Objective　To evaluate the non-clinical safety of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) chicken egg yolk immunoglobulin (IgY) spray by investigating the systemic and local toxicities, skin sensitization and potential eye irritation through repeated nasal and oropharyngeal administration in animals. Methods　Toxicity in ICR mice was evaluated after nasal and oropharynx drop administration of anti-SARS-CoV-2 IgY (71.04, 142.08 μg/d) once daily for 2 weeks. After SD rats were administrated with anti-SARS-CoV-2 IgY (639.35, 1 278.70, 2 557.40 μg/d) by nasal drop and oropharyngeal spray twice daily for 4 weeks, toxicity, target organs, toxicokinetics, and recovery after 4 weeks withdrawal were assessed. Active skin anaphylaxis test was used to evaluate the allergenicity after application of 0.4 mL anti-SARS-CoV-2 IgY (2 367.96 µg/mL) on backs of guinea pigs. New Zealand rabbits were given anti-SARS-CoV-2 IgY eye drops (2 367.96 µg/mL) 3 times daily for 7 d to evaluate the eye irritability. Results　No significant systemic toxicity was observed in ICR mice of either dosage group in 2 weeks, and the no observed adverse effect level (NOAEL) was 142.08 μg/d. The drug-related local irritant reaction was observed in 142.08 μg/d group, and the safe local dosage (71.04 μg/d) was 31.17 times of the clinical intended dose. The blood concentration of anti-SARS-CoV-2 IgY was under the lower limit of quantitation (0.74 μg/mL) in all SD rats of any dosage group, and no obvious systemic toxic reaction was observed. The NOAEL for SD rats (2 557.40 μg/d) was 112.20 times of the clinical intended dose, with only high-dosage group male rats presented a reversible local irritant response on nasal mucosa and tunica propria. Active skin allergic reactions in guinea pigs and eye irritation in New Zealand rabbits were both negative. Conclusions　The anti-SARS-CoV-2 IgY spray shows good safety when administered through the nasal cavity and oropharynx. At more than 100 times of human clinical highest intended dose, no obvious systemic toxicity occurs. The local irritant reaction observed in high-dosage group SD rats is recoverable. At clinical concentration, the tested product does not cause anaphylactic response in skin or irritate eyes.

Objective　To evaluate the antimicrobial susceptibility of different serogroups of Neisseria meningitidis (Nm) in Anhui Province during 2021-2023， and to provide reasonable basis for clinical treatment of epidemic cerebrospinal meningitis.Methods　Thirty-five strains of Nm isolated and cultured from epidemic cerebrospinal meningitis cases, close contacts and healthy people in Anhui Province from 2021 to 2023 were collected, and their sensitivity to 12 kinds of antimicrobial agents was assessed by E-test.Results　The sensitivity rates of 35 Nm strains to 12 drugs were 97.14% for penicillin and cefotaxime, 100.00% for ampicillin, ceftriaxone, meropenem, minocycline, azithromycin, chloramphenicol and rifampicin, 5.71% for ciprofloxacin, and 0.00% for levofloxacin and trimethoprim-sulfamethoxazole. Among them, one group B Nm insensitive to penicillin was isolated from close contact in 2022, and one serogroup nongroupable Nm insensitive to cefotaxime was isolated from healthy person in 2023.Conclusions　The 35 Nm strains isolated in Anhui Province from 2021 to 2023 are generally sensitive to penicillin, ampicillin, cefotaxime, ceftriaxone, meropenem, minocycline, azithromycin, chloramphenicol and rifampicin, partially resistant to ciprofloxacin and levofloxacin, and totally resistant to trimethoprim-sulfamethoxazole. With the increasing complexity of Nm resistance in Anhui Province, long-term monitoring of Nm resistance should be carried out to guide clinical rational drug use.

