1.A Computational Perspective on Differences Between MHC-I and MHC-II in TCR-pMHC Structure Prediction Resources: Review and Benchmarking
Xiao-Qin WU ; Da-Wei LIU ; Bin-Yu LI ; Yang LIU ; Yang CAO ; Wen-Tao DAI
Progress in Biochemistry and Biophysics 2026;53(5):1376-1399
The initiation of adaptive immune responses relies on the precise recognition and interpretation of antigenic information. In this process, the specific binding of T cell receptors (TCRs) to peptide-major histocompatibility complex (pMHC) molecules represents one of the key molecular events in the initiation of adaptive immune responses. Accordingly, the structural features of TCR-pMHC complexes provide a fundamental basis for dissecting antigen recognition mechanisms and support rational vaccine design, therapeutic target discovery in TCR-based immunotherapy, and TCR identification and optimization. However, experimental determination of TCR-pMHC structures remains costly, time-consuming, and limited in coverage, making computational approaches essential for rapidly obtaining reliable structural information. Computational methods for predicting the structures of TCR-pMHC complexes have advanced rapidly in recent years, driven by progress in deep learning-based modeling frameworks and the increasing availability of structural and sequence resources. Despite these developments, most existing tools do not adequately distinguish the key structural and biophysical differences between MHC class I (MHC-I) and MHC class II (MHC-II) complexes during model construction. As a consequence, their predictive performance differs substantially between class I and class II complexes. In general, structural predictions for class I complexes outperform those for class II complexes. This discrepancy may be related to several fundamental differences between the two systems, including the architecture of the peptide-binding groove, the distribution of peptide lengths, and the properties of peptide flanking residues (PFRs). Compared with MHC-I molecules, MHC-II molecules usually bind longer antigenic peptides, which typically range from 13 to 25 amino acids in length. PFRs at both termini of these peptides participate in regulating the overall conformation of TCR-pMHC class II complexes and exert a pronounced effect on the geometric and physicochemical characteristics of the TCR-pMHC binding interface. Furthermore, within the TCR recognition interface, the complementarity-determining regions (CDRs) consist of segments that differ markedly in conformational behavior. They commonly include regions that are relatively rigid and structurally stable, together with highly flexible segments exhibiting substantial conformational plasticity. These rigidity-flexibility features constitute an essential structural basis enabling TCRs to recognize diverse peptide-MHC ligands and to accommodate conformational heterogeneity at the interface. However, many current modeling tools, in an effort to enforce global conformational stability or reduce structural noise, tend to over-constrain intrinsically flexible regions. Such oversimplification may lead to inappropriate rigidification of flexible CDR loops, resulting in local structural distortions, compromised interface geometry, or even complete modeling failure for specific complexes. Against this background, the review approaches the field from the perspective of computational differences between MHC-I and MHC-II complexes. We first systematically organize and summarize available resources related to TCRs and pMHCs, including structural datasets, sequence databases, prediction tools, and benchmarking studies. We then focus on five representative tools capable of predicting both class I and class II complexes—AlphaFold2, AlphaFold3, TCRmodel2, tFold-TCR, and TCR-pHLA_ModellerS. After excluding structures present in the training sets of these tools, we constructed a benchmark dataset comprising 25 class I and 10 class II TCR-pMHC complexes in the bound state and conducted a systematic evaluation using this dataset. We first employ widely used general evaluation metrics, including All-Atom Root Mean Square Deviation (All-Atom RMSD), Backbone RMSD, Template Modeling score (TM-score), and DockQ, to assess the global conformational accuracy and interface modeling quality of class I and class II complexes. For class II complexes, we propose for the first time a peptide flanking residue deviation index, including the PFRs-Deviation Index (PFRs-DI), N-PFR-Deviation Index (N-PFR-DI), and C-PFR-Deviation Index (C-PFR-DI), to quantitatively characterize conformational deviations in PFRs. In addition, we propose the CDR conformational consistency index (CCC) designed to qualitatively evaluate the ability of prediction tools to capture TCR CDR conformational flexibility. These metrics collectively assess a tool’s ability to model both overall conformation and critical functional regions, thereby addressing the limitations of existing evaluation criteria that overemphasize global structure while inadequately capturing modeling quality in key functional areas. This establishes a unified analytical framework for MHC-I and MHC-II complexes to guide data resource selection, modeling strategy formulation, and evaluation system development. The framework further advances computational modeling and provides crucial support for multi-scale analysis of TCR-pMHC recognition mechanisms and their biological functions.
