A trimeric RBD protein as a booster vaccine enhanced the humoral response and broad neutralization against SARS-CoV-2 in mice / 中华微生物学和免疫学杂志

Objective:To investigate the efficacy of a SARS-CoV-2 recombinant protein vaccine as a booster dose.Methods:A new immunogen, namely RBD-sc-trimer, was designed by tandem repeating of single receptor binding domain (RBD) of SARS-CoV-2 spike (S) protein to mimic the trimeric form of RBD presented by the virus. The RBD-sc-trimer protein was expressed as a His-tagged fusion protein using a baculovirus expression system and purified by nickel affinity column. The purified protein was identified by Western blot. Its in vitro binding activity to human angiotensin converting enzyme 2 (hACE2) was analyzed by ELISA. The immunogenicity of RBD-sc-trimer as well as RBD proteins of other forms including RBD dimer (RBD-Fc), RBD monomer (RBD) and S protein trimer (S trimer) as a booster dose was evaluated in BALB/c mice. Results:In terms of both binding and neutralizing antibodies against SARS-CoV-2, RBD-sc-trimer showed an immunogenicity that was superior to that of RBD-Fc and RBD and close to the level of S trimer. The antibody response induced by RBD-sc-trimer was characterized as Th1-biased. Moreover, it displayed a stronger cross-neutralization activity against SARS-CoV-2 Beta, Delta and Omicron variants. The titer of neutralizing antibody against Omicron induced by RBD-sc-trimer only decreased by 9.1 folds relative to the prototype strain, while the antibody response induced by RBD-Fc and S trimer decreased by 68.4 and 70.8 folds, respectively.Conclusions:The recombinant protein, RBD-sc-trimer, which was capable of eliciting stronger humoral response in mice as a booster dose and showed the superiority in raising cross-reactive antibodies against SARS-CoV-2 variants over non-trimeric RBD forms, should be considered as an optimal immunogen for the development of more effective SARS-CoV-2 vaccines.

Expert recommendations on booster immunization strategies of 2019-nCoV vaccines / 中华临床感染病杂志

Since the end of 2019, the COVID-19 caused by 2019-nCoV has emerged and the pandemic ravaged the world, which seriously threatens global public health security and economic development. 2019-nCoV vaccine is an effective weapon to combat the viral infection, however, studies have shown that vaccine-induced immune protection decreases over time, coupled with some novel and immune escape variants continual emerging. Therefore, it is urgent to complete booster immunization to improve protection. At present, 2019-nCoV vaccines based on a variety of technical platforms have been approved and available in China. Therefore, we developed this sequential vaccination strategy guide to provide documentation guidance for the prevention and control of the epidemic caused by 2019-nCoV and its variant strains.

Progress in the mechanism of glycometabolism in memory CD8+ T cell formation / 中华微生物学和免疫学杂志

CD8+T cells are critical immune cells protecting the body against infection and cancer. Long-lived memory CD8+T cells formed in a prior infection can reproduce to mount a faster and stronger im-mune response at a second encounter with the cognate antigen. The activation, clonal expansion and re-sponse of T cells are energetically demanding processes tightly coupled in cellular metabolism. Meanwhile, changes in cellular metabolism could also affect the development of memory T cells following acute infection. In this review, we discussed the current understanding of the mechanism by which glycometabolic pathways manipulate the differentiation of memory CD8+T cells in order to provide reference for improving vaccine de-velopment and cancer treatment.

Erratum to: Irreversible phenotypic perturbation and functional impairment of B cells during HIV-1 infection / 医学前沿

The original version of this article unfortunately contained a mistake. One of the authors of this article has been misspelled. Xiaoyang Zhang should be Xiaoyan Zhang. The update is also provided here.

