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46 results on '"Upadhyay, Chitra"'

1. Heterologous Ad26/Ad5 adenovirus-vectored vaccines elicited SARS-CoV-2-specific antibody responses with potent Fc activities

Author

Klingler, Jéromine, primary, Kowdle, Shreyas, additional, Bandres, Juan C., additional, Emami-Gorizi, Rozita, additional, Alvarez, Raymond A., additional, Rao, Priyanka G., additional, Amanat, Fatima, additional, Gleason, Charles, additional, Kleiner, Giulio, additional, Simon, Viviana, additional, Edelstein, Alexis, additional, Perandones, Claudia, additional, Upadhyay, Chitra, additional, Lee, Benhur, additional, and Hioe, Catarina E., additional

Published
2024
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3. Corrigendum: Vaccination with immune complexes modulates the elicitation of functional antibodies against HIV-1

Author

Hioe, Catarina E., primary, Liu, Xiaomei, additional, Banin, Andrew N., additional, Heindel, Daniel W., additional, Klingler, Je´romine, additional, Rao, Priyanka G., additional, Luo, Christina C., additional, Jiang, Xunqing, additional, Pandey, Shilpi, additional, Ordonez, Tracy, additional, Barnette, Philip, additional, Totrov, Maxim, additional, Zhu, Jiang, additional, Na´das, Arthur, additional, Zolla-Pazner, Susan, additional, Upadhyay, Chitra, additional, Shen, Xiaoying, additional, Kong, Xiang-Peng, additional, and Hessell, Ann J., additional

Published
2023
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5. Vaccination with immune complexes modulates the elicitation of functional antibodies against HIV-1

Author

Hioe, Catarina E., primary, Liu, Xiaomei, additional, Banin, Andrew N., additional, Heindel, Daniel W., additional, Klingler, Jéromine, additional, Rao, Priyanka G., additional, Luo, Christina C., additional, Jiang, Xunqing, additional, Pandey, Shilpi, additional, Ordonez, Tracy, additional, Barnette, Philip, additional, Totrov, Maxim, additional, Zhu, Jiang, additional, Nádas, Arthur, additional, Zolla-Pazner, Susan, additional, Upadhyay, Chitra, additional, Shen, Xiaoying, additional, Kong, Xiang-Peng, additional, and Hessell, Ann J., additional

Published
2023
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9. Non-neutralizing antibodies targeting the immunogenic regions of HIV-1 envelope reduce mucosal infection and virus burden in humanized mice

Author

Hioe, Catarina E., primary, Li, Guangming, additional, Liu, Xiaomei, additional, Tsahouridis, Ourania, additional, He, Xiuting, additional, Funaki, Masaya, additional, Klingler, Jéromine, additional, Tang, Alex F., additional, Feyznezhad, Roya, additional, Heindel, Daniel W., additional, Wang, Xiao-Hong, additional, Spencer, David A., additional, Hu, Guangnan, additional, Satija, Namita, additional, Prévost, Jérémie, additional, Finzi, Andrés, additional, Hessell, Ann J., additional, Wang, Shixia, additional, Lu, Shan, additional, Chen, Benjamin K., additional, Zolla-Pazner, Susan, additional, Upadhyay, Chitra, additional, Alvarez, Raymond, additional, and Su, Lishan, additional

Published
2022
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10. Immune Profiles to Distinguish Hospitalized Versus Ambulatory COVID-19 Cases in Older Patients

Author

Klingler, Jéromine, primary, Lambert, Gregory S., additional, Bandres, Juan C., additional, Emami-Gorizi, Rozita, additional, Nádas, Arthur, additional, Oguntuyo, Kasopefoluwa Y., additional, Amanat, Fatima, additional, Team, PARIS Study, additional, Simon, Viviana, additional, Lee, Benhur, additional, Zoller-Pazner, Susan, additional, Upadhyay, Chitra, additional, and Hioe, Catarina, additional

