[Objective] To study the molecular biological mechanism for a case of ABO blood group B subtype, and perform three-dimensional modeling of the mutant enzyme. [Methods] The ABO phenotype was identified by the tube method and microcolumn gel method; the ABO gene of the proband was detected by sequence-specific primer polymerase chain reaction (PCR-SSP), and the exon 6 and 7 of the ABO gene were sequenced and analyzed. Homologous modeling of Bw.03 glycosyltransferase (GT) was carried out by Modeller and analyzed by PyMOL2.5.0 software. [Results] The weakening B antigen was detected in the proband sample by forward typing, and anti-B antibody was detected by reverse typing. PCR-SSP detection showed B, O gene, and the sequencing results showed c.721 C>T mutation in exon 7 of the B gene, resulting in p. Arg 241 Trp. Compared with the wild type, the structure of Bw.03GT was partially changed, and the intermolecular force analysis showed that the original three hydrogen bonds at 241 position disappeared. [Conclusion] Blood group molecular biology examination is helpful for the accurate identification of ambiguous blood group. Homologous modeling more intuitively shows the key site for the weakening of Bw.03 GT activity. The intermolecular force analysis can explain the root cause of enzyme activity weakening.

ObjectiveTo investigate the potential mechanisms and pathways through which Gandouling （GDL） exerts its effects in the treatment of liver fibrosis in Wilson disease. MethodsSixty male SD rats were randomly divided into six groups： the normal group， the model group， the GDL low-， medium-， and high-dose groups （0.24， 0.48， 0.96 g·kg^-1）， and the penicillamine group （90 mg·kg^-1）， with 10 rats in each group. A copper-loaded Wilson disease rat model was established by gavage administration of 300 mg·kg^-1 copper sulfate pentahydrate to all groups except the normal group. Hematoxylin-eosin （HE） staining and Masson staining were used to observe the pathomorphological changes in the liver. Enzyme-linked immunosorbent assay （ELISA） was employed to measure the levels of hyaluronic acid （HA）， laminin （LN）， procollagen type-Ⅲ peptide （PC-Ⅲ）， and collagen type-Ⅳ （C-Ⅳ）. Transmission electron microscopy was used to examine the ultrastructure of liver tissues. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect the expression levels of liver tissues and serum exosomal long noncoding RNA H19 （LncRNA H19）， phosphatidylinositol 3-kinase （PI3K）， protein kinase B （Akt）， and mammalian target of rapamycin （mTOR）. Western blot analysis was performed to assess the expression levels of PI3K， Akt， mTOR， and their phosphorylated forms， as well as autophagy-related proteins Beclin1 and microtubule-associated protein 1 light chain 3B （LC3-Ⅱ/LC3-Ⅰ） in liver tissues. Beclin1 and LC3-Ⅱ fluorescence signal intensity was observed by immunofluorescence. ResultsCompared with the normal group， the model group exhibited inflammatory cell infiltration in hepatocytes， unclear nuclear boundaries with cell cleavage and necrosis， and collagen fiber deposition around confluent areas. The levels of HA， LN， PC-Ⅲ， and C-Ⅳ were significantly elevated （P<0.01）. Transmission electron microscopy revealed an increased number of autophagic vesicles， with autophagic lysosomes exhibiting a single-layer membrane structure following degradation of most envelopes. Expression levels of Beclin1 and LC3-Ⅱ/LC3-Ⅰ were significantly increased （P<0.01）， and fluorescence signals of Beclin1 and LC3-Ⅱ were markedly enhanced. The protein expression levels of PI3K， Akt， mTOR， p-PI3K， p-Akt， and p-mTOR were reduced （P<0.01）， while LncRNA H19 expression was increased （P<0.01）， and mRNA expression levels of PI3K， Akt， and mTOR were decreased （P<0.01）. After treatment with GDL， the degree of liver fibrosis was significantly improved， with decreased levels of HA， LN， PC-Ⅲ， and C-Ⅳ. The number of autophagic vesicles was significantly reduced， and expression levels of Beclin1 and LC3-Ⅱ/LC3-Ⅰ proteins were lower （P<0.01）. The fluorescence signals of Beclin1 and LC3-Ⅱ weakened dose-dependently. The protein levels of PI3K， Akt， mTOR， p-PI3K， p-Akt， and p-mTOR were elevated （P<0.01）， while the expression level of LncRNA H19 was reduced （P<0.01）. Furthermore， the mRNA expression levels of PI3K， Akt， and mTOR increased （P<0.05， P<0.01）. ConclusionGDL may alleviate liver fibrosis and reduce liver injury by regulating the PI3K/Akt/mTOR autophagy signaling pathway via LncRNA H19.