2.A Computational Perspective on Differences Between MHC-I and MHC-II in TCR-pMHC Structure Prediction Resources: Review and Benchmarking
Xiao-Qin WU ; Da-Wei LIU ; Bin-Yu LI ; Yang LIU ; Yang CAO ; Wen-Tao DAI
Progress in Biochemistry and Biophysics 2026;53(5):1376-1399
The initiation of adaptive immune responses relies on the precise recognition and interpretation of antigenic information. In this process, the specific binding of T cell receptors (TCRs) to peptide-major histocompatibility complex (pMHC) molecules represents one of the key molecular events in the initiation of adaptive immune responses. Accordingly, the structural features of TCR-pMHC complexes provide a fundamental basis for dissecting antigen recognition mechanisms and support rational vaccine design, therapeutic target discovery in TCR-based immunotherapy, and TCR identification and optimization. However, experimental determination of TCR-pMHC structures remains costly, time-consuming, and limited in coverage, making computational approaches essential for rapidly obtaining reliable structural information. Computational methods for predicting the structures of TCR-pMHC complexes have advanced rapidly in recent years, driven by progress in deep learning-based modeling frameworks and the increasing availability of structural and sequence resources. Despite these developments, most existing tools do not adequately distinguish the key structural and biophysical differences between MHC class I (MHC-I) and MHC class II (MHC-II) complexes during model construction. As a consequence, their predictive performance differs substantially between class I and class II complexes. In general, structural predictions for class I complexes outperform those for class II complexes. This discrepancy may be related to several fundamental differences between the two systems, including the architecture of the peptide-binding groove, the distribution of peptide lengths, and the properties of peptide flanking residues (PFRs). Compared with MHC-I molecules, MHC-II molecules usually bind longer antigenic peptides, which typically range from 13 to 25 amino acids in length. PFRs at both termini of these peptides participate in regulating the overall conformation of TCR-pMHC class II complexes and exert a pronounced effect on the geometric and physicochemical characteristics of the TCR-pMHC binding interface. Furthermore, within the TCR recognition interface, the complementarity-determining regions (CDRs) consist of segments that differ markedly in conformational behavior. They commonly include regions that are relatively rigid and structurally stable, together with highly flexible segments exhibiting substantial conformational plasticity. These rigidity-flexibility features constitute an essential structural basis enabling TCRs to recognize diverse peptide-MHC ligands and to accommodate conformational heterogeneity at the interface. However, many current modeling tools, in an effort to enforce global conformational stability or reduce structural noise, tend to over-constrain intrinsically flexible regions. Such oversimplification may lead to inappropriate rigidification of flexible CDR loops, resulting in local structural distortions, compromised interface geometry, or even complete modeling failure for specific complexes. Against this background, the review approaches the field from the perspective of computational differences between MHC-I and MHC-II complexes. We first systematically organize and summarize available resources related to TCRs and pMHCs, including structural datasets, sequence databases, prediction tools, and benchmarking studies. We then focus on five representative tools capable of predicting both class I and class II complexes—AlphaFold2, AlphaFold3, TCRmodel2, tFold-TCR, and TCR-pHLA_ModellerS. After excluding structures present in the training sets of these tools, we constructed a benchmark dataset comprising 25 class I and 10 class II TCR-pMHC complexes in the bound state and conducted a systematic evaluation using this dataset. We first employ widely used general evaluation metrics, including All-Atom Root Mean Square Deviation (All-Atom RMSD), Backbone RMSD, Template Modeling score (TM-score), and DockQ, to assess the global conformational accuracy and interface modeling quality of class I and class II complexes. For class II complexes, we propose for the first time a peptide flanking residue deviation index, including the PFRs-Deviation Index (PFRs-DI), N-PFR-Deviation Index (N-PFR-DI), and C-PFR-Deviation Index (C-PFR-DI), to quantitatively characterize conformational deviations in PFRs. In addition, we propose the CDR conformational consistency index (CCC) designed to qualitatively evaluate the ability of prediction tools to capture TCR CDR conformational flexibility. These metrics collectively assess a tool’s ability to model both overall conformation and critical functional regions, thereby addressing the limitations of existing evaluation criteria that overemphasize global structure while inadequately capturing modeling quality in key functional areas. This establishes a unified analytical framework for MHC-I and MHC-II complexes to guide data resource selection, modeling strategy formulation, and evaluation system development. The framework further advances computational modeling and provides crucial support for multi-scale analysis of TCR-pMHC recognition mechanisms and their biological functions.