Published
2022
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11. Detection of Antibody Responses Against SARS-CoV-2 in Plasma and Saliva From Vaccinated and Infected Individuals

Author

Klingler, Jéromine, primary, Lambert, Gregory S., additional, Itri, Vincenza, additional, Liu, Sean, additional, Bandres, Juan C., additional, Enyindah-Asonye, Gospel, additional, Liu, Xiaomei, additional, Simon, Viviana, additional, Gleason, Charles R., additional, Kleiner, Giulio, additional, Chiu, Hsin-Ping, additional, Hung, Chuan-Tien, additional, Kowdle, Shreyas, additional, Amanat, Fatima, additional, Lee, Benhur, additional, Zolla-Pazner, Susan, additional, Upadhyay, Chitra, additional, and Hioe, Catarina E., additional

Published
2021
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12. SARS-CoV-2 mRNA vaccines induce a greater array of spike-specific antibody isotypes with more potent complement binding capacity than natural infection

Author

Klingler, Jéromine, Lambert, Gregory S., Itri, Vincenza, Liu, Sean, Bandres, Juan C., Enyindah-Asonye, Gospel, Liu, Xiaomei, Oguntuyo, Kasopefoluwa Y., Amanat, Fatima, Lee, Benhur, Zolla-Pazner, Susan, Upadhyay, Chitra, and Hioe, Catarina E.

Subjects
Adult, Male, saliva, COVID-19 Vaccines, SARS-CoV-2, Vaccination, COVID-19, ADCP, neutralization, Middle Aged, Antibodies, Viral, Antibodies, Neutralizing, Article, antibody isotypes, Immunoglobulin G, Antibody Formation, Spike Glycoprotein, Coronavirus, Humans, Female, complement fixation, Aged
Abstract

Antibodies (Abs) are essential for the host immune response against SARS-CoV-2, and all the vaccines developed so far have been designed to induce Abs targeting the SARS-CoV-2 spike. Many studies have examined Ab responses in the blood from vaccinated and infected individuals. However, since SARS-CoV-2 is a respiratory virus, it is also critical to understand the mucosal Ab responses at the sites of initial virus exposure. Here, we examined plasma versus saliva Ab responses in vaccinated and convalescent patients. Although saliva levels were significantly lower, a strong correlation was observed between plasma and saliva total Ig levels against all SARS-CoV-2 antigens tested. Virus-specific IgG1 responses predominated in both saliva and plasma, while a lower prevalence of IgM and IgA1 Abs was observed in saliva. Antiviral activities of plasma Abs were also studied. Neutralization titers against the initial WA1 (D614G), B.1.1.7 (alpha) and B.1.617.2 (delta) strains were similar but lower against the B.1.351 (beta) strain. Spike-specific antibody-dependent cellular phagocytosis (ADCP) activities were also detected and the levels correlated with spike-binding Ig titers. Interestingly, while neutralization and ADCP potencies of vaccinated and convalescent groups were comparable, enhanced complement deposition to spike-specific Abs was noted in vaccinated versus convalescent groups and corresponded with higher levels of IgG1 plus IgG3 among the vaccinated individuals. Altogether, this study demonstrates the detection of Ab responses after vaccination or infection in plasma and saliva that correlate significantly, although Ig isotypic differences were noted. The induced plasma Abs displayed Fab-mediated and Fc-dependent functions with comparable neutralization and ADCP potencies, but a greater capacity to activate complement was elicited upon vaccination.

