BACKGROUND The role of diverse antibodies in mediating peripheral nerve injury in Guillain-Barrésyndrome(GBS)is becoming clearer,but positivity for multiple antibodies in one case is uncommon.To our knowledge,thi...BACKGROUND The role of diverse antibodies in mediating peripheral nerve injury in Guillain-Barrésyndrome(GBS)is becoming clearer,but positivity for multiple antibodies in one case is uncommon.To our knowledge,this is the first case involving GBS with positive anti-sulfatide,anti-GT1a,and anti-GT1b antibodies.CASE SUMMARY A 20-year-old female patient was admitted to the hospital due to weakness of limbs for 5 d,and deterioration of the weakness and muscle aches for 1 d.The patient's limbs were weak,but the tendon reflexes in the part of the limbs were normal.There was no comorbid peripheral nociception or deep sensory dysfunction.She was diagnosed with GBS and was discharged after receiving intravenous human immunoglobulin pulse therapy.CONCLUSION In this article,the clinical manifestations,neurophysiological examination,and auxiliary examination findings of a GBS patient positive for multiple antibodies were analyzed to improve the identification of the disease by clinical physicians at an early stage.展开更多
BACKGROUND Miller fisher syndrome(MFS)is a variant of Guillain-Barrésyndrome,an acute immune-mediated peripheral neuropathy that is often secondary to viral infections.Anti-ganglioside antibodies play crucial rol...BACKGROUND Miller fisher syndrome(MFS)is a variant of Guillain-Barrésyndrome,an acute immune-mediated peripheral neuropathy that is often secondary to viral infections.Anti-ganglioside antibodies play crucial roles in the development of MFS.The positive rate of ganglioside antibodies is exceptionally high in MFS patients,particularly for anti-GQ1b antibodies.However,the presence of other ganglioside antibodies does not exclude MFS.CASE SUMMARY We present a 56-year-old female patient who suddenly developed right blepharoptosis and progressively worsening vision in both eyes.There were flu symptoms prior to onset,and a coronavirus disease 2019 test was positive.On physical examination,the patient exhibited bilateral extraocular muscle paralysis,weakened reflexes in both limbs,and impaired coordination.The cerebrospinal fluid examination results showed no obvious abnormalities.Bilateral peroneal nerve F-waves were not extracted.Serum anti-GD1b IgG and anti-GT1a IgG antibodies were positive.The patient received intravenous methylprednisolone(1000 mg/day),with the dosage gradually decreased.Additionally,intravenous high-dose immunoglobulin treatment was administered for 5 days(0.4 g/kg/day)from day 2 to day 6 of hospitalization.The patient’s symptoms improved after treatment with immunoglobulins and hormones.CONCLUSION Positive ganglioside antibodies may be used as supporting evidence for the diagnosis;however,the diagnosis of MFS is more reliant on clinical symptoms.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
Some unique subclasses of Camelidae antibodies are devoid of the light chain, and the antigen binding site is comprised exclusively of the variable domain of the heavy chain （VHH）. The recombinant VHHs have a high p...Some unique subclasses of Camelidae antibodies are devoid of the light chain, and the antigen binding site is comprised exclusively of the variable domain of the heavy chain （VHH）. The recombinant VHHs have a high potential as alternative reagents for the next generation of immunoassay. In particular, they might be very useful for molecular mimicry. The present study demonstrated an alpaca immunized with the F（ab＇）z fragment of anti-aflatoxin B1 mAb and developed an important anti-idiotypic （anti-ld） responses. Antigen-specific elution method was used for panning private anti-ld VHHs from the constructed alpaca VHH library. The selected VHHs were expressed, renatured, purified, and then identified by a competitive enzyme-linked immunosorbent assay （ELISA）. Our findings indicated that the VHH would be an alternative tool for haptens mimicry studies.展开更多