3.Transcatheter aortic valve replacement for aortic regurgitation complicated by Takayasu arteritis: A case report
Jianbin GAO ; Jian LI ; Yu YANG ; Mier MA ; Kairui YANG ; Wei LUO ; Ning WANG ; Da ZHU ; Wenbin OUYANG ; Xiangbin PAN
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2026;33(01):163-166
Patients with Takayasu arteritis combined with aortic valve disease often have a poor prognosis following surgical valve replacement, frequently encountering complications such as perivalvular leakage, valve detachment, and anastomotic aneurysm. This article presents a high-risk case wherein severe aortic valve insufficiency associated with Takayasu arteritis was successfully managed through transcatheter aortic valve implantation via the transapical approach. The patient had satisfactory valve function with no complications observed during the six-month postoperative follow-up. This case provides a minimally invasive and feasible alternative for the clinical management of such high-risk patients.
4.The first record of Anopheles messeae (Diptera: Culicidae) parasitized by water mites in China
Xue-ru CHEN ; Wen-zhen YAO ; Yu-hao LI ; Gui-chang LI ; Tao MENG ; Qun-ling FENG ; Xin-hui LIU ; Li-hong QIAO ; Xiang-ting WU ; Xue-feng ZHANG ; Cheng-lin LI ; Xue-cheng DONG ; Da-wei WANG ; Xiao-yan SI ; Yu-hong GUO
Acta Parasitologica et Medica Entomologica Sinica 2026;33(1):53-57
Objective This study reports on the obligatory parasitism of water mites Arrenurus sp. on Anopheles messeae at the Manzhouli Port, Inner Mongolia, China. Methods Duing July 2024, a survey on the mosquito diversity was conducted at the Manzhouli Port. Captured mosquitoes and their ectoparasites were identified to species level. Results A total of 1840 adult mosquitoes were collected, representing species from three genera: Culex(Cx. modestus, Cx. pipiens pallens), Aedes(Ae. dorsalis, Ae. flavidorsalis, Ae. flavescens), and Anopheles (An. messeae). Among all the mosqutioes specimens,3 out of 150 captured An. messeae were found to carry ectoparasitic mites, with number of 2,4,27 mites separately. Morphological and molecular identification reached the same result as water mites(Hydrachnidiae, Hydracrina). COI gene sequence showed 94% similarity with the closest species Arrenurus truncatellus. Conlusions Literature review suggests water mites are host-specific parasitism of mosquito species and herein with the first record of Arrenurus sp. parasiting on An. Messeae in the most high-latitude region globally.
