Membrane proteins are integral components of cellular membranes, accounting for approximately 30% of the mammalian proteome and serving as targets for 60% of FDA-approved drugs. They are critical to both physiological functions and disease mechanisms. Their functional protein-protein interactions form the basis for many physiological processes, such as signal transduction, material transport, and cell communication. Membrane protein interactions are characterized by membrane environment dependence, spatial asymmetry, weak interaction strength, high dynamics, and a variety of interaction sites. Therefore, in situ analysis is essential for revealing the structural basis and kinetics of these proteins. This paper introduces currently available in situ analytical techniques for studying membrane protein interactions and evaluates the characteristics of each. These techniques are divided into two categories: label-based techniques (e.g., co-immunoprecipitation, proximity ligation assay, bimolecular fluorescence complementation, resonance energy transfer, and proximity labeling) and label-free techniques (e.g., cryo-electron tomography, in situ cross-linking mass spectrometry, Raman spectroscopy, electron paramagnetic resonance, nuclear magnetic resonance, and structure prediction tools). Each technique is critically assessed in terms of its historical development, strengths, and limitations. Based on the authors’ relevant research, the paper further discusses the key issues and trends in the application of these techniques, providing valuable references for the field of membrane protein research. Label-based techniques rely on molecular tags or antibodies to detect proximity or interactions, offering high specificity and adaptability for dynamic studies. For instance, proximity ligation assay combines the specificity of antibodies with the sensitivity of PCR amplification, while proximity labeling enables spatial mapping of interactomes. Conversely, label-free techniques, such as cryo-electron tomography, provide near-native structural insights, and Raman spectroscopy directly probes molecular interactions without perturbing the membrane environment. Despite advancements, these methods face several universal challenges: (1) indirect detection, relying on proximity or tagged proxies rather than direct interaction measurement; (2) limited capacity for continuous dynamic monitoring in live cells; and (3) potential artificial influences introduced by labeling or sample preparation, which may alter native conformations. Emerging trends emphasize the multimodal integration of complementary techniques to overcome individual limitations. For example, combining in situ cross-linking mass spectrometry with proximity labeling enhances both spatial resolution and interaction coverage, enabling high-throughput subcellular interactome mapping. Similarly, coupling fluorescence resonance energy transfer with nuclear magnetic resonance and artificial intelligence (AI) simulations integrates dynamic structural data, atomic-level details, and predictive modeling for holistic insights. Advances in AI, exemplified by AlphaFold’s ability to predict interaction interfaces, further augment experimental data, accelerating structure-function analyses. Future developments in cryo-electron microscopy, super-resolution imaging, and machine learning are poised to refine spatiotemporal resolution and scalability. In conclusion, in situ analysis of membrane protein interactions remains indispensable for deciphering their roles in health and disease. While current technologies have significantly advanced our understanding, persistent gaps highlight the need for innovative, integrative approaches. By synergizing experimental and computational tools, researchers can achieve multiscale, real-time, and perturbation-free analyses, ultimately unraveling the dynamic complexity of membrane protein networks and driving therapeutic discovery.

In recent years, the development of single-cell sequencing technology has significantly advanced our understanding of single-cell genomics and transcriptomics. However, the study of proteomics, directly related to single-cell life processes, has been limited by slow technological progress. With advancements in sample preparation techniques and chromatography-mass spectrometry instruments, the analytical sensitivity of single-cell proteomics (SCP) has markedly improved. In this review, we thoroughly examine the development of SCP and its applications in life sciences. Regarding sample preparation, various methods such as gentle acoustic dispensing, microfluidic chips, and laser microdissection have been developed for single-cell sorting, gradually transitioning from multi-step to one-step processing, thereby reducing sample loss. In mass spectrometry, both label-free quantification and methods based on isotopic and isobaric labeling have been extensively explored, each with their own technical strengths and weaknesses. SCP has unveiled new biological insights in early embryonic cell development, stem cell differentiation, and spatial heterogeneity of liver tissues. Finally, we summarize the current challenges facing SCP technology, including detection throughput, cost, and data analysis complexity, while envisioning its future directions and emphasizing its broad potential in basic research and clinical applications.