ObjectiveTo systematically review the available studies about Guanxinjing capsules in treating angina pectoris of coronary heart disease （syndrome of Qi deficiency and blood stasis）， evaluate the evidence quality and comprehensive value of Guanxinjing capsules in 6+1 dimensions involving 9 aspects， and clarify the clinical positioning and advantages of this medicine. MethodsA qualitative combined with quantitative evaluation method was adopted， involving clinical medicine， epidemiology， evidence-based medicine， and pharmacoeconomics. Through public data collection， questionnaire surveys， real-world data collection， and literature comprehensive evaluation， an evaluation system involving 9 aspects in 6+1 dimensions was constructed for Guanxinjing capsules. Experts assigned weights to the criterion layer and indicator layer， and the multi-criteria decision analysis （MCDA） model and CSC （V2.0） were employed to measure each dimension and reveal the clinical value of Guanxinjing capsules. Results①The evaluation results showed that Guanxinjing capsules are safe. According to the adverse reactions in the instructions， the systematic evaluation and meta-analysis of clinical safety， and the data collected by the National Center for Adverse Drug Reaction Monitoring， the adverse reactions of Guanxinjing capsules mainly include chest tightness， dyspnea， dizziness， and digestive system-related symptoms， with a standardized score of 0.75 points， which suggests good safety. ②The meta-analysis results suggest that according to the same efficacy standards， the effectiveness of Guanxinjing capsules alone and Guanxinjing capsules combined with conventional Western medicine or Chinese patent medicines is higher than that of conventional Western medicine or the Chinese patent medicine Shenshao capsules alone in treating coronary heart disease. The standardized score of effectiveness is 0.57， which indicates that the effectiveness still requires evidence support. ③With the individual disposable income in 2020 as the expected payment assumption threshold， compared with conventional treatment alone， combining Guanxinjing capsules with conventional treatment is cost-effective and economical for the patients with angina pectoris of coronary heart disease under certain conditions （higher than 106.91 yuan）， which suggests good economy. ④At present， 3 patents for the invention of Guanxinjing capsules have been approved， covering multiple fields such as clinical innovation， service system innovation， and industrial development， which implies good innovation. ⑤In addition， the questionnaire surveys for medical staff involve five different dimensions， and the statistical scores and evaluation results show good suitability of Guanxinjing capsules. ⑥The reimbursement rate of Guanxinjing capsules by residents is high. The sampling survey results show that Guanxinjing capsules are fully equipped in hospitals across China and have good accessibility. ⑦Derived from the theory of activating blood and resolving stasis proposed by Wang Qingren， a famous physician in the Qing Dynasty， Guanxinjing capsules integrate multiple therapies such as replenishing Qi， nourishing Yin， and aromatic warming and unblocking. According to the analysis data in the "6+1" dimensions， the clinical comprehensive evaluation score of Guanxinjing capsules for angina pectoris of coronary heart disease （syndrome of Qi deficiency and blood stasis） was 0.73. ConclusionThe results of comprehensive evaluation of each dimension and clinical value suggest that Guanxinjing capsules in treating angina pectoris of coronary heart disease （syndrome of Qi deficiency and blood stasis） have sufficient clinical evidence， good safety， suitability， and accessibility. It is recommended that Guanxinjing capsules can be included in the documents of basic clinical medication management in accordance with the established procedure.