5.Water extract of Rehmannia glutinosa improves bleomycin-induced pulmonary fibrosis in mice and its metabolic mechanism
Zi-yu ZHANG ; Meng-nan ZENG ; Peng-li GUO ; Yu-han ZHANG ; Xiang-da LI ; Yan-xing WU ; Shuang-ying FU ; Zi-chang LIAN ; Wei-sheng FENG ; Xiao-ke ZHENG
Chinese Pharmacological Bulletin 2025;41(12):2315-2325
Aim To investigate the intervention effect of Rehmannia radix water extract on bleomycin(BLM)-induced pulmonary fibrosis in mice combined with metabolomics and to reveal the potential mechanism,in order to provide new ideas for clinical treatment of pul-monary fibrosis.Methods Male C57BL/6N mice were randomly divided into the control group,model group,pirfenidone group(positive control,PFD,270 mg·kg-1),and low dose(DH-L,4.55 g·kg-1)group,medium dose(DH-M,9.1 g·kg-1)group and high dose(DH-H,18.2 g·kg-1)group of Rehman-nia.Except for the control group,BLM(5 mg·kg-1)was instilled into the trachea to establish the model of pulmonary fibrosis in the other groups.The survival rate,lung index and blood oxygen saturation of mice in each group were evaluated.HE and Masson staining were used to observe the pathological changes of lung tissue.WBP was used to detect lung function.Flow cytometry was used to detect the apoptosis of primary lung cells,ROS and immune cells.ELISA was used to detect the levels of fibrosis markers and inflammatory factors(α-SMA,collagen Ⅰ,collagen Ⅲ,TGF-β1,TNF-α,IL-1 β,and IL-6).Biochemical method was employed to detect the contents of GSH-Px,T-SOD and MDA.Liquid chromatograph mass spectrometer(LC-MS)metabolomics was used to analyze the changes of serum metabolic profile.Results Water extract of Re-hmannia significantly increased the survival rate,oxy-gen saturation and lung function of mice with pulmona-ry fibrosis,reduced the lung coefficient,ameliorated pathological damage and collagen deposition in lung tissue,reduced the levels of apoptosis and oxidative stress,and down-regulated the levels of inflammatory factors in lung tissue.It regulated the levels of metabo-lites such as bile acid metabolism,sphingolipid metabo-lism,and unsaturated fatty acid metabolism.Conclu-sions Water extract of Rehmannia inhibits lung injury and collagen deposition in mice with pulmonary fibrosis by inhibiting inflammatory response,which may be a-chieved by regulating the levels of inflammatory factors through the metabolic pathways of bile acid and sphin-golipid.
6.CiteSpace-based literature visualization analysis of brain-computer interface technology applied in rehabilitation of stroke patients
Yu-wei HAN ; Da HUO ; Li-gang CHEN ; Xin-yu YANG ; Hai JIN ; Xiao-ming LI ; Guo-biao LIANG ; Chun-yong YU
Chinese Medical Equipment Journal 2025;46(9):65-69
Relevant China's literature on the application of brain-computer interface technology in the field of rehabilita-tion of stroke patients was retrieved in the China Knowledge Network database from its establishment to December 31,2024,and CiteSpace visual analysis software was used to analyze the selected literature in terms of trend of annual publica-tion number,author collaboration network,keyword co-occurrences and emergences and to generate a corresponding knowledge map.It's pointed out brain-computer interface technology showed significant application potential for motor function recovery and neurorehabilitation,which had the research hotspots of the cross technologies covering motor imagina-tion,rehabilitation training and virtual reality and the research frontiers of the fusion application of intelligent algorithms of deep learning and pattern recognition.The challenges and future development directions of the field were investigated,and references were provided for promoting the application of brain-computer interface technology to rehabilitation of sroke patients in China.[Chinese Medical Equipment Journal,2025,46(9):65-69]
7.CiteSpace-based literature visualization analysis of brain-computer interface technology applied in rehabilitation of stroke patients
Yu-wei HAN ; Da HUO ; Li-gang CHEN ; Xin-yu YANG ; Hai JIN ; Xiao-ming LI ; Guo-biao LIANG ; Chun-yong YU
Chinese Medical Equipment Journal 2025;46(9):65-69