This paper aimed to study the effect of Erjing Pills on the improvement of neuroinflammation of rats with Alzheimer's di-sease(AD) induced by the combination of D-galactose and Aβ_(25-35) and its mechanism. SD rats were randomly divided into a sham group, a model control group, a positive drug group(donepezil, 1 mg·kg~(-1)), an Erjing Pills high-dose group(9.0 g·kg~(-1)), and an Erjing Pills low-dose group(4.5 g·kg~(-1)), with 14 rats each group. To establish the rat model of AD, Erjing Pills were intragastrically administrated to rats for 5 weeks after 2 weeks of D-galactose injection. D-galactose was intraperitoneally injected into rats for 3 weeks, and then Aβ_(25-35) was injected into the bilateral hippocampus. The new object recognition test was used to evaluate the learning and memory ability of rats after 4 weeks of intragastric administration. Tissues were acquired 24 h after the last administration. The immunofluorescence method was used to detect the activation of microglia in the brain tissue of rats. The positive expressions of Aβ_(1-42) and phosphory protein Tau~(404)(p-Tau~(404)) in the CA1 area of the hippocampus were detected by immunohistochemistry. The levels of inflammatory factors interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and interleukin-6(IL-6) in the brain tissue were determined by enzyme-linked immunosorbent assay(ELISA). Toll-like receptor 4(TLR4)/nuclear factor kappa B(NF-κB)/nucleotide-binding oligomerization domain-like receptors 3(NLRP3) pathway-associated proteins in the brain tissue were determined by Western blot. The results showed that as compared with the sham group, the new object recognition index of rats in the model control group decreased significantly, the deposition of Aβ_(1-42) and p-Tau~(404) positive protein in the hippocampus increased significantly, and the levels of microglia activation increased significantly in the dentate gyrus. The levels of IL-1β, TNF-α, and IL-6 in the hippocampus of the model control group increased significantly, and the expression levels of TLR4, p-NF-κB p65/NF-κB p65, p-IκBα/IκBα, and NLRP3 proteins in the hippocampus increased significantly. Compared with the model control group, the Erjing Pill groups enhanced the new object recognition index of rats, decreased the deposition of Aβ_(1-42) and the expression of p-Tau~(404) positive protein in the hippocampus, inhibited the activation of microglia in the dentate gyrus, reduced the levels of inflammatory factors IL-1β, TNF-α, and IL-6 in the hippocampus, and down-regulated the expression levels of TLR4, p-NF-κB P65/NF-κB P65, p-IκBα/IκBα, and NLRP3 proteins in the hippocampus. In conclusion, Erjing Pills can improve the learning and memory ability of the rat model of AD presumably by improving the activation of microglia, reducing the expression levels of neuroinflammatory factors IL-1β, TNF-α, and IL-6, inhibiting the TLR4/NF-κB/NLRP3 neuroinflammation pathway, and decreasing hippocampal deposition of Aβ and expression of p-Tau, thereby restoring the hippocampal morphological structure.
Animals ; Rats ; Rats, Sprague-Dawley ; NF-kappa B ; NF-KappaB Inhibitor alpha ; NLR Family, Pyrin Domain-Containing 3 Protein ; Galactose ; Interleukin-6 ; Neuroinflammatory Diseases ; Toll-Like Receptor 4 ; Tumor Necrosis Factor-alpha

Aim To investigate the role of FKBP38 in inhibiting apoptosis in a rotenone-induced Parkinson's disease(PD)cell model. Methods In vivo experiments:MPTP-induced PD in vivo models were constructed,and the expressions of α-synuclein,TH and FKBP38 in brains of PD mice were detected. In vitro experiments:Dopaminergic neuron MN9D cells were stimulated with rotenone to construct an in vitro model of PD; Western blot was used to detect the expression levels of α-synuclein,TH,Tom20 and FKBP38 in PD in vitro model; FKBP38 lentivirus was transferred into MN9D cells to construct stable overexpression and FKBP38 knockdown cell lines; CCK-8 assay was used to detect the cell viability of FKBP38 overexpression and knockdown cells stimulated by rotenone; Western blot was used to detect anti-apoptotic protein Bcl-2 and apoptosis protein in PD cell model expression levels of Bax. Results The expression level of FKBP38 was significantly down-regulated in both in vitro and in vivo models of PD(P<0.01). Knockdown of FKBP38 aggravated the decline of dopaminergic neuron cell viability caused by rotenone(P<0.05),while overexpression of FKBP38 significantly ameliorated the decline of dopaminergic neuron cell viability caused by rotenone(P<0.05). Western blot results showed that overexpression of FKBP38 could significantly up-regulate the expression level of anti-apoptotic protein Bcl-2 and increase the ratio of Bcl-2/Bax in PD dopaminergic neurons(P<0.05). Conclusion In the PD cell model regulation of FKBP38 can improve the apoptosis of dopaminergic neurons.

