Analysis of unsuccessful tests and the effect of prolonged clinical sample preprocessing in the GeneXpert MTB/RIF assay.

Background: The GeneXpert MTB/RIF (Xpert) assay is a widely used technology for detecting Mycobacterium tuberculosis (MTB) in clinical samples. However, the study on the failure of the Xpert assay during routine implementation and its potential solutions is limited.

Methods: We retrospectively analyzed the records of unsuccessful tests in the Xpert and the GeneXpert MTB/RIF Ultra (Ultra) assays between April 2017 and April 2021 at the Shanghai Public Health Clinical Center.

Responses to multiple injections with alum alone compared to injections with alum adsorbed to proteins in mice.

New effects and mechanisms of alum on innate immunity have emerged in recent years. A number of cellular and molecular mechanisms induced by aluminum adjuvant have been reported, while the role of NALP3 and inflammasome in the cellular pathway induced by alum is still controversial. The effect of injection of alum alone without vaccine antigen into human has not been reported so far.

[Immunogenicities and comparison of DNA vaccines encoding pol genes derived from B`/C and A/E recombinant HIV-1 strains].

Objective: To construct and compare the immunogenicities of DNA vaccines expressing pol genes derived from B`/C and A/E recombinant subtypes of HIV-1 in China.

Methods: Two DNA vaccines were constructed by inserting the codon optimized pol genes derived from B'/C and A/E subtypes of HIV-1 into mammalian expression vector pSV1.0.

Establishing a Th17 based mouse model for preclinical assessment of the toxicity of candidate microbicides.

Background: To effectively block the invasion of human immunodeficiency virus (HIV)-1 on mucosal surface, vaginal anti-HIV-1 microbicides should avoid inflammatory responses and disruption of mucosa integrity because these will facilitate transepithelial viral penetration and replication. However, existing models fail to predict and evaluate vaginal mucosal toxicity induced by microbicides, and most importantly, they are unable to identify subtle or subclinical inflammatory reactions. This study was designed to develop a cost-effective in vivo model to evaluate microbicide safety in a preclinical study which can recapitulate the mucosal topical reaction.

Chloramphenicol improved expression of recombinant cholera toxin B subunit in Escherichia coli and its adjuvanticity.

Background: Cholera toxin B subunit (CTB) was shown to be a potent adjuvant for protein immunogen, especially when inoculated through mucosal route. We aimed to optimize the expression approach for CTB and thereafter to determine the adjuvant effect on DNA vaccine.

Methods: Wild type CTB coding gene was amplified and cloned into prokaryotic expression vector pET-30a, and the recombinant CTB was expressed in the presence of different concentration of chloramphenicol and isopropyl β-D-thiogalactoside.

HIV-specific IL-2(+) and/or IFN-γ(+) CD8(+) T cell responses during chronic HIV-1 infection in former blood donors.

Objective: Conflicting data have been generated from previous studies to determine which kind of relationship exists between HIV-1 specific CD8 Tcell responses and HIV-1 viral load or CD4 count over the course of infection. In this study, 153 HIV-1 infected LTNPs were enrolled to investigate the role of HIV-1 specific CD8 T-cell responses in chronic HIV-1 infection among HIV-1 infected former blood donors.

Methods: The patients were stratified into three groups according to CD4 count: CD4≥500 cells/μL; 350 cells/μL≤CD4<500 cells/μL; CD4<350 cells/μL.

[Intranasal priming with HIV DNA vaccine and systemic boosting with recombinant vaccinia induce vigorous immune responses: experiment with mice].

Objective: To explore the strategy to raise both mucosal and systemic anti-HIV-1 immunity.

Methods: Eighteen BALB/c rats were randomly divided into 2 groups, experimental group and control group. The experimental group were further subdivided into 4 subgroups of 3 mice: 3-dose HIV DNA vaccine group, 3-dose DNA vaccine + cholera toxin (CT) adjuvant subgroup, 1-dose recombinant Tiantan strain vaccinia-based vaccine subgroup, and 3-dose DNA vaccine + CT adjuvant + Tiantan strain vaccinia-based vaccine subgroup.

[Capacity of HIV enzyme immunoassay diagnostic kits to detect antibodies against different genotypes of HIV].

Objective: To investigate the capacity of commercial HIV enzyme immunoassay (EIA) diagnostic kits to detect antibodies against different genotypes of HIV.

Methods: HIV RNA was detected with RT-PCR from samples positive for HIV antibody. The purified PCR products were sequenced directly and the genotypes of HIV from samples were analyzed.