Nanobodies(Nb)have become novel probes for PET imaging instead of traditional antibodies,which have broad application prospects due to advantages of small molecular weight,strong stability and permeability,passing through the blood-brain barrier and low immunogenicity.The research progresses of structural characteristics of Nb,labeling methods of positron isotopes and application of labeled products in PET imaging were reviewed in this article.

Nanobodies(Nb)have become novel probes for PET imaging instead of traditional antibodies,which have broad application prospects due to advantages of small molecular weight,strong stability and permeability,passing through the blood-brain barrier and low immunogenicity.The research progresses of structural characteristics of Nb,labeling methods of positron isotopes and application of labeled products in PET imaging were reviewed in this article.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in healthcare facilities in major regions of China in 2023.Methods Clinical isolates collected from 73 hospitals across China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2023 Clinical & Laboratory Standards Institute (CLSI) breakpoints.Results A total of 445199 clinical isolates were collected in 2023,of which 29.0％ were gram-positive and 71.0％ were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species (excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi) (MRSA,MRSE and MRCNS) was 29.6％,81.9％ and 78.5％,respectively.Methicillin-resistant strains showed significantly higher resistance rates to most antimicrobial agents than methicillin-susceptible strains (MSSA,MSSE and MSCNS).Overall,92.9％ of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 91.4％ of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis had significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 93.1％ in the isolates from children and and 95.9％ in the isolates from adults.The resistance rate to carbapenems was lower than 15.0％ for most Enterobacterales species except for Klebsiella,22.5％ and 23.6％ of which were resistant to imipenem and meropenem,respectively .Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.6％ to 10.0％.The resistance rate to imipenem and meropenem was 21.9％ and 17.4％ for Pseudomonas aeruginosa,respectively,and 67.5％ and 68.1％ for Acinetobacter baumannii,respectively.Conclusions Increasing resistance to the commonly used antimicrobial agents is still observed in clinical bacterial isolates.However,the prevalence of important crabapenem-resistant organisms such as crabapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a slightly decreasing trend.This finding suggests that strengthening bacterial resistance surveillance and multidisciplinary linkage are important for preventing the occurrence and development of bacterial resistance.

Objective To investigate the geographical distribution and seasonal fluctuations of visceral leishmaniasis vectors sandflies in Henan Province in 2023, so as to provide insights into the prevention and control of visceral leishmaniasis vectors. Methods A total of 23 counties (districts) were sampled from 18 cities of Henan Province from May to September, 2023 as sandfly surveillance sites, and sandflies were captured using human capture and light trapping methods. Following morphological identification, the changes in the sandfly density were calculated at different months and in different breeding habitats. Results A total of 406 light traps were set at sandfly surveillance sites in Henan Province from May to September, 2023, and a total of 3 137 female sandlies were captured, with an average density of 7.73 sandlies/(light·night). A total of 1 494 Phlebotomus chinensis sandflies were captured, including 1 222 female sandflies, with an average density of 3.01 sandflies/(light·night), and the highest density of P. chinensis was found in Gongyi City [17.00 sandflies/(light·night)]. A total of 5 544 sandflies were captured using the human capture method, including 230 P. chinensis, and the density of P. chinensis appeared a unimodal distribution, with a peak in early July [5.81 sandflies/(light·night)]. Among different breeding habitats, the highest P. chinensis density was detected in pigpens [4.50 sandflies/(light·night)]. Conclusions P. chinensis was predominantly distributed in hilly areas of northern and central-western Henan Province in 2023, and the sandfly density appeared a unimodal distribution. Intensified monitoring of visceral leishmaniasis vectors is recommended.