Objective: To estimate the incidence of HIV-1 infection in men who have sex with men (MSM) in key areas of China through HIV-1 limiting antigen avidity enzyme immunoassay (LAg-Avidity EIA), analyze the deviation from the actual results and identify influencing factors, and provided reference for improving the accuracy of estimation results. Methods: Based on the principle of the cohort randomized study design, 20 cities were selected in China based on population size and the number of HIV-positive MSM. The sample size was estimated to be 700 according to the HIV-1 infection rate in MSM. MSM mobile phone app. was used to establish a detection appointment and questionnaire system, and the baseline cross-sectional survey was conducted from April to November 2019. LAg-Avidity EIA was used to identify the recent infected samples. The incidence of HIV-1 infection was calculated and then adjusted based on the estimation formula designed by WHO. The influencing factors were identified by analyzing the sample collection and detection processes. Results: Among the 10 650 blood samples from the participants, 799 were HIV-positive in initial screening, in which 198 samples (24.78%) missed during confirmation test. Only 621 samples were received by the laboratory. After excluding misreported samples, 520 samples were qualified for testing. A total of 155 samples were eventually determined as recent infection through LAg-Avidity EIA; Based on the estimation formula , the incidence of HIV-1 infection in MSM in 20 cities was 4.06% (95%CI:3.27%-4.85%), it increased to 5.53% (95%CI: 4.45%-6.60%)after the adjusting for sample missing rate. When the sample missing rate and misreporting rate were both adjusted, the incidence of HIV-1 infection in the MSM increased to 5.66% (95%CI:4.67%-6.65%). The actual incidence of HIV-1 infection in MSM in the 20 cities might be between 4.06% and 5.66%. Conclusions: Sample missing and misreporting might cause the deviation of the estimation of HIV-1 infection incidence. It is important to ensure the sample source and the quality of sample collection and detection to reduce the deviation in the estimation of HIV-1 infection incidence.
Cross-Sectional Studies ; HIV Infections/epidemiology* ; HIV-1 ; Homosexuality, Male ; Humans ; Immunoenzyme Techniques ; Incidence ; Male ; Sexual and Gender Minorities

Objective: To analyze the prevalence of dry and wet age-related macular degeneration (AMD) in patients with diabetes, hypertension and hyperlipidemia, and to analyze the risk factors for AMD. Methods: A population-based cross-sectional epidemiologic study was conducted involving 14,440 individuals. We assessed the prevalence of dry and wet AMD in diabetic and non-diabetic subjects and analyzed the risk factors for AMD. Results: The prevalence of wet AMD in diabetic and non-diabetic patients was 0.3% and 0.5%, respectively, and the prevalence of dry AMD was 17% and 16.4%, respectively. The prevalence of wet AMD in healthy, hypertensive, hyperlipidemic, and hypertensive/hyperlipidemic populations was 0.5%, 0.3%, 0.2%, and 0.7%, respectively. The prevalence of dry AMD in healthy, hypertensive, hyperlipidemic, and hypertensive/hyperlipidemic populations was 16.6%, 16.2%, 15.2%, and 17.2%, respectively. Age, sex, body mass index, and use of hypoglycemic drugs or lowering blood pressure drugs were corrected in the risk factor analysis of AMD. Diabetes, diabetes/hypertension, diabetes/hyperlipidemia, and diabetes/hypertension/hyperlipidemia were analyzed. None of the factors analyzed in the current study increased the risk for the onset of AMD. Conclusion There was no significant difference in the prevalence of wet and dry AMD among diabetic and non-diabetic subjects. Similarly, there was no significant difference in the prevalence of wet and dry AMD among subjects with hypertension and hyperlipidemia. Diabetes co-existing with hypertension and hyperlipidemia were not shown to be risk factors for the onset of dry AMD.
Cross-Sectional Studies ; Diabetes Mellitus/epidemiology* ; Humans ; Hyperlipidemias/epidemiology* ; Hypertension/epidemiology* ; Macular Degeneration/etiology* ; Risk Factors