Viral pneumonia is an infectious disease caused by virus invading the lung parenchyma and interstitial tissue and causing lung inflammation， with the incidence rising year by year. Traditional Chinese medicine （TCM） can treat viral pneumonia in a multi-component， multi-target， and holistic manner by targeting the core pathogenesis of pneumonia caused by different respiratory viruses， demonstrating minimal side effects and significant advantages. According to the theory of healthy Qi and pathogenic Qi in TCM， the struggle between healthy Qi and pathogenic Qi and the imbalance between immunity and inflammation run through the entire process of viral pneumonia， and the immunity-inflammation status at different stages of the disease reflects different relationships between healthy Qi and pathogenic Qi. Immune dysfunction leads to the deficiency of healthy Qi， causing viral infections. The struggle between healthy Qi and pathogenic Qi causes immunity-inflammation imbalance， leading to the onset of viral pneumonia. Inflammatory damage causes persistent accumulation of phlegm and stasis， leading to the progression of viral pneumonia. The cytokine storm causes immunodepletion， leading to the excess of pathogenic Qi and diminution of healthy Qi and the deterioration of viral pneumonia. After the recovery from viral pneumonia， there is a long-term imbalance between immunity and micro-inflammation， which results in healthy Qi deficiency and pathogenic Qi lingering. Healthy Qi deficiency and pathogenic Qi excess act as common core causes of pneumonia caused by different respiratory viruses. Clinical treatment should emphasize both replenishing healthy Qi and eliminating pathogenic Qi， helping to restore the balance between healthy Qi and pathogenic Qi as well as between immunity and inflammation， thus promoting the recovery of patients from viral pneumonia. According to the TCM theory of healthy Qi and pathogenic Qi， this article summarizes the immunity-inflammation mechanisms at different stages of viral pneumonia， and explores the application of the method of replenishing healthy Qi and eliminating pathogenic Qi in viral pneumonia. The aim is to probe into the scientific connotation of the TCM theory of healthy Qi and pathogenic Qi in viral pneumonia and provide ideas for the clinical application of the method of replenishing healthy Qi and eliminating pathogenic Qi to assist in the treatment of viral pneumonia.

ObjectiveTo explore the mechanism of Yishen Huashi granules in alleviating renal tubular epithelial cell injury and relieving diabetic kidney disease by regulating the mitogen-activated protein kinase （MAPK） signaling pathway. MethodsThe db/db mice of 12 weeks old were randomly assigned into model ， dapagliflozin （1.6 mg·kg^-1）， and Yishen Huashi granules （4.7 g·kg^-1）， and db/m mice were used as the control group. The general conditions of mice were observed， and fasting blood glucose and 24-h urinary protein and albumin-to-creatinine ratio （ACR） were measured at weeks 0 and 12 of administration. After 12 weeks of treatment， the levels of serum creatinine （SCr）， blood urea （UREA）， triglycerides （TG）， total cholesterol （TC）， and low density lipoprotein （LDL） were measured. The pathological changes in the renal tissue were observed by hematoxylin-eosin （HE） staining， Periodic acid-Schiff （PAS） staining， Mallory staining， and transmission electron microscopy. Real-time PCR was employed to determine the mRNA levels of monocyte chemotactic protein-1 （MCP-1） and CC chemokine receptor-2 （CCR2） in the renal tissue of mice. The immunohistochemical assay was employed to examine the expression of p38， phospho-p38 （p-p38）， MCP-1， and CCR2 in the renal tissue of mice. Western blotting was employed to measure the protein levels of p-p38， p38， MCP-1， and CCR2 in the renal tissue of mice.HK-2 cells cultured in vitro were grouped as follows： negative control， high glucose（30 mmol·L^-1）， Yishen Huashi granule-containing serum， and SB203580. After 48 h of cell culture in each group， RNA were extracted and the levels of MCP-1， and CCR2 mRNA were determined by Real-time PCR，proteins were extracted and the levels of p38， p-p38， MCP-1， and CCR2 were determined by Western blot. ResultsThe in vivo experiments showed that before treatment， other groups had higher body weight， blood glucose level， 24 h urinary protein， and ACR than the control group （P<0.05，P<0.01）. After 12 weeks of treatment， compared with the model group， the Yishen Huashi granules group showed improved general conditions， a decreasing trend in body weight， lowered levels of blood glucose， 24-h urinary protein， and ACR （P<0.01）， reduced SCr and UREA （P<0.01）， and declined levels of TC， TG， and LDL （P<0.05，P<0.01）. Compared with the model group， the Yishen Huashi granules group showed alleviated damage and interstitial fibrosis in the renal tissue as well as reductions in glomerular foot process fusion and basement membrane thickening. Moreover， the Yishen Huashi granules group showed down-regulated mRNA levels of MCP-1 and CCR2 （P<0.01）， reduced positive expression of p-p38， MCP-1， and CCR2 （P<0.01）， and down-regulated protein levels of p-p38/p38， MCP-1， and CCR2 （P<0.05） in the renal tissue. The cell experiment showed that compared with the high glucose group， the Yishen Huashi granule-containing serum group showcased down-regulated mRNA levels of MCP-1 and CCR2 （P<0.01） and down-regulated protein levels of p-p38/p38， MCP-1， and CCR2（P<0.05，P<0.01）. ConclusionYishen Huashi granules can regulate glucose-lipid metabolism， reduce 24 h urinary protein and ACR， improve the renal function， alleviate the renal tubule injury caused by high glucose， and protect renal tubule epithelial cells in db/db mice by reducing MCP-1/CCR2 activation via the p38 MAPK signaling pathway.