Objective To construct a universal influenza mRNA vaccine and evaluate its immunogenicity.Methods The antigen sequence of hemagglutinin(HA),nucleoprotein(NP)and matrix protein 2 ectodomain(M2e)in influenza A/California/04/2009 was optimized.HA,NP and 3 tandem M2e(3M2e)were cloned into pcDNA3.1 vector,respectively.Then the mRNAs were synthesized by linearization,in vitro transcription,enzymatic capping and enzymatic tailing,and named as mRNA-HA,mRNA-NP and mRNA-3M2e,respectively.The protein expression of the 3 kinds of mRNAs in 293T cells was detected by immunofluorescence assay.Comb-mRNA vaccine was prepared by enveloped mRNA-HA,mRNA-NP and mRNA-3M2e with lipid nanoparticles,respectively,and the particle size and potential were identified.Twenty-eight 6-week-old female BALB/c mice(18～22 g)were randomly divided into LNP group(n=14)and Comb-mRNA group(n=14).Hemagglutination inhibition(HI)method and microneutralization(MN)test were used to evaluate the serum antibody titer induced by Comb-mRNA vaccines.The mice were infected by 5LD50 wild-type H1 N1 influenza virus to evaluate the protective efficacy.Results The mRNA-HA,mRNA-NP and mRNA-3M2e were successfully constructed,and the 3 mRNAs could be expressed in 293T cells.The average size of mRNA encapsulated by lipid nanoparticles was 119.53±6.5 nm,and the average potential was-8.23±1.3 mV.The geometric mean titer(GMT)of HI and MN in the Comb-mRNA group were 179.6 and 201.6,compared with the LNP group.The ratio of IFN-γ+CD4+/CD8+Tcells was increased.The Comb-mRNA group could provide protection against 5LD50 wild type influenza H1 N1 virus after 2 weeks of booster immunization.Conclusion Comb-mRNA,an influenza vaccine candidate,can induce immune responses and protect mice from influenza virus challenge.

Objective To investigate the correlation between the expression level of glypican-3(GPC3)and the immune therapy response in clinical liver cancer patients.Methods Clinical data of 232 liver cancer immunotherapy response/tolerance group patients from January 2019 to May 2023 at the General Hospital of the People's Liberation Army were collected,and the correlation between GPC3 expression levels and the efficacy of immunotherapy in liver cancer patients was statistically analyzed;TCGA database validation of immune cell infiltration in GPC3 high and low expression groups of liver cancer patients;Further,real-time fluorescence quantitative PCR(qPCR)and immunohistochemical staining methods were used to detect the expression of GPC3 and immune cell infiltration in paired tissues of liver cancer immunotherapy response/tolerance group patients,and multi-color immunofluorescence was applied to detect the expression of GPC3 and related molecules.Results Clinical evidence shows that the GPC3 positive group of liver cancer patients has a low response rate to immunotherapy.Univariate/multivariate analysis results indicate that GPC3 is an independent risk factor for tumor recurrence after liver cancer immunotherapy;The analysis of the TCGA database revealed that high expression of GPC3 in liver cancer tissue leads to increased infiltration of regulatory T cells(Tregs);Paired tissue testing of liver cancer patients and adjacent tissues revealed that the immunotherapy effect was worse in the GPC3 high expression group,and Tregs cell infiltration increased,consistent with the results of database analysis.The TCGA database analysis results showed that GPC3 was positively correlated with CCL20 and its ligand CCR6,and the multi-color immunohistochemistry results were consistent with the database analysis results.Conclusion GPC3 is highly expressed in tumor tissues of liver cancer patients and is positively correlated with immune therapy tolerance in liver cancer.GPC3 regulates Tregs cell infiltration through the CCL20-CCR6 signaling axis and is expected to serve as a biomarker for predicting the efficacy of immune therapy in clinical liver cancer patients.