Objective　To investigate the relationship between specific activity and isoelectric point distribution of equine tetanus immunoglobulin F（ab'）₂, so as to establish a better quality characterization for optimizing the process.Methods　The isoelectric points of equine tetanus immunoglobulin F（ab'）₂ before and after immunoaffinity chromatography purification were measured by capillary isoelectric focusing（CIEF） electrophoresis, and the experimental results were statistically analyzed.Results　The isoelectric point distribution ranges of the samples before and after purification by immunoaffinity chromatography were both 4.97-9.88. The isoelectric point distribution of the purified samples was more concentrated. After purification, the propartions of peak area in the isoelectric point ranges of 6.01-7.00 and 8.01-9.00 increased compared with those before purification, with an average increase of 70% and 37%, respectively. In the isoelectric point ranges of 7.01-8.00 and 9.01-10.00, the peak area proportion decreased by 25% and 26%, respectively.Conclusion　According to the results of this study, it is speculated that the isoelectric points of the antibody with strong neutralizing activity against tetanus toxin in equine tetanus immunoglobulin F(ab')₂ may mainly be distributed in the ranges of 6.01-7.00 and 8.01-9.00.

Objective　To establish and validate the surface plasmon resonance (SPR) method for the rapid detection of antigenic content of inactivated enterovirus 71 (EV71) vaccine. Methods　Rabbit anti-EV71 antibody was coupled to the surface of a SPR chip, and the SPR chip surface signals were monitored following the binding of EV71 antigen to the antibody. EV71 national antigen standard was used to establish the SPR method for EV71 antigen content detection. The linear range, specificity, precision and accuracy of this method were verified. Six batches of EV71 vaccine bulk were used for antigen detection, and the differences between the SPR and ELISA methods were compared. Results　Rabbit anti-EV71 antibody coupled at a level of 8 037 response unit, indicating a good affinity for EV71. When the antigen content of EV71 national antigen standards ranged over 12.5-200.0 U/mL, it showed a good linear relationship to the response value of SPR analyzer, with coefficient of determination≥0.990 0. There was no cross-reactivity of the chip with Sabin strain poliovirus inactivated vaccine and PBS. The relative standard deviations (RSDs) of repeatability and intermediate precision were 1.52% and 1.54%, respectively. The accuracy recoveries were in the range of 91.70%-103.85%. A statistically significant difference was found between the SPR and ELISA for detecting the antigenic content of different batches of vaccine bulk (Z=﹣2.201， P=0.028), but the RSD was less than 15%, and the results showed a consistent trend. Conclusions　Detection method of EV71 antigen content using the SPR technique is established and validated. The method has good linearity, specificity, precision and accuracy, thus can be used for rapid antigen content detection of EV71 inactivated vaccine.

Objective　To establish a rapid, simple, and accurate method for detecting the infection titer of recombinant respiratory syncytial virus expressing the enhanced green fluorescent protein (RSV-EGFP).Methods　Utilizing an RSV-EGFP generated through reverse genetics as the subject and employing flow cytometry as the detection method, a mathematical model was developed based on the Poisson distribution for curve fitting. With this model, the viral infection titer was determined using pre-established parameters.Results　A new method for detecting RSV-EGFP infection titer by mathematical model of virus infection based on Poisson distribution and flow cytometry was successfully established. Compared with the traditional fluorescence microscope counting method, detection results of the new method had no statistically significant difference (t=0.16, P=0.879).The coefficient of variation of 6 experiments was 10.42% for the new method, while was 60.44% for fluorescence microscope counting method, showing good repeatability.Conclusion　A new method suitable for the determination of RSV-EGFP infection titer is established, which can also provide a reference for the determination of other virus infection titers.