ObjectiveThe controllability changes of structural brain network were explored based on the control and brain network theory in young smokers, this may reveal that the controllability indicators can serve as a powerful factor to predict the sleep status in young smokers. MethodsFifty young smokers and 51 healthy controls from Inner Mongolia University of Science and Technology were enrolled. Diffusion tensor imaging (DTI) was used to construct structural brain network based on fractional anisotropy (FA) weight matrix. According to the control and brain network theory, the average controllability and the modal controllability were calculated. Two-sample t-test was used to compare the differences between the groups and Pearson correlation analysis to examine the correlation between significant average controllability and modal controllability with Fagerström Test of Nicotine Dependence (FTND) in young smokers. The nodes with the controllability score in the top 10% were selected as the super-controllers. Finally, we used BP neural network to predict the Pittsburgh Sleep Quality Index (PSQI) in young smokers. ResultsThe average controllability of dorsolateral superior frontal gyrus, supplementary motor area, lenticular nucleus putamen, and lenticular nucleus pallidum, and the modal controllability of orbital inferior frontal gyrus, supplementary motor area, gyrus rectus, and posterior cingulate gyrus in the young smokers’ group, were all significantly different from those of the healthy controls group (P<0.05). The average controllability of the right supplementary motor area (SMA.R) in the young smokers group was positively correlated with FTND (r=0.393 0, P=0.004 8), while modal controllability was negatively correlated with FTND (r=-0.330 1, P=0.019 2). ConclusionThe controllability of structural brain network in young smokers is abnormal. which may serve as an indicator to predict sleep condition. It may provide the imaging evidence for evaluating the cognitive function impairment in young smokers.

ObjectiveINF2 is a member of the formins family. Abnormal expression and regulation of INF2 have been associated with the progression of various tumors, but the expression and role of INF2 in hepatocellular carcinoma (HCC) remain unclear. HCC is a highly lethal malignant tumor. Given the limitations of traditional treatments, this study explored the expression level, clinical value and potential mechanism of INF2 in HCC in order to seek new therapeutic targets. MethodsIn this study, we used public databases to analyze the expression of INF2 in pan-cancer and HCC, as well as the impact of INF2 expression levels on HCC prognosis. Quantitative real time polymerase chain reaction (RT-qPCR), Western blot, and immunohistochemistry were used to detect the expression level of INF2 in liver cancer cells and human HCC tissues. The correlation between INF2 expression and clinical pathological features was analyzed using public databases and clinical data of human HCC samples. Subsequently, the effects of INF2 expression on the biological function and Drp1 phosphorylation of liver cancer cells were elucidated through in vitro and in vivo experiments. Finally, the predictive value and potential mechanism of INF2 in HCC were further analyzed through database and immunohistochemical experiments. ResultsINF2 is aberrantly high expression in HCC samples and the high expression of INF2 is correlated with overall survival, liver cirrhosis and pathological differentiation of HCC patients. The expression level of INF2 has certain diagnostic value in predicting the prognosis and pathological differentiation of HCC. In vivo and in vitro HCC models, upregulated expression of INF2 triggers the proliferation and migration of the HCC cell, while knockdown of INF2 could counteract this effect. INF2 in liver cancer cells may affect mitochondrial division by inducing Drp1 phosphorylation and mediate immune escape by up-regulating PD-L1 expression, thus promoting tumor progression. ConclusionINF2 is highly expressed in HCC and is associated with poor prognosis. High expression of INF2 may promote HCC progression by inducing Drp1 phosphorylation and up-regulation of PD-L1 expression, and targeting INF2 may be beneficial for HCC patients with high expression of INF2.