Objective： In order to evaluate potential application for diagnosis and prognosis of non-small cell-lung cancer （NSCLC）, as well as to determine its role in the pathogenesis of the disease, we prepared anti-human h...Objective： In order to evaluate potential application for diagnosis and prognosis of non-small cell-lung cancer （NSCLC）, as well as to determine its role in the pathogenesis of the disease, we prepared anti-human hnRNPA2/B1 potyclonal antibody. Methods： Prokaryotic expression vector of pET28a （＋）-hnRNP A2/B1 was constructed and bansformed into E.coli BL21. The recombinant protein induced by IPTG was purified and injected to rabbits for antibody preparation. Expression of hnRN P A2/B1 was examined in 45 tissues of NSCLC and 16 inflammatory pseudotumor tissues of lung by immunohistochemistry with the antibody. The commercial hnRNP A2/B1 monoclonal antibody was used as a controI.Results： （1） Polyclonal an-tibody against hnRNP A2/B1 with high title was obtained. （2） The positive staining in NSCLC tissues was 62.22%, which was substantially higher than that in normal tissues （40%, P = 0.035） or inflammatory pseudotumor tissues （31.25%, P=0.033）. （3） Expression of hnRNP A2/B1 positively correlated with age and the history of smoking, whereas it negatively correlated with differentiation staging of tumors. （4） Follow-up study showed that the survival time of patients with positive staining was significantly shorter than that of patients without hnRNP A2/B1 expression （P=0.048）. Conclusion： It is successful to make the recombinant protein and prepare the polyclonal antibody agonist human hnRNP A2/B1. It may be a valuable marker for the diagnosis and prognosis of NSCLC. Our results provide a basis for further study in clinical application.展开更多
BACKGROUND: A single-chain antibody ( ScFv) phage display library was created by cloning antigen-binding re- gions of VH (variable domain) and VL gene repertoires as fusion proteins with a minor coat protein of filame...BACKGROUND: A single-chain antibody ( ScFv) phage display library was created by cloning antigen-binding re- gions of VH (variable domain) and VL gene repertoires as fusion proteins with a minor coat protein of filamentous phage, from which high affinity completely humanized ScFv against PreS1 of hepatitis B virus could be screened and characterized. METHODS: A combinatorial library of phage-display hu- man ScFv genes, which were derived from peripheral blood lymphocytes immunized by peptide PreS1 in vitro, was constructed. The library contained 7 × 108 clones. RESULTS: After 3 rounds panning, a high affinity (K = 10-7-10-8 mol/L) ScFv specific to PreS1 was obtained. Sequence analysis showed that the VH belonged to the VH4 family and Vλ to Vλ4. CONCLUSIONS: The described ScFv may provide a more satisfactory therapy. This application further illustrates that the method of in vitro antigen stimulation is expeditious for the source of human immune antibody library.展开更多
In this study, we have used a direct immunoassay where the simple binding between antigen and an antibody is detected. Immunoassays were performed in a drop system, monitoring the frequency decrease of the quartz-crys...In this study, we have used a direct immunoassay where the simple binding between antigen and an antibody is detected. Immunoassays were performed in a drop system, monitoring the frequency decrease of the quartz-crystal microbalance device because of mass increasing during immunoreaction. The QCM sensor was coated on both sides by gold electrodes, only one side of the crystal (liquid side) was in contact with the solution;the other side (contact side) was always dry. We tested a piezoelectric immunosensor for aflatoxin B1 (AFLA-B1) mycotoxin detection through the immo- bilization of DSP-anti-AFLAB1 antibody (AFLA-B1-Ab anti AFLAB1) on gold-coated quartz crystals (AT-cut/5 MHz). The DSP (3,3’-Dithiodipropionic-acid-di-N-hydroxysuccinimide ester) was used for the covalent attachment of the proteins. The piezoelectric crystal electrodes were pretreated by DSP for 15 min, rinsed with water and dried in a gentle flow of nitrogen gas. Then the DSP-coated crystals were installed in a sample holder and exposed to the anti-AFLAB1 antibody and to the AFLA-BI. Frequency and resistance shifts (Δf and ΔR) were measured simultaneously. Δf versus AFLA-BI concentrations in the range of 0.5 - 10 ppb exhibited a perfect linear correlation with a coefficient of above 0.998.展开更多
基金The Scientific and Technological Innovation Talent Team Project of Zunyi City,No.[2022]2Guizhou Maotai Hospital Research and Talent Cultivation Funding Project,No.MTYK 2022-06.