Clinical value of the plasma circular RNA hsa_circ_0009024 in the diagnosis and treatment of pulmonary tuberculosis / 中华检验医学杂志

Objective Detecting plasma level of circular RNA(circRNA)hsa_circ_0009024 in pulmonary tuberculosis(TB)patients,and evaluating its diagnostic value for TB.Methods From January 2016 to December 2016, a hosptial-based, case-control study was performed, which include 90 untreated active pulmonary tuberculosis patients(TB group),75 healthy people(healthy control)and 84 patient with other diseases(other disease group).Plasma level of circRNA hsa_circ_0009024 was detected by real-time quantitative polymerase chain reaction.Furthermore, the 90 patients with TB were divided into different subgroups according to cavity formation and the lung fields involvement: patients without lung cavity(55 cases)vs those with lung cavity(35 cases),patients with involvement of <2 lung fields(49 cases)vs≥2 lung fields(41 cases).Plasma levels of hsa _circ_0009024 of 41 TB patientswere monitored andcomparedbefore and after 3 months anti-TB therapy.The sensitivity and specificity of plasma hsa_circ_0009024 were analyzed by using the receiver operating characteristic(ROC)curve.The comparison between two groups was performed with Mann-Whitney U test and the comparison among multigroupswas conducted with Kruskal-Wallis H test.Results Plasma levels of hsa_circ_0009024 in TB patients[1.98(1.42, 2.71)]were significantly higher than healthy controls[1.03(0.78,1.33)]and other disease groups[1. 13(0.77,1.51)](H=76.58,P<0.0001).Plasma levels of hsa_circ_0009024 in cavity pulmonary TB patients were higher than pulmonary TB patients without cavity(U=392.50,P<0.0001).Plasma levels of hsa_circ_0009024 in TB patients with involvement of ≥2 lung fields were higher than <2 lung fields(U=590.50,P=0.0008).As compared to pre -treatment[2.01(1.41, 2.71)], the plasma hsa_circ_0009024 levels decreased significantly in 3 months[1.22(0.85,1.47)](U=292.50,P<0.0001)after anti-TB therapy.The area under the receiver operating characteristics curve(AUC)of plasma hsa_circ_0009024 in discriminating the patients with TB from normal controls, pneumonia patients and lung cancer patients were 0.841 and 0.811, respectively.Conclusion The hsa_circ_0009024 can be used as a potential biomarker in TB diagnosis and monitoring.

Research progress in broad neutralizing antibodies and universal vaccines against influenza A virus / 中华微生物学和免疫学杂志

Influenza vaccination is the most effective means to prevent and control influenza epi-demics, and the universal influenza vaccine which can induce broad and long-term protective effect is still in its infancy. Up to date, several broad neutralizing antibodies that can antagonize a variety of influenza A vi-ruses have been identified, and the crystal structure of the antibody and HA complex reveals at least three highly conserved epitopes. Deep insights into the molecular mechanism of the interactions between neutrali-zing antibodies and virus antigen can elicit a new strategy not only for rational design of universal influenza vaccines, but also for the development of antibody-based therapeutics against influenza virus. In this paper, advances in research of universal neutralizing antibodies and vaccines for Influenza A virus are reviewed.

Differential expression profile of long non-coding RNA in the lipopolysaecharide-induced inflammation of monocyte-derived macrophages / 中华危重病急救医学

Objective To analyze the expression profile of long non-coding RNA (lncRNA) in the lipopolysaecharide (LPS)-induced inflammation of monocyte-derived macrophages.Methods Peripheral blood mononuclear cells were derived from healthy donor and induced into macrophages. The macrophages were divided into blank control group and LPS (1 mg/L) stimulated 12 hours group. Culture supernatants and cell pellets were harvested in each group, enzyme linked immunosorbent assay (ELISA) was used to assay the production changes of interleukins (IL-1β and IL-6), and tumor necrosis factor-α (TNF-α) in the supernatant. The technique of lncRNA microarray was used to test the lncRNA expression profile in LPS-induced inflammation of macrophages and control macrophages. The raw data of lncRNA were pretreated for normalization. Five lncRNA expressions were validated by real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Furthermore, qRT-PCR was used to detect the expression of NR_028034 in macrophages after LPS-induced inflammation.Results ① The contents of IL-1β (ng/L:562.93±61.17 vs. 59.74±15.68), IL-6 (ng/L: 702.46±92.31 vs. 71.66±18.25) and TNF-α (ng/L: 794.50±63.89 vs. 85.12±22.07) in the LPS group were significantly higher than those in the blank control group (allP < 0.01). These results indicated that the inflammatory model of human macrophages was constructed successfully. ② Compared with blank control group, and 1479 lncRNA which have more than 2 folds variation and significant difference (P < 0.05) by statistical analysis was defined as lncRNA with differential expression. Among these lncRNA, LPS group showed 953 up- regulated and 526 down- regulated genes by 2 folds and 49 up- regulated and 35 down- regulated genes by 5 folds. ③ qRT-PCR results were generally consistent with the microarray data. ④ The expression of NR_028034 was increased by (4.41±0.65), (11.56±2.04), (18.58±1.36) folds compared with blank control group at 3, 6, 12 hours after LPS stimulation (allP < 0.01).Conclusions These data show a significantly altered lncRNA expression profile in the LPS-induced inflammation of monocyte-derived macrophages, suggesting that lncRNA may be involved in regulation of macrophages inflammatory response.