ObjectiveTo investigate the influence of entecavir （ETV） versus tenofovir alafenamide fumarate （TAF） on renal function in previously untreated patients with chronic hepatitis B （CHB）. MethodsA retrospective analysis was performed for the clinical data of 167 previously untreated CHB patients who received ETV or TAF treatment for at least 48 weeks at the outpatient service of Department of Infectious Diseases in The First Affiliated Hospital of Nanchang University from September 2019 to November 2023， and according to the antiviral drug used， they were divided into ETV group with 117 patients and TAF group with 50 patients. In order to balance baseline clinical data， propensity score matching （PSM） was used for matching and analysis at a ratio of 2∶1， and the two groups were compared in terms of estimated glomerular filtration rate （eGFR） and the incidence rate of abnormal renal function at week 48. According to eGFR at week 48， the patients were divided into normal renal function group and abnormal renal function group. The independent-samples t test or the Mann-Whitney U test was used for comparison of continuous data between two groups， and the chi-square test or the Fisher’s exact test was used for comparison of categorical data between two groups. The multivariate Logistic regression analysis was used to investigate the influencing factors for abnormal renal function， and the receiver operating characteristic （ROC） curve was used to assess the performance of each indicator in predicting abnormal renal function. The Kaplan-Meier method was used to analyze the cumulative incidence rate of abnormal renal function， and the log-rank test was used for comparison. The analysis of variance with repeated measures was used to compare the dynamic changes of eGFR during antiviral therapy in CHB patients. ResultsAfter PSM matching， there were 100 patients in the ETV group and 50 patients in the TAF group. There were no significant differences in baseline clinical data between the ETV group and the TAF group （all P>0.05）， with an eGFR level of 112.29±9.92 mL/min/1.73 m² in the ETV group and 114.72±12.15 mL/min/1.73 m² in the TAF group. There was a reduction in eGFR from baseline to week 48 in both groups， and compared with the TAF group at week 48， the ETV group had a significantly lower eGFR （106.42±14.12 mL/min/1.73 m² vs 112.25±13.44 mL/min/1.73 m²， t=-2.422， P=0.017） and a significantly higher incidence rate of abnormal renal function （17.00% vs 4.00%， χ²=5.092， P=0.024）. After the patients were divided into normal renal function group with 131 patients and abnormal renal function group with 19 patients， the univariate analysis showed that there were significant differences between the two groups in age （Z=-2.039， P=0.041）， treatment drug （ETV/TAF） （χ²=5.092， P=0.024）， and baseline eGFR level （t=4.023， P<0.001）， and the multivariate Logistic regression analysis showed that baseline eGFR （odds ratio ［OR］=0.896， 95% confidence interval ［CI］： 0.841 — 0.955， P<0.001） and treatment drug （OR=5.589， 95%CI： 1.136 — 27.492， P=0.034） were independent influencing factors for abnormal renal function. Baseline eGFR had an area under the ROC curve of 0.781 in predicting abnormal renal function in CHB patients， with a cut-off value of 105.24 mL/min/1.73 m²， a sensitivity of 73.68%， and a specificity of 82.44%. The Kaplan-Meier curve analysis showed that the patients with baseline eGFR≤105.24 mL/min/1.73 m² had a significantly higher cumulative incidence rate of abnormal renal function than those with baseline eGFR>105.24 mL/min/1.73 m² （χ²=22.330， P<0.001）， and the ETV group had a significantly higher cumulative incidence rate of abnormal renal function than the TAF group （χ²=4.961， P=0.026）. With the initiation of antiviral therapy， both the ETV group and the TAF group had a significant reduction in eGFR （F=5.259， P<0.001）， but the ETV group only had a significant lower level of eGFR than the TAF group at week 48 （t=-2.422， P=0.017）； both the baseline eGFR≤105.24 mL/min/1.73 m² group and the baseline eGFR>105.24 mL/min/1.73 m² group had a significant reduction in eGFR （F=5.712， P<0.001）， and there was a significant difference in eGFR between the two groups at baseline and weeks 12， 24， 36， and 48 （t=-13.927， -9.780， -8.835， -9.489， and -8.953， all P<0.001）. ConclusionFor CHB patients initially treated with ETV or TAF， ETV antiviral therapy has a higher risk of renal injury than TAF therapy at week 48.