文摘BACKGROUND The role of diverse antibodies in mediating peripheral nerve injury in Guillain-Barrésyndrome(GBS)is becoming clearer,but positivity for multiple antibodies in one case is uncommon.To our knowledge,this is the first case involving GBS with positive anti-sulfatide,anti-GT1a,and anti-GT1b antibodies.CASE SUMMARY A 20-year-old female patient was admitted to the hospital due to weakness of limbs for 5 d,and deterioration of the weakness and muscle aches for 1 d.The patient's limbs were weak,but the tendon reflexes in the part of the limbs were normal.There was no comorbid peripheral nociception or deep sensory dysfunction.She was diagnosed with GBS and was discharged after receiving intravenous human immunoglobulin pulse therapy.CONCLUSION In this article,the clinical manifestations,neurophysiological examination,and auxiliary examination findings of a GBS patient positive for multiple antibodies were analyzed to improve the identification of the disease by clinical physicians at an early stage.
文摘BACKGROUND Miller fisher syndrome(MFS)is a variant of Guillain-Barrésyndrome,an acute immune-mediated peripheral neuropathy that is often secondary to viral infections.Anti-ganglioside antibodies play crucial roles in the development of MFS.The positive rate of ganglioside antibodies is exceptionally high in MFS patients,particularly for anti-GQ1b antibodies.However,the presence of other ganglioside antibodies does not exclude MFS.CASE SUMMARY We present a 56-year-old female patient who suddenly developed right blepharoptosis and progressively worsening vision in both eyes.There were flu symptoms prior to onset,and a coronavirus disease 2019 test was positive.On physical examination,the patient exhibited bilateral extraocular muscle paralysis,weakened reflexes in both limbs,and impaired coordination.The cerebrospinal fluid examination results showed no obvious abnormalities.Bilateral peroneal nerve F-waves were not extracted.Serum anti-GD1b IgG and anti-GT1a IgG antibodies were positive.The patient received intravenous methylprednisolone(1000 mg/day),with the dosage gradually decreased.Additionally,intravenous high-dose immunoglobulin treatment was administered for 5 days(0.4 g/kg/day)from day 2 to day 6 of hospitalization.The patient’s symptoms improved after treatment with immunoglobulins and hormones.CONCLUSION Positive ganglioside antibodies may be used as supporting evidence for the diagnosis;however,the diagnosis of MFS is more reliant on clinical symptoms.
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supported by a grant from the National Basic Research Program of China(2013CB127804)the National Natural Science Funds(31171696,China)the Research Program of the State Key Laboratory of Food Science and Technology,Nanchang University(SKLF-MB-201002)
文摘Some unique subclasses of Camelidae antibodies are devoid of the light chain, and the antigen binding site is comprised exclusively of the variable domain of the heavy chain （VHH）. The recombinant VHHs have a high potential as alternative reagents for the next generation of immunoassay. In particular, they might be very useful for molecular mimicry. The present study demonstrated an alpaca immunized with the F（ab＇）z fragment of anti-aflatoxin B1 mAb and developed an important anti-idiotypic （anti-ld） responses. Antigen-specific elution method was used for panning private anti-ld VHHs from the constructed alpaca VHH library. The selected VHHs were expressed, renatured, purified, and then identified by a competitive enzyme-linked immunosorbent assay （ELISA）. Our findings indicated that the VHH would be an alternative tool for haptens mimicry studies.