Diagnosis and Treatment Significance of Invasive and Noninvasive Operation for Ventilator-associated Pneumonia / 沈阳医学院学报

Objective:To investigate the diagnosis and treatment significance of invasive and noninvasive operation for ventilator?as?sociated pneumonia ( VAP ) . Methods:A total of 80 cases of VAP suspected patients who had received mechanical ventilation at least 48 hours in ICU from Jun 2014 to Mar 2015 were enrolled. Patients were randomly divided into four groups including noninvasive operation group ( F) , invasive operation group ( Q) , mix group 1 ( H1) and mix group 2 ( H2) . VAP diagnosis rate between groups as well as living time, antibiotic use time, survival rate, calcitonin levels and APACHE II score, oxygenation index were analyzed. Results:Specimen from invasive operation had higher specimens to cultivate positive rate than that from noninvasive operation ( P<0?05), but there was no statistic significant difference in VAP diagnosis rate between two methods (P>0?05). Conclusion:Noninva?sive operation collecting samples for VAP diagnosis is also accurate as invasive one. Collecting specimens from sputum suction tube in the clinical treatment on airway suction is a low cost and simple noninvasive operation.

Research Progress in Escape Mutations of the Human Immunodeficiency Virus under Pressure of HLA-Restricted Cytotoxic T Lymphocytes / 病毒学报

Human immunodeficiency virus type 1 (HIV-1)-specific cytotoxic T lymphocytes (CTLs) play a critical role in the control of HIV-1 infection and replication. HIV-1 evades CTL mediated pressure through viral escape mutations within targeted CTLs epitopes or flanking regions, but this process is usually associated with a viral fitness cost. The mutated epitopes may weaken the level of the original CTL responses, however, the immune system holds potential to mount denovo responses towards those newly emerged epitopes. This article briefly summarizes recent research progress regarding the competition between HIV-1's escape mutations and host CTL responses.

HIV/AIDS related mortality in southern Shanxi province and its risk factors / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore factors influencing mortality rate of HIV/AIDS and to improve the effectiveness of antiretroviral therapy (ART).</p><p><b>METHODS</b>By means of retrospective cohort study and the AIDS control information system, HIV/AIDS case reports and antiviral treatment information of 4 cities in southern Shanxi province up to end of December 2012 were selected, to calculate the mortality rate and treatment coverage based on further data collected, along with analysis using the Cox proportional hazards survival regression.</p><p><b>RESULTS</b>4 040 cases confirmed of HIV/AIDS were included in this study. The average age was (36.0 ± 12.9) years, with 65.3% being male, 56.5% being married, 73.5% having junior high school education or lower, 58.4% being peasants, 54.3% with sexually transmitted infection (40.1% were heterosexual, 14.2% were homosexual), and 38.9% were infected via blood transmission (20.2% were former plasma donors, 16.2% blood transfusion or products recipients, 2.4% were injection drug users). Overall mortality decreased from 40.2 per 100 person/year in 2004 to 6.3 per 100 person/year in 2012, with treatment coverage concomitantly increasing from almost 14.8% to 63.4%. Cox proportional hazards survival regression was used on 4 040 qualified cases, demonstrating the top mortality risk factor was without antiretroviral therapy (RR = 14.9, 95% CI: 12.7-17.4). Cox proportional hazards survival regression was made on 1 938 cases of antiviral treatment, demonstrating that the mortality risk of underweight or obese before treatment was higher than those of normal and overweight cases (RR = 2.7, 95% CI: 1.6-4.5), and the mortality of those having a CD4(+) T-lymphocyte count ≤ 50 cells per µl before treatment was more than 50 cases (RR = 2.6, 95% CI: 1.5-4.5); Cox proportional hazards survival regression was made on 2 102 cases of untreated cases, demonstrating the mortality risk of those initially diagnosed as AIDS was higher than those initially diagnosed as HIV (RR = 3.4, 95% CI: 2.9-4.0).</p><p><b>CONCLUSION</b>The ART could successfully make lower HIV/AIDS mortality rate, indicating effective ART can further decrease mortality.</p>