OBJECTIVE: KRAS gene is one of the most common mutations of proto-oncogenes in human tumors, G12V is one of the most common mutation types for KRAS. It's challenging to chemically acquire the targeted drug for this mutation. Recent studies reported that this mutation peptides can form a neoepitope for T cell recognition. Our study aims to clone the T cell receptor (TCR) which specifically recognizes the neoepitope for KRAS G12V mutation and constructs TCR engineered T cells (TCR-T), and to investigate if TCR-Ts have strong antitumor response ability. METHODS: In this study, tumor infiltrating lymphocytes were obtained from one colorectal cancer patient carrying KRAS G12V mutation. Tumor-reactive TCR was obtained by single-cell RT-5' rapid-amplification of cDNA ends PCR analysis and introduced into peripheral blood lymphocytes to generate TCR-Ts. RESULTS: We obtained a high-affinity TCR sequence that specifically recognized the HLA-A^*11:01-restricted KRAS G12V_8-16 epitope: KVA11-01. KVA11-01 TCR-T could significantly kill various tumor cells such as PANC-1, SW480 and HeLa (overexpressing HLA-A^*11:01 and KRAS G12V), and secreting high levels of interferon-γ (IFN-γ). Non-specific killing experiments suggested KVA11-01 specifically recognized tumor cells expressing both mutant KRAS G12V and HLA-A^*11:01. In vivo assay, tumor inhibition experiments demonstrated that infusion of approximately 1E7 KVA11-01 TCR-T could significantly inhibit the growth of subcuta-neously transplanted tumors of PANC-1 and HeLa (overexpressing HLA-A^*11:01 and KRAS G12V) cells in nude mice. No destruction of the morphologies of the liver, spleen and brain were observed. We also found that KVA11-01 TCR-T could significantly infiltrate into tumor tissue and had a better homing ability. CONCLUSION KVA11-01 TCR-T cells can effectively target a variety of malignant tumor cells carrying KRAS G12V mutation through in vitro and in vivo assay. KVA11-01 TCR-T cells have excellent biological activity, high specificity of target antigen and homing ability into solid tumor tissue. KVA11-01 TCR-T is expected to be an effective treatment for patients with KRAS G12V mutant solid malignancies.
Animals ; DNA, Complementary ; Epitopes ; HLA-A Antigens ; Humans ; Interferon-gamma ; Mice ; Mice, Nude ; Mutation ; Neoplasms ; Proto-Oncogene Proteins p21(ras)/genetics* ; Receptors, Antigen, T-Cell/genetics*

OBJECTIVE: To explore the association between postpartum depression (PPD) and transforming growth factor-β (TGF-β) concentrations in human colostrum. METHODS: Participants were recruited from a maternal and infant cohort established in a tertiary general hospital in Guangdong Province between December, 2020 and September, 2021. In the afternoon of the second postpartum day, the women were evaluated with Edinburgh Postnatal Depression Scale (EPDS) for screening PPD (defined as a score of 10 or higher). The women with PPD were matched at a 1:1 ratio with women without PPD with maternal age difference within 5 years and the same mode of delivery. Colostrum samples were collected in morning on the third postpartum day for measurement of TGF-β concentrations using enzyme-linked immunosorbent assay (ELISA), and the association between EPDS scores and TGF-β concentrations was analyzed in the two groups. RESULTS: A total of 90 women were included in the final analysis. The mean concentrations of TGF-β1, TGF-β2 and TGF-β3 in the colostrum were 684.03 (321.22-859.25) pg/mL, 5116.50±1747.04 pg/mL and 147.84±48.68 pg/mL in women with PPD, respectively, as compared with 745.67 (596.00-964.22) pg/mL, 4912.40±1516.80 pg/mL, and 168.21±48.15 pg/mL in women without PPD, respectively. Compared with women without PPD, the women with PPD had significantly lower concentrations of TGF-β1 (P=0.026) and TGF-β3 (P=0.049) in the colostrum. Spearman correlation analysis revealed that the EPDS scores were negatively associated with the concentrations of TGF-β1 (r=-0.23, P=0.03) and TGF-β3 (r=-0.25, P=0.02) in the colostrum. CONCLUSION PPD is associated with decreased concentrations of TGF-β1 and TGF-β3 in human colostrum, suggesting the need of early PPD screening and interventions during pregnancy and the perinatal period to minimize the impact of PPD on human milk compositions.
Child, Preschool ; Cohort Studies ; Colostrum ; Depression, Postpartum/diagnosis* ; Female ; Humans ; Infant ; Postpartum Period ; Pregnancy ; Transforming Growth Factor beta1 ; Transforming Growth Factor beta2 ; Transforming Growth Factor beta3 ; Transforming Growth Factors

