This observational prospective study was conducted on 25 patients who had received a full 3-dose COVID-19 vaccination scheme with a follow-up ranging from 12 to 19 months after the last injection. The aim of the study...This observational prospective study was conducted on 25 patients who had received a full 3-dose COVID-19 vaccination scheme with a follow-up ranging from 12 to 19 months after the last injection. The aim of the study was focused on a single biological indicator the anti-spike IgG antibody titer. The age of the patients ranged from 51 to 85 years old. 15 out 25 patients (60%) presented a comorbidity. Our data showed a persistent positive anti-spike IgG antibodies titer ranging from 105 to 5680 BAU/mL (mean: 2661 BAU/mL) in all patients. In view of these results, systematic administration of a SARS-CoV-2 vaccine booster is questionable and should be individually tailored according to the patient medical condition and the anti-spike IgG antibody level.展开更多
Objective Pertussis cases have increased markedly since 2018 in Guangxi.The aim of this study was to evaluate antibody levels and the infection status of pertussis in the resident population.Method A total of 10,215 s...Objective Pertussis cases have increased markedly since 2018 in Guangxi.The aim of this study was to evaluate antibody levels and the infection status of pertussis in the resident population.Method A total of 10,215 serum samples from residents were collected from August-November 2018 and tested for anti-pertussis IgG and toxin IgG using the enzyme-linked immunosorbent assay(ELISA).Results Of the collected samples,1,833(17.94%)tested positive for anti-pertussis IgG,with the median concentration of 16.06 IU/mL.Antibody level<10 IU/mL accounted for more than 60%in children under 4 years of age,but declined with age,whereas the percentages of the other three levels(10-40,40-50,and≥50 IU/mL)increased almost with age(P<0.001).Moreover,7,924 samples were selected for anti-pertussis toxin IgG,of which 653(8.24%)tested positive(≥40 IU/mL)with the median concentration of 5.89 IU/mL,and 204 participants(2.56%)had recent pertussis infection(≥100 IU/mL).Among the different age groups,the highest rates of positivity and recent infection were observed at 11-20 years of age,the lowest positivity rate at 5 years of age,and the lowest recent infection rate at 4 years of age(P<0.001,P=0.005,respectively).Conclusion The survey results showed that all age groups in Guangxi lacked immunity against pertussis,which was one of the main factors contributing to the resurgence of pertussis in 2018.In addition,the prevalence of pertussis is relatively high in Guangxi,and its incidence is seriously underestimated,especially in adolescents and adults.展开更多
The CD4 binding site(CD4bs) of envelope glycoprotein(Env) is an important conserved target for anti-human immunodeficiency virus type 1(HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12(b12) ...The CD4 binding site(CD4bs) of envelope glycoprotein(Env) is an important conserved target for anti-human immunodeficiency virus type 1(HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12(b12) could recognize conformational epitopes that overlap the CD4 bs of Env. Different virus strains, even derived from the same individual, showed distinct neutralization susceptibility to b12. We examined the key amino acid residues affecting b12 neutralization susceptibility using single genome amplification and pseudovirus neutralization assay. Eleven amino acid residues were identified that affect the sensitivity of Env to b12. Through site-directed mutagenesis, an amino acid substitution at position 182 in the V2 region of Env was confirmed to play a key role in regulating the b12 neutralization susceptibility. The introduction of V182 L to a resistant strain enhanced its sensitivity to b12 more than twofold. Correspondingly, the introduction of L182 V to a sensitive strain reduced its sensitivity to b12 more than tenfold. Amino acid substitution at positions 267 and 346 could both enhance the sensitivity to b12 more than twofold. However, no additive effect was observed when the three site mutageneses were introduced into the same strain, and the sensitivity was equivalent to the single V182 L mutation. CRF07_BC is a major circulating recombinant form of HIV-1 prevalent in China. Our data may provide important information for understanding the molecular mechanism regulating the neutralization susceptibility of CRF07_BC viruses to b12 and may be helpful for a vaccine design targeting the CD4 bs epitopes.展开更多
Objective:Although immunity to malaria is reduced in pregnancy,the maternal immune system still continues to respond to malaria infection by the production of antibodies.IgG has been reported to play significant role ...Objective:Although immunity to malaria is reduced in pregnancy,the maternal immune system still continues to respond to malaria infection by the production of antibodies.IgG has been reported to play significant role in immune response against P.falciparum.Anti-MSP-1_(19) antibody and reactive oxygen species have been shown to be protective against malaria infection in children.This work assessed the response of anti-MSP-1_(19) antibody(a promising blood stage vaccine candidate antigen) and oxidative stress in 250 pregnant women.Methods: Blood samples were collected in dry and wet seasons.Plasmodium falciparum infection was determined by microscopy, anti-MSP-1_(19) IgG level was investigated using ELISA.Malondiadelhyde(MDA) and reduced glutathione (GSH) were used as indicators of oxidative stress and they were quantified spectrophotometrically.Results: Parasitaemia was significantly higher(P<0.05) in wet than dry season and its level decreased with gravidity.There was a significant increase(P<0.05) in anti-MSP-1_(19) IgG and MDA levels in the dry than wet season.Anti-MSP-1_(19) IgG and MDA levels were significantly higher in P.falciparum positive primigravidae than P.falciparum negative primigravidae in both wet and dry seasons.In wet season anti-MSP-1_(19) IgG level was significantly increased(P<0.05) in P.falciparum positive multigravidae than P.falciparum negative. The anti-MSP-1_(19) IgG and MDA were significant higher in P.falciparum positive multigravidae than primigravidae. Reduced glutathione(GSH) level was significantly reduced(P<0.05) among malaria positive than malaria negative patients in both seasons.Conclusion:This study suggests that IgG and MDA response were positively associated with the presence of malaria infection.展开更多
文摘This observational prospective study was conducted on 25 patients who had received a full 3-dose COVID-19 vaccination scheme with a follow-up ranging from 12 to 19 months after the last injection. The aim of the study was focused on a single biological indicator the anti-spike IgG antibody titer. The age of the patients ranged from 51 to 85 years old. 15 out 25 patients (60%) presented a comorbidity. Our data showed a persistent positive anti-spike IgG antibodies titer ranging from 105 to 5680 BAU/mL (mean: 2661 BAU/mL) in all patients. In view of these results, systematic administration of a SARS-CoV-2 vaccine booster is questionable and should be individually tailored according to the patient medical condition and the anti-spike IgG antibody level.