Escaping mechanism from innate immunity mediated clearance by high pathogenic influenza virus during infection / 中国免疫学杂志

Severe influenza infection is usually associated with hypercytokinemia ,but the type Ⅰ Interferon remains at low lever or absence.The regulatory mechanism on or the immune escaping mechanism from type I interferon by virus remains to be deter -mined.We briefly summarized the progress in this field and raise several questions to be addressed in the future .

Epigenetic regulatory effects of the methylation of CpG island shore on the expression of lag3 gene in various human T cell lines / 中华微生物学和免疫学杂志

Objective To investigate the effects of DNA methylation on the expression of lympho-cyte activation gene 3 (lag3) in different human T cell lines.Methods A quantitative PCR and a flow cy-tometry analysis were performed to measure the expression of lag3 gene in various T cell lines at mRNA and protein levels.The distribution of CpG sites within the promoter and body of lag3 gene was detected to locate the potential regulatory region(s) (CpG island and CpG island shore).The levels of DNA methylation in each cell line were analyzed.The T cell lines were demethylated with 5-Aza-2′-deoxycytidine (5-Aza-2′-dc) for further investigation on the changes of lag3 gene expression and DNA methylation.Results Jurkat E6-1 cells showed the highest expression level of lag3 gene as compared with J.CaM1.6 and CEM cells.Hyperm-ethylated CpG islands were detected in cells of each cell line.The methylation levels of CpG island shore in J.CaM1.6 and CEM cells were higher than that in Jurkat E6-1 cells.Treatment of J.CaM1.6 and CEM cells with 5-Aza-2′-dc significantly promoted the expression of lag3 gene at mRNA and protein levels as well as the demethylation of CpG island shore.No significant differences with the expression of lag3 gene and the methylation of CpG island were observed in Jurkat E6-1 cells with or without 5-Aza-2′-dc stimulation.Con-clusion Methylation and demethylation of CpG island shore played important roles in regulating the tran-scription of lag3 gene.

In vitro anti-HIV activity and its possible mechanism of an extract of herb medicines, SanJiangDan / 中华微生物学和免疫学杂志

Objective To study in vitro anti-HIV activity of an extract of herb medicines,SanJiangDan,and the possible mechanism.Methods The main active ingredient of SanJiangDan was extracted by distillation.Three subtypes of HIV pseudovirus (B subtype,C subtype,CRF01_AE subtype) were used to evaluate the anti-HIV activity of SanJiangDan extract in vitro.The possible mechanism was evaluated through analyzing the effects of SanJiangDan extract on the expression of surface receptors and cytokines by T cells.The cytotoxicity of SanJiangDan extract was detected by using four different sources of cell lines including epithelial cells Caco-2 cells,TZM cells,Huh7 cells derived from liver cells and lymphocyte Jurkat-T cells.Results SanJiangDan extract effectively inhibited the infection of HIV pseudoviruses at concentrations of 1.6 mg/ml and 0.16 mg/ml.The inhibition rates were 30.9％,36.6％ and 65.0％ for B subtype,C subtype and CRF01_AE subtype respectively at the concentration of 0.16 mg/ml.As the concentration increased to 1.6 mg/ml,the inhibition rates increased to 96.4％ (B subtype),97.4％ (C subtype) and 99.5％ (CRF01_AE subtypes),but no toxicity to host cells was detected.Moreover,SanJiangDan extract inhibited the expression of HIV surface receptors including CD4,CXCR4 and CCR5 on TZM-bl cells,but enhanced IL-2 production.Conclusion SanJiangDan extract could inhibit HIV pseudovirus infection without causing cytotoxicity to host cells in vitro.The possible mechanism might be associated with the reduced expression of CD4,CXCR4 and CCR5 and enhanced secretion of IL-2 as well.