Relevant China's literature on the application of brain-computer interface technology in the field of rehabilita-tion of stroke patients was retrieved in the China Knowledge Network database from its establishment to December 31,2024,and CiteSpace visual analysis software was used to analyze the selected literature in terms of trend of annual publica-tion number,author collaboration network,keyword co-occurrences and emergences and to generate a corresponding knowledge map.It's pointed out brain-computer interface technology showed significant application potential for motor function recovery and neurorehabilitation,which had the research hotspots of the cross technologies covering motor imagina-tion,rehabilitation training and virtual reality and the research frontiers of the fusion application of intelligent algorithms of deep learning and pattern recognition.The challenges and future development directions of the field were investigated,and references were provided for promoting the application of brain-computer interface technology to rehabilitation of sroke patients in China.[Chinese Medical Equipment Journal,2025,46(9):65-69]
8.Comparative effectiveness of small optical zone orthokeratology lenses and repeated low-level red-light therapy for controlling myopia in adolescents
Shi-mei LIU ; Li CHEN ; Da LUO ; Qi-hui LUO ; Yu CHENG ; Ren-xiang TANG ; Wei YANG ; Bo LIU
Journal of Regional Anatomy and Operative Surgery 2025;34(11):972-976
Objective To compare the effect of small optical zone orthokeratology lenses(OK lenses)and repeated low-level red-light(RLRL)therapy in controlling myopia progression for adolescents,and the therapeutic effectiveness of RLRL is evaluated.Methods A retrospective analysis was conducted on the clinical data of 80 adolescent myopic patients in the First Affiliated Hospital of Army Medical University.The patients were divided into the RLRL group and the OK lenses group according to different intervention methods,with 40 cases in each group.Patients in the RLRL group received RLRL therapy combined with single-vision spectacles,and patients in the OK lenses group were treated with OK lenses.The changes of spherical equivalent(SE),axial length and subfoveal choroidal thickness(SFCT)1,3,6,and 12 months after treatment compared with the baseline,and color vision of patients were assessed.Based on the mean baseline axial length of the RLRL group,the patients in this group were subdivided into the short axial group and the long axial group,and the changes of the axial length and SFCT were further analyzed.Results The diopter 1,3,6,and 12 months after treatment in the RLRL group were not significantly different from the baseline(P>0.05).Axial lengths of patients in the RLRL group progressively shortened after treatment and returned close to the baseline 12 months after treatment.In contrast,axial lengths of patients in the OK lens continued to grow within 12 months after treatment;the axial lengths at each time point after treatment of patients in the two groups were significantly different from the baseline(P<0.05).The changes of axial length of patients in the RLRL group at each time point after treatment were significantly smaller than those in the OK lenses group(P<0.05).The SFCT changes of patients in the RLRL group at each time point after treatment were all greater than those in the OK lenses group(P<0.05).The SFCT at each time point after treatment in the RLRL group were significantly different from the baseline(P<0.05),whereas the SFCT at each time point after treatment in the OK lenses group were not significantly different from the baseline(P>0.05).The changes of axial length at each time point after treatment of patients in the long axial group were all greater than those in the short axial group(P<0.05);the SFCT changes 6 months after treatment of patients in the long axial group was greater than that in the short axial group(P<0.05);the SFCT at each time point after treatment of patients in the two groups were signifi-cantly different from the baseline(P<0.05).Color vision tests revealed no abnormities after treatment in the RLRL group and the OK lenses group.Conclusion RLRL therapy is effective in controlling myopia progression and demonstrates superior axial length control compared to orthokeratology lenses.