Objective　To establish a chromogenic substrate method for the determination of residual heparin in human coagulation factor Ⅷ(FⅧ ).Methods　The chromogenic substrate method (including kinetic method and endpoint method) was established using fully automated coagulation analyzer to determine the residual heparin in FⅧ. The method was verified for specificity, linearity, accuracy, intermediate precision, quantification limit and detection range.Heparin residues in three batches of FⅧ samples were measured using the above method.Results　The specificities of the kinetic method and endpoint method were good. In the range of 0.000-0.064 international unit (IU)/mL, the concentration of heparin standard solution for 2 methods showed a good linear relationship with the logarithm of absorbance value or its change rate. The mean values of spiked recoveries were all in the range of 75%-120%. The reproducibility RSDs were all≤8%, and the intermediate precision RSDs were all≤8%. The quantification limit of kinetic method was 0.007 IU/mL, and the detection range was 0.007-0.048 IU/mL.The quantification limit of endpoint method was 0.014 IU/mL, and the detection range was 0.014-0.048 IU/mL.The heparin residues of the 3 batches of samples tested by the 2 methods were below the limit of quantification.Conclusion　The determination method of heparin residue in FⅧ is successfully developed, which has good specificity, linearity, accuracy, repeatability and intermediate precision.

Pertussis is a highly contagious acute respiratory infectious disease caused by Bordetella pertussis. Pertussis transmits predominantly through droplets and poses a significant threat to life, especially in severe cases. In recent years, pertussis resurgence has occurred globally with evolving epidemiological patterns. The prevalence of pertussis in China is also increasing. A variety of factors influence pertussis resurgence. This paper aims to systematically sort out and analyze the causes of pertussis resurgence in China, and put forward some prevention and control suggestions, providing references for preventing this type of infectious disease.

Liposomes are artificially prepared nanometer-scale spherical vesicular structures composed of phospholipids, cholesterol, surfactants, etc. Liposomes exhibit a variety of potential applications in drug delivery and vaccine development due to advantages such as flexible charge, particle size regulation and surface modification properties. In cancer therapy, liposomes have become an important tool for improving therapeutic efficacy and reducing side effects by enhancing drug targeting, improving drug biocompatibility and stability and controlling drug release. Liposomes are the key technology for improving drug delivery efficiency and enhancing the efficacy of anti-tumor treatments. This article reviews the current state of the application of liposomes in pharmaceuticals to provide reference for developing novel liposomes.

Zika virus (ZIKV), a mosquito-borne virus, may cause severe neurological symptoms upon infection. To date, the knowledge of pathogenesis underlying the early stages of ZIKV infection and its interaction with host cells is limited. The mammalian target of rapamycin (mTOR) plays an essential part in cell growth and catabolism. The downstream molecules of its signaling pathway regulate protein translation and cell autophagy to affect ZIKV replication,and its upstream Akt kinase activity also plays crucial role in virus infection process. This paper reviews the mechanism between the mTOR signaling pathway and ZIKV infection and replication from three aspects: ZIKV structure and replication, mTOR complex structure and signaling pathway, and the regulation of mTOR signaling pathway on ZIKV replication.

Hand, foot and mouth disease (HFMD) is an acute infectious disease caused by enterovirus infection. It has strong infectivity and multiple transmission routes, and is a long-term epidemic in the world. In the past decade, the pathogen spectrum of HFMD has undergone great changes worldwide. The dominant pathogenic agents transfer from enterovirus A71 (EV-A71) and coxsackievirus A(CV-A)16 to other enteroviruses, among which CV-A6 has the most significant growth trend. Although the monovalent inactivated EV-A71 vaccine has effectively controlled the infection and decreased the number of severe cases caused by EV-A71, it offers no cross-protection against enteroviruses of different serotypes, thus can not fully meet the prevention and control requirements of HFMD. It is urgent to develop multivalent vaccines that can simultaneously protect against multiple epidemic enteroviruses. This paper reviews the pathogen spectrum changes and vaccine research of HFMD in home and abroad.

Monoclonal antibody drugs have become an important research direction in the biomedical field nowadays due to their high specificity, strong targeting ability, and slight adverse reactions. Epitopes are specific regions or binding sites of antigens recognized by antibodies, so its efficient identification is crucial for drug discovery and design. This article mainly introduces the research progress of antibody epitope identification techniques including X-ray crystallography, phage display technology, ELISA and other methods, and describes the relevant principles, characteristics and their applications.