Epitope competition weakens specific T cell response to subdominant epitopes / 中华微生物学和免疫学杂志

Objective To elucidate the influences of epitope competition on the frequency and average intensity of specific T cell response.Methods C57BL/6 mice were immunized with either single epitope DNA vaccines (pSV-gag92 or pSV-env203) or fusion gene DNA vaccine (pSV-gag/env).Gag92and Env203 epitope-specific CD8 T cell responses were analyzed by intracellular cytokine staining assay.Results Gag92-specific IFN-γ+CD8 T cells that were induced by pSV-gag92 accounted for 0.415 00％ ±0.045 88％ of the total CD8 T cells,which was much more than that induced by pSV-gag/env of 0.058 67％ + 0.019 64％.Moreover,the mean fluorescence intensity of Gag92-specific TNF-α-IFN-γ+CD8 T cells (296.70+14.08) elicited by pSV-gag/env was significantly lower than that of Env203-specific TNF-α-IFN-γ+CD8 T cells (818.00+49.34).Conclusion Epitope competition could significantly decrease both the frequency and the average intensity of specific T cell response to subdominant epitopes.

The impact of procedural sequence on the quality of bowel preparation in patients with propofol sedation for same-day bidirectional endoscopy / 中华消化内镜杂志

Objective To evaluate the impact of sequence on the quality of bowel preparation in patients with anesthesia for same-day sequential bidirectional endoscopy and propose the optimal procedural sequence.Methods Single center blinded randomized observational study.Sixty-five patients were randomized to either the gastroscopy-first group or the colonoscopy-first group.Bowel cleanliness according to Boston bowel preparation scale (BBPS) scores were evaluated,also done the propofol dosage,caecal intubation time,procedure duration and complications.Results The BBPS score of entire colon showed no difference (6.72 ± 1.34 vs.6.89 ± 1.50,P =0.638),but the BBPS of ileal-cecum portion was higher in the colonoscopy-first group (1.21 ±0.54 vs.1.55 ±0.73,P =0.035).The total procedure time,propofol dosage and complications were similar between the two groups.Conclusion The bowel cleanliness of ileal-cecum portion in colonoscopy-first group is better than that of gastroscopy-first group during sequential bidirectional endoscopy in patients with propofol sedation.We propose colonoscopy first in patients with suspicious ileal-cecum lesion.

The prevalence and dynamics of human immunodeficiency virus-1 subtypes among men who have sex with men in Beijing / 中华传染病杂志

Objective To investigate the subtype distribution and changing trend of human immunodeficiency virus (HIV)-1 strains among men who have sex with men (MSM) during 2005-2011 in Beijing.Methods Five serial cross-sectional surveys of MSM were conducted in the year of 2005-2006,2007,2008,2009,and 2010-2011 in Chaoyang district of Beijing.Whole blood samples were collected and then RNA was extracted.HIV-1 gag gene was characterized by reverse transcriptase and nested polymerase chain reaction (RT-PCR) amplification,DNA sequencing,and phylogenetic analysis of viral sequences to determine the HIV-1 subtypes.Results Phylogenetic analysis of the sequences revealed that the predominant subtypes of HIV-1 gag gene included subtype B,CRF01_AE and CRF07_BC.And CRF15_01B was detected from the year of 2008.In addition,significant changes of the distributions of subtypes and CRFs occurred from 2005 to 2011 in HIV+ MSM.Subtype B showed a significant decreased trend,while the proportions of CRF01 _AE and CRF07_BC significantly increased in the 7-year period,particularly that of CRF01_AE.Conclusions The substantial changes are observed in the diversity of HIV-1 strains circulating among MSM in Beijing during a 7-year period.