9.Comparative effectiveness of small optical zone orthokeratology lenses and repeated low-level red-light therapy for controlling myopia in adolescents
Shi-mei LIU ; Li CHEN ; Da LUO ; Qi-hui LUO ; Yu CHENG ; Ren-xiang TANG ; Wei YANG ; Bo LIU
Journal of Regional Anatomy and Operative Surgery 2025;34(11):972-976
Objective To compare the effect of small optical zone orthokeratology lenses(OK lenses)and repeated low-level red-light(RLRL)therapy in controlling myopia progression for adolescents,and the therapeutic effectiveness of RLRL is evaluated.Methods A retrospective analysis was conducted on the clinical data of 80 adolescent myopic patients in the First Affiliated Hospital of Army Medical University.The patients were divided into the RLRL group and the OK lenses group according to different intervention methods,with 40 cases in each group.Patients in the RLRL group received RLRL therapy combined with single-vision spectacles,and patients in the OK lenses group were treated with OK lenses.The changes of spherical equivalent(SE),axial length and subfoveal choroidal thickness(SFCT)1,3,6,and 12 months after treatment compared with the baseline,and color vision of patients were assessed.Based on the mean baseline axial length of the RLRL group,the patients in this group were subdivided into the short axial group and the long axial group,and the changes of the axial length and SFCT were further analyzed.Results The diopter 1,3,6,and 12 months after treatment in the RLRL group were not significantly different from the baseline(P>0.05).Axial lengths of patients in the RLRL group progressively shortened after treatment and returned close to the baseline 12 months after treatment.In contrast,axial lengths of patients in the OK lens continued to grow within 12 months after treatment;the axial lengths at each time point after treatment of patients in the two groups were significantly different from the baseline(P<0.05).The changes of axial length of patients in the RLRL group at each time point after treatment were significantly smaller than those in the OK lenses group(P<0.05).The SFCT changes of patients in the RLRL group at each time point after treatment were all greater than those in the OK lenses group(P<0.05).The SFCT at each time point after treatment in the RLRL group were significantly different from the baseline(P<0.05),whereas the SFCT at each time point after treatment in the OK lenses group were not significantly different from the baseline(P>0.05).The changes of axial length at each time point after treatment of patients in the long axial group were all greater than those in the short axial group(P<0.05);the SFCT changes 6 months after treatment of patients in the long axial group was greater than that in the short axial group(P<0.05);the SFCT at each time point after treatment of patients in the two groups were signifi-cantly different from the baseline(P<0.05).Color vision tests revealed no abnormities after treatment in the RLRL group and the OK lenses group.Conclusion RLRL therapy is effective in controlling myopia progression and demonstrates superior axial length control compared to orthokeratology lenses.
10.Observation on therapeutic effect of self-made auxiliary reduction device combined with sinus tarsi approach in treatment of Sanders type Ⅱ to Ⅳ calcaneal fractures
Yu ZHOU ; Da-gang TANG ; Wei PENG ; Xiao-bo HU ; Zhi CHEN ; Peng LONG ; Zhi-ping KUANG ; Chuan-zhi ZHANG
Journal of Regional Anatomy and Operative Surgery 2025;34(7):604-609
Objective To observe the efficacy of self-made auxiliary reduction device combined with sinus tarsi approach(STA)in the treatment of Sanders type Ⅱ to Ⅳ calcaneal fractures.Methods A total of 40 patients with Sanders type Ⅱ to Ⅳ calcaneal fractures admitted to our hospital from January to June 2023 were selected and divided into the control group and the observation group by the random number table method,with 20 cases in each group.Patients in the control group underwent surgical treatment with the heel extensile lateral approach(ELA),while patients in the observation group underwent surgical treatment with the auxiliary reduction device combined with STA.The surgical-related indicators,postoperative complications and ankle-foot anatomical indicators of patients in the two groups were compared.The recovery of limb function was evaluated by the American Orthopaedic Foot and Ankle Society(AOFAS)ankle-hindfoot scale and Maryland foot function score.Results There was no statistically significant difference in the operation time,postoperative incision drying time,or duration of postoperative pain between the two groups(P>0.05).The postoperative suture removal time of the patients in the observation group was shorter than that of the control group,and the difference was statistically significant(P<0.05).The incidence of skin edge necrosis of incision and the total incidence of complications of patients in the observation group were significantly lower than those in the control group(P<0.05).The B?hler angle and Gissane angle of patients in both groups increased after surgery compared with those before surgery(P<0.05);there was no statistically significant difference in the B?hler angle or Gissane angle after surgery of patients between the two groups(P>0.05).The AOFAS score1 week after surgery of the patients in the observation group was higher than that in the control group(P<0.05),while there were no statistically significant differences in the AOFAS scores or Maryland scores of patients at other time points between the two groups(P>0.05).Conclusion The use of the auxiliary reduction device in surgical treatment with STA for Sanders type Ⅱ to Ⅳ calcaneal fractures can effectively restore the function of the foot and ankle,with short postoperative suture removal time and low incidence of postoperative complications.


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