Objective To investigate the correlation between the expression level of glypican-3(GPC3)and the immune therapy response in clinical liver cancer patients.Methods Clinical data of 232 liver cancer immunotherapy response/tolerance group patients from January 2019 to May 2023 at the General Hospital of the People's Liberation Army were collected,and the correlation between GPC3 expression levels and the efficacy of immunotherapy in liver cancer patients was statistically analyzed;TCGA database validation of immune cell infiltration in GPC3 high and low expression groups of liver cancer patients;Further,real-time fluorescence quantitative PCR(qPCR)and immunohistochemical staining methods were used to detect the expression of GPC3 and immune cell infiltration in paired tissues of liver cancer immunotherapy response/tolerance group patients,and multi-color immunofluorescence was applied to detect the expression of GPC3 and related molecules.Results Clinical evidence shows that the GPC3 positive group of liver cancer patients has a low response rate to immunotherapy.Univariate/multivariate analysis results indicate that GPC3 is an independent risk factor for tumor recurrence after liver cancer immunotherapy;The analysis of the TCGA database revealed that high expression of GPC3 in liver cancer tissue leads to increased infiltration of regulatory T cells(Tregs);Paired tissue testing of liver cancer patients and adjacent tissues revealed that the immunotherapy effect was worse in the GPC3 high expression group,and Tregs cell infiltration increased,consistent with the results of database analysis.The TCGA database analysis results showed that GPC3 was positively correlated with CCL20 and its ligand CCR6,and the multi-color immunohistochemistry results were consistent with the database analysis results.Conclusion GPC3 is highly expressed in tumor tissues of liver cancer patients and is positively correlated with immune therapy tolerance in liver cancer.GPC3 regulates Tregs cell infiltration through the CCL20-CCR6 signaling axis and is expected to serve as a biomarker for predicting the efficacy of immune therapy in clinical liver cancer patients.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in healthcare facilities in major regions of China in 2023.Methods Clinical isolates collected from 73 hospitals across China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2023 Clinical & Laboratory Standards Institute (CLSI) breakpoints.Results A total of 445199 clinical isolates were collected in 2023,of which 29.0％ were gram-positive and 71.0％ were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species (excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi) (MRSA,MRSE and MRCNS) was 29.6％,81.9％ and 78.5％,respectively.Methicillin-resistant strains showed significantly higher resistance rates to most antimicrobial agents than methicillin-susceptible strains (MSSA,MSSE and MSCNS).Overall,92.9％ of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 91.4％ of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis had significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 93.1％ in the isolates from children and and 95.9％ in the isolates from adults.The resistance rate to carbapenems was lower than 15.0％ for most Enterobacterales species except for Klebsiella,22.5％ and 23.6％ of which were resistant to imipenem and meropenem,respectively .Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.6％ to 10.0％.The resistance rate to imipenem and meropenem was 21.9％ and 17.4％ for Pseudomonas aeruginosa,respectively,and 67.5％ and 68.1％ for Acinetobacter baumannii,respectively.Conclusions Increasing resistance to the commonly used antimicrobial agents is still observed in clinical bacterial isolates.However,the prevalence of important crabapenem-resistant organisms such as crabapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a slightly decreasing trend.This finding suggests that strengthening bacterial resistance surveillance and multidisciplinary linkage are important for preventing the occurrence and development of bacterial resistance.

Humans ; Asthma/drug therapy* ; Biological Therapy

Due to the insufficient long-term protection and significant efficacy reduction to new variants of current COVID-19 vaccines, the epidemic prevention and control are still challenging. Here, we employ a capsid and antigen structure engineering (CASE) strategy to manufacture an adeno-associated viral serotype 6-based vaccine (S663V-RBD), which expresses trimeric receptor binding domain (RBD) of spike protein fused with a biological adjuvant RS09. Impressively, the engineered S663V-RBD could rapidly induce a satisfactory RBD-specific IgG titer within 2 weeks and maintain the titer for more than 4 months. Compared to the licensed BBIBP-CorV (Sinopharm, China), a single-dose S663V-RBD induced more endurable and robust immune responses in mice and elicited superior neutralizing antibodies against three typical SARS-CoV-2 pseudoviruses including wild type, C.37 (Lambda) and B.1.617.2 (Delta). More interestingly, the intramuscular injection of S663V-RBD could overcome pre-existing immunity against the capsid. Given its effectiveness, the CASE-based S663V-RBD may provide a new solution for the current and next pandemic.