-discontinuation group(n=100).Within the discontinuation group,patients were further categorized into a recurrence subgroup(n=41)and a non-recurrence subgroup(n=59).Clinical data and follow-up information of these patients were retrospectively analyzed.Logistic regression analysis was performed to investigate the impact of various variables on patient outcomes following drug discontinuation,as well as to explore independent factors influencing recurrence in these individuals.Receiver operating characteristic(ROC)curve analysis was employed to assess the predictive value of NK cells and Treg cells for TKI discontinuation outcomes.A significance level of P<0.05 was considered statistically significant.Results The proportion of patients treated with interferon in the discontinuation group was significantly higher than that in the non-discontinuation group(P<0.05).Moreover,the former group exhibited a significantly higher number of NK cells(P<0.05)and Treg cells(P<0.01)compared to the latter group.Compared to the recurrence group,there was a significant increase in the proportion of patients using interferon in the non-recurrence group(P<0.05),along with longer durations of TKI treatment and deep molecular response(DMR)duration(P<0.05).The number of NK cells and Treg cells in the non-recurrence group was significantly higher than that in the recurrence group(P<0.01).Logistic regression analysis found that the use of interferon(OR=1.25,95%CI:1.11～2.03,P<0.001),duration of DMR(OR=1.16,95%CI:1.08～1.92,P<0.05),NK cells(OR=1.64,95%CI:1.14～2.28,P<0.01),and Treg cells(OR=1.83,95%CI:1.15～2.42,P<0.01)were all influencing factors for the recurrence of patients after drug discontinuation.The results of ROC curve analysis showed that the AUC of NK cells combined with Treg cells for predicting the recurrence of TKI after discontinuation was 0.892(95%CI:0.857～0.927,P<0.001).Conclusion The frequencies of NK cells and Treg cells were significantly elevated in patients who remained recurrence-free following TKI discontinuation,highlighting the potential predictive value of combined NK cell and Treg cell analysis for drug cessation in CML patients.

Objective To explore the expression of serine proteinase inhibitor family E member 1(SERPINE1)in colon cancer and its effect on the malignant biological behaviors of colon cancer cells.Methods starBase and TISIDB databases were used to analyze the expression of SERPINE1 in 471 patients with colon cancer and 41 paracancerous tissues,and the relationships of its differential expression with clinical stage and prognostic survival were analyzed.The cancer specimens and paracancerous tissues from 5 patients with colon cancer were collected in No.940 Hospital of Joint Logistic Support Force,and RT-qPCR and Western blotting were employed to detect the expression of SERPINE1 at mRNA and protein levels.After lentiviral vectors of SERPINE1 overexpression and interference were constructed and transfected into colon cancer RKO and LoVo cells.The experimental cells were assessed by RT-qPCR and Western blotting to verify the efficiency of overexpression and interference.Then cell proliferation,migration,invasion and apoptosis were evaluated by CCK-8 assay,clone formation test,Transwell test and Hoechst apoptotic nuclear staining,respectviely.Finally,Western blotting was applied to determine the effect of SERPINE1 on phosphatidyl-inositol 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway.Results Database analysis showed that SERPINE1 was highly expressed,positively correlated with the clinical stage and negatively correlated with the overall survival in colon cancer patients(P＜0.05).Transfection of overexpression lentiviral vector resulted in enhanced cell proliferation,invasion and migration abilities while weakened apoptosis in RKO and LoVo cells.On the contrary,SERPINE1 interference reduced the abilities of cell proliferation,invasion and migration but improved cell apoptosis(P＜0.05).Western blotting showed that overexpression of SERPINE1 had no effect on the expression of PI3K and AKT,but increased the expression of p-PI3K and p-AKT,and SERPINE1 interference also had no change in PI3K and AKT expression and reduced the levels of their phosphorylation levels.Statistical differences were observed in relative quantitative analysis on the ratios of p-PI3K/PI3K and p-AKT/AKT(P＜0.05).Conclusion SERPINE1 is highly expressed,and correlated with clinical stage and prognosis of patients with colon cancer.Its overexpression promotes the proliferation,migration,invasion and inhibits apoptosis of colon cancer RKO and LoVo cells through PI3K/AKT signaling pathway.