Immunogenicity of DNA vaccines encoding regulatory/accessory proteins derived from three different prevalent strains in China / 中华微生物学和免疫学杂志

0bjective To determine the immunogenicities of DNA vaccines expressing tat-rev-integrase(c-half)-vif-neffusion genes(TRIVN) derived from prevalent B', B'/C and AE recombinant subtypes of HIV-1 in China. Methods Two DNA vaccines were constructed by inserting the codon optimized tat-revintegrase(c-half)-vif-nef fusion genes derived from B' and B'/C subtype of HIV-1 into mammalian expression vector pSVI. 0. DNA vaccine containing tat-rev-integrase (c-half)-vif-nef fusion gene derived from HIV-1AE2f has been constructed previously. In vitro expression efficiencies of three DNA vaccines were determined by Western blot and their immunogenicities were compared by immunizing female BALB/c mice. IFN-γ ELISPOT assay was used to read out the specific T cell immunity. Results The constructed DNA vaccines were validated by restriction enzyme digestion and DNA sequencing. Western blot assay showed three constructed DNA vaccines could be expressed at a comparable level in vitro. After vaccination, AE-TRIVN mounted T cell immune responses at (948.0 ± 330.0) SFCs/106 splenocytes, followed by the mixed DNA vaccine[ (500.0 ± 155.0) SFCs/106 splenocytes ], RL-TRIVN r[ ( 195. 1 ± 44.0) SFCs/106 splenocytes ]and CN-TRIVN [ (89.5 ± 17.0) SFCs/106 splenocytes]. Interestingly, we observed that single DNA vaccination induced specific T cell responses predominantly targeting Integrase (C-half) and Vif, whereas the mixed DNA could significantly improve T cell responses against Nef. Conclusion AE-TRIVN was the most immunogenic among the three DNA vaccines and the mixed DNA vaccination could change the immunogenic hierarchy of T cell epitopes across the fusion genes vaccine.

Cross-genome HIV-specific cytotoxic T-lymphocyte responses among HIV-1 infected individuals with varied infection time and routes / 中华检验医学杂志

Objective To investigate and compare the features of the HIV-1-specific CTL responses among three HIV-infected groups with varied infection history. Methods Three HIV-infeeted groups were enrolled in this study, including two groups infected by blood transmission (one group has been infected for more than 10 years and the other for 1-2 years) and one group of the man who have sex with man. The HIV-1-specific CTL responses were quantified by an IFN-γ based ELISPot assay with a peptide matrix system containing overlapping peptides spanning the entire HIV-1 Clade B genomic consensus sequences. Results The responding rate of CTL responses against all 17 peptide pools among the group that infected 1-2 years,the group infected more than 10 years and the group of MSM were 40% ,65% ,23%. One way ANOVO analysis showed that the responding rate of CTL responses against all 17 peptide pools were statistical significant among the three groups (F=19.96, P＜0.01);the magnitude of CTL responses of the three groups were 0-5 835 SFCs/106 PBMC, 0-7 225 SFCs/106PBMC, 0-9 740SFCs/106pBMC, Kruskal-Wallis test showed that the magnitude of CTL responses were statistical significant among the three groups( H = 101.90 , P ＜0.01);the breadth of CTL were 7 ( 2-11 ), 11(9-14) and 4 (2-6) respectively and Kruskal- Wallis test showed that the breadth of CTL had no statistical significant among the three groups( H = 34. 75 ,P ＜0. 01 ). The sequence of responding rate, magnitude and breadth of CTL from high to low was the group that had been infected for more than 10 years, the group infected 1-2 years and the sex transmission group. The common characteristics of the CTL response among the three groups were that the responding rate and the magnitude of the peptide Nef and Gag was higher than other peptide's. The magnitude of CTL responses among three different CD4count groups (CD4 ＜ 200/μl, CD4 200-500/μl, CD4 ≥500/μl,) was 0-18 475 SFCs/106pBMC, 350-34 095 SFCs/106pBMC, 490-21 550 SFCs/106 PBMC and had no statistic difference among the three different CD4 groups(H=2.93, P=0.23) while the breadth of CTL was 3(0-8), 10(2-17), 10 (1-17)respoctively and the breadth of CTL was lower in the group of CD4 count less than 200/μl than the other two groups( H = 14. 72, P ＜ 0. 01 ). The magnitude of CTL responses among three different viral load (VL)groups (VL＜ LDL, LDL ＜ VL ＜ 1 × 104 copys/ml, VL≥1 ×104 copys/ml) was 490-18 475 SFCs/106pBMC, 0-24 115 SFCs/106pBMC, 770-34 095 SFCs/106 pBMC and had no statistic difference among the three different viral load groups ( H = 0.79, P=0.67) and the breadth of the three different viral load groups CTL was 8( 1-17), 11 (0-17), 8 (1-16) and Kruskal-Wallis test showed that there was no statistic difference among the three different viral load groups (H =5.27, P =0. 07). Conclusions All groups predominantly develope T cell immune responses against Nef and Gag proteins. With the elapse of HIV infection, the CTL responses are increased in both magnitude and responding rate. This information is important for vaccine development.