基金approved by the Ethics Committee of the Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention(GXIRB 2018-0005),and the participants signed informed consent forms.
文摘Objective Pertussis cases have increased markedly since 2018 in Guangxi.The aim of this study was to evaluate antibody levels and the infection status of pertussis in the resident population.Method A total of 10,215 serum samples from residents were collected from August-November 2018 and tested for anti-pertussis IgG and toxin IgG using the enzyme-linked immunosorbent assay(ELISA).Results Of the collected samples,1,833(17.94%)tested positive for anti-pertussis IgG,with the median concentration of 16.06 IU/mL.Antibody level<10 IU/mL accounted for more than 60%in children under 4 years of age,but declined with age,whereas the percentages of the other three levels(10-40,40-50,and≥50 IU/mL)increased almost with age(P<0.001).Moreover,7,924 samples were selected for anti-pertussis toxin IgG,of which 653(8.24%)tested positive(≥40 IU/mL)with the median concentration of 5.89 IU/mL,and 204 participants(2.56%)had recent pertussis infection(≥100 IU/mL).Among the different age groups,the highest rates of positivity and recent infection were observed at 11-20 years of age,the lowest positivity rate at 5 years of age,and the lowest recent infection rate at 4 years of age(P<0.001,P=0.005,respectively).Conclusion The survey results showed that all age groups in Guangxi lacked immunity against pertussis,which was one of the main factors contributing to the resurgence of pertussis in 2018.In addition,the prevalence of pertussis is relatively high in Guangxi,and its incidence is seriously underestimated,especially in adolescents and adults.
基金supported by grants from National Science and Technology Major Project(2012ZX10004701)
文摘The CD4 binding site(CD4bs) of envelope glycoprotein(Env) is an important conserved target for anti-human immunodeficiency virus type 1(HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12(b12) could recognize conformational epitopes that overlap the CD4 bs of Env. Different virus strains, even derived from the same individual, showed distinct neutralization susceptibility to b12. We examined the key amino acid residues affecting b12 neutralization susceptibility using single genome amplification and pseudovirus neutralization assay. Eleven amino acid residues were identified that affect the sensitivity of Env to b12. Through site-directed mutagenesis, an amino acid substitution at position 182 in the V2 region of Env was confirmed to play a key role in regulating the b12 neutralization susceptibility. The introduction of V182 L to a resistant strain enhanced its sensitivity to b12 more than twofold. Correspondingly, the introduction of L182 V to a sensitive strain reduced its sensitivity to b12 more than tenfold. Amino acid substitution at positions 267 and 346 could both enhance the sensitivity to b12 more than twofold. However, no additive effect was observed when the three site mutageneses were introduced into the same strain, and the sensitivity was equivalent to the single V182 L mutation. CRF07_BC is a major circulating recombinant form of HIV-1 prevalent in China. Our data may provide important information for understanding the molecular mechanism regulating the neutralization susceptibility of CRF07_BC viruses to b12 and may be helpful for a vaccine design targeting the CD4 bs epitopes.
基金partially supported by University of Ibadan senate research grant awarded to Dr OG Ademowo of Institute for Advanced Medical Re- search and Training,Universily of Ibadan,Ibadan, Nigeria
文摘Objective:Although immunity to malaria is reduced in pregnancy,the maternal immune system still continues to respond to malaria infection by the production of antibodies.IgG has been reported to play significant role in immune response against P.falciparum.Anti-MSP-1_(19) antibody and reactive oxygen species have been shown to be protective against malaria infection in children.This work assessed the response of anti-MSP-1_(19) antibody(a promising blood stage vaccine candidate antigen) and oxidative stress in 250 pregnant women.Methods: Blood samples were collected in dry and wet seasons.Plasmodium falciparum infection was determined by microscopy, anti-MSP-1_(19) IgG level was investigated using ELISA.Malondiadelhyde(MDA) and reduced glutathione (GSH) were used as indicators of oxidative stress and they were quantified spectrophotometrically.Results: Parasitaemia was significantly higher(P<0.05) in wet than dry season and its level decreased with gravidity.There was a significant increase(P<0.05) in anti-MSP-1_(19) IgG and MDA levels in the dry than wet season.Anti-MSP-1_(19) IgG and MDA levels were significantly higher in P.falciparum positive primigravidae than P.falciparum negative primigravidae in both wet and dry seasons.In wet season anti-MSP-1_(19) IgG level was significantly increased(P<0.05) in P.falciparum positive multigravidae than P.falciparum negative. The anti-MSP-1_(19) IgG and MDA were significant higher in P.falciparum positive multigravidae than primigravidae. Reduced glutathione(GSH) level was significantly reduced(P<0.05) among malaria positive than malaria negative patients in both seasons.Conclusion:This study suggests that IgG and MDA response were positively associated with the presence of malaria infection.