OBJECTIVES: To summarize the skeletal muscle magnetic resonance imaging (MRI) features of the lower limbs in common subtypes of muscular dystrophy (MD) and the experience in the application of MRI in the diagnosis of MD. METHODS: A total of 48 children with MD who were diagnosed by genetic testing were enrolled as subjects. The muscle MRI features of the lower limbs were analyzed. Cumulative fatty infiltration score was calculated for each subtype, and the correlation of cumulative fatty infiltration score with clinical indices was analyzed for Duchenne muscular dystrophy (DMD). RESULTS: DMD was characterized by the involvement of the gluteus maximus and the adductor magnus. Becker muscular dystrophy was characterized by the involvement of the vastus lateralis muscle. Limb-girdle muscular dystrophy was characterized by the involvement of the adductor magnus, the vastus intermedius, the vastus medialis, and the vastus lateralis muscle. For DMD, the cumulative fatty infiltration score of the lower limb muscles was significantly correlated with age, course of the disease, muscle strength, and motor function (P<0.05), while it was not significantly correlated with the serum creatine kinase level (P>0.05). CONCLUSIONS Different subtypes of MD have different MRI manifestations, and MRI may help with the diagnosis and assessment of MD.
Child ; Humans ; Muscular Dystrophy, Duchenne/diagnostic imaging* ; Muscular Dystrophies, Limb-Girdle/pathology* ; Muscle, Skeletal/diagnostic imaging* ; Magnetic Resonance Imaging/methods* ; Thigh/pathology*

OBJECTIVE: To observe the effect of moxibustion on Nrf2/HO-1 signaling pathway in rats with diminished ovarian reserve (DOR), and to explore the protective mechanism of moxibustion on ovarian reserve function. METHODS: Forty SD rats were randomly divided into a blank group, a model group, a moxibustion group and a hormone group, 10 rats in each group. The rats in the model group, moxibustion group and hormone group were treated with intragastric administration of tripterysium glycosides turbid liquid to prepare DOR model. The rats in the blank group were treated with intragastric administration of sodium chloride solution with the same volume, once a day for 14 days. The rats in the hormone group were treated with hormone sequential therapy for 14 days from the day of modeling; the rats in the moxibustion group were treated with moxibustion at bilateral "Shenshu" (BL 23) or "Guanyuan" (CV 4) and "Zhongwan" (CV 12) from the day of modeling, and the two groups acupoints were alternated every other day, 10 min each time, for 14 consecutive days. The estrus cycle was observed every day by vaginal exfoliated cell smear, and the estrus cycle disorder rate in each group was calculated. After the intervention, the HE staining was used to observe the histological morphology of ovaries; ELISA was used to detect the contents of follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E RESULTS: Compared with the blank group, the rate of estrus cycle disorder in the model group was increased ( CONCLUSION Moxibustion could reduce the rate of estrus cycle disorder, improve the level of serum sex hormones and antioxidant stress in DOR rats, and the mechanism may be related to the regulation of Nrf2/HO-1 signaling pathway.
Animals ; Female ; Humans ; Moxibustion ; NF-E2-Related Factor 2/metabolism* ; Ovarian Reserve ; Rats ; Rats, Sprague-Dawley ; Signal Transduction