Research advance and clinical application of ELISpot assay / 中华检验医学杂志

ELISpot assay has been widely used in basic and clinical research with its unique advantages. ELISpot is highly efficient in epitope screening, quantification of the epitope specific T cells, determining the TCR affinity and evaluating vaccine efficacy. In addition, ELISpot has been increasingly employed in diagnosis, differentiating diagnosis, evaluating patients' immune state, treatment efficacy, and evaluation of the prognosis. Overall, with the further improvement of this assay, ELISpot will play a critical role in the development of human health.

Immunogenicity of DNA vaccines encoding structural proteins and regulatory/accessory proteins derived from an HIV-1 CRF01_AE isolate circulating in China / 中华微生物学和免疫学杂志

Objective To construct two DNA vaccines encoding Gag-Env fusion protein and Tat-Rev-Integrase(C-half)-Vif-Nef fusion protein derived from the first HIV-1 CRF01_AE isolate(AE2f) in Chi-na and to evaluate the immunogenicity in mice. Methods Two DNA vaccines were constructed by inserting the codon optimized and synthesized gag-env fusion gene and tat-rev-integrase(c-half)-vif-nef fusion gene de-rived from AE2f into mammalian expression vector pDRVISV1. 0, the generated DNA vaccines were desig-nated as pSVAE/GE and pSVAE/TRIVN, respectively, and their in vitro expression were determined by Western blot with transfected 293T cells. Mice were i. m. immunized with either pDRVI1.0 as mock control, pSVAE/GE or pSYAE/TRIVN for 4 times at two-week interval. Two weeks following the final im-munization, cellular responses to pool of HIV-1 Env, Gag, Tat, Rev, Intergrase, Vif and Nef peptides were evaluated by ELISPOT assay. Results The construction of DNA vaccine pSVAE/GE and pSVAE/TRIVN was validated by restriction enzyme digestion and bidirectional sequencing. Western blot showed a specific band at molecular mass 220×10~3 in lane of pSVAE/GE transfeeted 293T cell and a specific band at 95×10~3 in the lane of pSVAE/TRIVN. Both DNA vaccines mounted significant specific T cell responses with (3010 ± 566) SFC/10~6 splenocytes for DNA vaccine pSV AE/GE and (948 ± 737) SFC/10~6 spleno-cytes for DNA vaccine pSVAE/TRIVN, whereas the mock control of pDRVISV1.0 only raised marginal T cell responses. Conclusion Both pSVAE/GE and pSVAE/TRIVN were capable of expressing the inserted fusion immunogen genes and able to elicit vigorous cellular immune responses, therefore, these DNA vac-cines are highly immunogenic.