基金a grant from the Provincial Natural Sciences Foundation of Anhui(No.050430703)Major Scientific Research Programs of the Department of Science and Technology of Anhui(No.05023086)
文摘Objective： In order to evaluate potential application for diagnosis and prognosis of non-small cell-lung cancer （NSCLC）, as well as to determine its role in the pathogenesis of the disease, we prepared anti-human hnRNPA2/B1 potyclonal antibody. Methods： Prokaryotic expression vector of pET28a （＋）-hnRNP A2/B1 was constructed and bansformed into E.coli BL21. The recombinant protein induced by IPTG was purified and injected to rabbits for antibody preparation. Expression of hnRN P A2/B1 was examined in 45 tissues of NSCLC and 16 inflammatory pseudotumor tissues of lung by immunohistochemistry with the antibody. The commercial hnRNP A2/B1 monoclonal antibody was used as a controI.Results： （1） Polyclonal an-tibody against hnRNP A2/B1 with high title was obtained. （2） The positive staining in NSCLC tissues was 62.22%, which was substantially higher than that in normal tissues （40%, P = 0.035） or inflammatory pseudotumor tissues （31.25%, P=0.033）. （3） Expression of hnRNP A2/B1 positively correlated with age and the history of smoking, whereas it negatively correlated with differentiation staging of tumors. （4） Follow-up study showed that the survival time of patients with positive staining was significantly shorter than that of patients without hnRNP A2/B1 expression （P=0.048）. Conclusion： It is successful to make the recombinant protein and prepare the polyclonal antibody agonist human hnRNP A2/B1. It may be a valuable marker for the diagnosis and prognosis of NSCLC. Our results provide a basis for further study in clinical application.
文摘BACKGROUND: A single-chain antibody ( ScFv) phage display library was created by cloning antigen-binding re- gions of VH (variable domain) and VL gene repertoires as fusion proteins with a minor coat protein of filamentous phage, from which high affinity completely humanized ScFv against PreS1 of hepatitis B virus could be screened and characterized. METHODS: A combinatorial library of phage-display hu- man ScFv genes, which were derived from peripheral blood lymphocytes immunized by peptide PreS1 in vitro, was constructed. The library contained 7 × 108 clones. RESULTS: After 3 rounds panning, a high affinity (K = 10-7-10-8 mol/L) ScFv specific to PreS1 was obtained. Sequence analysis showed that the VH belonged to the VH4 family and Vλ to Vλ4. CONCLUSIONS: The described ScFv may provide a more satisfactory therapy. This application further illustrates that the method of in vitro antigen stimulation is expeditious for the source of human immune antibody library.
文摘In this study, we have used a direct immunoassay where the simple binding between antigen and an antibody is detected. Immunoassays were performed in a drop system, monitoring the frequency decrease of the quartz-crystal microbalance device because of mass increasing during immunoreaction. The QCM sensor was coated on both sides by gold electrodes, only one side of the crystal (liquid side) was in contact with the solution;the other side (contact side) was always dry. We tested a piezoelectric immunosensor for aflatoxin B1 (AFLA-B1) mycotoxin detection through the immo- bilization of DSP-anti-AFLAB1 antibody (AFLA-B1-Ab anti AFLAB1) on gold-coated quartz crystals (AT-cut/5 MHz). The DSP (3,3’-Dithiodipropionic-acid-di-N-hydroxysuccinimide ester) was used for the covalent attachment of the proteins. The piezoelectric crystal electrodes were pretreated by DSP for 15 min, rinsed with water and dried in a gentle flow of nitrogen gas. Then the DSP-coated crystals were installed in a sample holder and exposed to the anti-AFLAB1 antibody and to the AFLA-BI. Frequency and resistance shifts (Δf and ΔR) were measured simultaneously. Δf versus AFLA-BI concentrations in the range of 0.5 - 10 ppb exhibited a perfect linear correlation with a coefficient of above 0.998.