The purpose of this paper is to explore the decoction and dosing methods of rhubarb root and rhizome in classical prescriptions and to provide a reference basis for the clinical use of rhubarb root and rhizome. By collating the relevant classical prescriptions of rhubarb root and rhizome in Shanghan Lun and Jingui Yaolüe, the relationship between its decoction and dosing methods and the syndrome was analyzed. The decoction of rhubarb root and rhizome in classical prescriptions can be divided into three categories: simultaneous decoction, decoction later, and other methods (impregnation in Mafei decoction, decoction with water from the well spring first taken in the morning, and pills). If it enters the blood level or wants to slow down, rhubarb root and rhizome should be decocted at the same time with other drugs. If it enters the qi level and wants to speed up, rhubarb root and rhizome should be decocted later. If it wants to upwardly move, rhubarb root and rhizome should be immersed in Mafei decoction. If it wants to suppress liver yang, rhubarb root and rhizome should be decocted with water from the well spring first taken in the morning. If the disease is prolonged, rhubarb root and rhizome should be taken in pill form. The dosing methods of rhubarb root and rhizome can be divided into five categories: draught, twice, three times, before meals, and unspecified. For acute and serious illnesses with excess of pathogenic qi and adequate vital qi, we choose draught. For gastrointestinal diseases, we choose to take the medicine twice. For achieving a moderate and long-lasting effect, we choose to take the medicine three times. If the disease is located in the lower part of the heart and abdomen, we choose to take it before meals. The use of rhubarb root and rhizome in clinical practice requires the selection of the appropriate decoction and dosing methods according to the location of the disease, the severity of the disease, the patient′s constitution, and the condition after taking the medicine.

Collagen is a major structural protein in the matrix of animal cells and the most widely distributed and abundant functional protein in mammals. Collagen’s good biocompatibility, biodegradability and biological activity make it a very valuable biomaterial. According to the source of collagen, it can be broadly categorized into two types: one is animal collagen; the other is recombinant collagen. Animal collagen is mainly extracted and purified from animal connective tissues by chemical methods, such as acid, alkali and enzyme methods, etc. Recombinant collagen refers to collagen produced by gene splicing technology, where the amino acid sequence is first designed and improved according to one’s own needs, and the gene sequence of improved recombinant collagen is highly consistent with that of human beings, and then the designed gene sequence is cloned into the appropriate vector, and then transferred to the appropriate expression vector. The designed gene sequence is cloned into a suitable vector, and then transferred to a suitable expression system for full expression, and finally the target protein is obtained by extraction and purification technology. Recombinant collagen has excellent histocompatibility and water solubility, can be directly absorbed by the human body and participate in the construction of collagen, remodeling of the extracellular matrix, cell growth, wound healing and site filling, etc., which has demonstrated significant effects, and has become the focus of the development of modern biomedical materials. This paper firstly elaborates the structure, type, and tissue distribution of human collagen, as well as the associated genetic diseases of different types of collagen, then introduces the specific process of producing animal source collagen and recombinant collagen, explains the advantages of recombinant collagen production method, and then introduces the various systems of expressing recombinant collagen, as well as their advantages and disadvantages, and finally briefly introduces the application of animal collagen, focusing on the use of animal collagen in the development of biopharmaceutical materials. In terms of application, it focuses on the use of animal disease models exploring the application effects of recombinant collagen in wound hemostasis, wound repair, corneal therapy, female pelvic floor dysfunction (FPFD), vaginal atrophy (VA) and vaginal dryness, thin endometritis (TE), chronic endometritis (CE), bone tissue regeneration in vivo, cardiovascular diseases, breast cancer (BC) and anti-aging. The mechanism of action of recombinant collagen in the treatment of FPFD and CE was introduced, and the clinical application and curative effect of recombinant collagen in skin burn, skin wound, dermatitis, acne and menopausal urogenital syndrome (GSM) were summarized. From the exploratory studies and clinical applications, it is evident that recombinant collagen has demonstrated surprising effects in the treatment of all types of diseases, such as reducing inflammation, promoting cell proliferation, migration and adhesion, increasing collagen deposition, and remodeling the extracellular matrix. At the end of the review, the challenges faced by recombinant collagen are summarized: to develop new recombinant collagen types and dosage forms, to explore the mechanism of action of recombinant collagen, and to provide an outlook for the future development and application of recombinant collagen.