Published
2021

14. Non-neutralizing antibodies targeting the immunogenic regions of HIV-1 envelope reduce mucosal infection and virus burden in humanized mice

Author

Hioe, Catarina E., primary, Li, Guangming, additional, Liu, Xiaomei, additional, Tsahouridis, Ourania, additional, He, Xiuting, additional, Funaki, Masaya, additional, Klingler, Jéromine, additional, Tang, Alex F., additional, Feyznezhad, Roya, additional, Heindel, Daniel W., additional, Wang, Xiao-Hong, additional, Spencer, David A., additional, Hu, Guangna, additional, Satija, Namita, additional, Prévost, Jérémie, additional, Finzi, Andrés, additional, Hessell, Ann, additional, Wang, Shixia, additional, Lu, Shan, additional, Chen, Benjamin K., additional, Zolla-Pazner, Susan, additional, Upadhyay, Chitra, additional, Alvarez, Raymond, additional, and Su, Lishan, additional

Published
2021
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18. Signal peptide of HIV-1 envelope modulates glycosylation impacting exposure of V1V2 and other epitopes

Author

Upadhyay, Chitra, primary, Feyznezhad, Roya, additional, Cao, Liwei, additional, Chan, Kun-Wei, additional, Liu, Kevin, additional, Yang, Weiming, additional, Zhang, Hui, additional, Yolitz, Jason, additional, Arthos, James, additional, Nadas, Arthur, additional, Kong, Xiang-Peng, additional, Zolla-Pazner, Susan, additional, and Hioe, Catarina E., additional

Published
2020
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19. Signal Peptide of HIV-1 Envelope Modulates Glycosylation Impacting Exposure of V1V2 Epitopes

Author

Upadhyay, Chitra, primary, Feyznezhad, Roya, additional, Cao, Liwei, additional, Chan, Kun-Wei, additional, Liu, Kevin, additional, Yang, Weiming, additional, Zhang, Hui, additional, Yolitz, Jason, additional, Arthos, James, additional, Nadas, Arthur, additional, Kong, Xiang-Peng, additional, Zolla-Pazner, Susan, additional, and Hioe, Catarina E., additional

Published
2020
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21. P2X1 Selective Antagonists Block HIV-1 Infection through Inhibition of Envelope Conformation-Dependent Fusion

Author

Soare, Alexandra Y., primary, Malik, Hagerah S., additional, Durham, Natasha D., additional, Freeman, Tracey L., additional, Alvarez, Raymond, additional, Patel, Foramben, additional, Satija, Namita, additional, Upadhyay, Chitra, additional, Hioe, Catarina E., additional, Chen, Benjamin K., additional, and Swartz, Talia H., additional

Published
2020
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22. P2X1 selective antagonists block HIV-1 infection through inhibition of envelope conformation-dependent fusion

Author

Soare, Alexandra Y., primary, Malik, Hagerah S., additional, Durham, Natasha D., additional, Freeman, Tracey L., additional, Alvarez, Raymond, additional, Patel, Foramben, additional, Satija, Namita, additional, Upadhyay, Chitra, additional, Hioe, Catarina E., additional, Chen, Benjamin K., additional, and Swartz, Talia H., additional

Published
2019
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25. Detection of NP, N3 and N7 antibodies to avian influenza virus by indirect ELISA using yeast-expressed antigens

Author

Ammayappan Arun, Upadhyay Chitra, and Vakharia Vikram N

Subjects
Infectious and parasitic diseases, RC109-216
Abstract

Abstract Background Avian influenza viruses, belonging to the family Orthomyxoviridae, possess distinct combinations of hemagglutinin (H) and the neuraminidase (N) surface glycoproteins. Typing of both H and N antigens is essential for the epidemiological and surveillance studies. Therefore, it is important to find a rapid, sensitive, and specific method for their assay, and ELISA can be useful for this purpose, by using recombinant proteins. Results The nucleoprotein (NP) and truncated neuraminidase subtype 3 and 7 of avian influenza virus (AIV) were expressed in Saccharomyces cerevisiae and used to develop an indirect enzyme-linked immunosorbent assay for antibody detection. The developed assays were evaluated with a panel of 64 chicken serum samples. The performance of NP-ELISA was compared with the commercially available ProFlok® AIV ELISA kit. The results showed comparable agreement and sensitivity between the two tests, indicating that NP-ELISA assay can be used for screening the influenza type A antibody in AIV infected birds. The N3 and N7- ELISAs also reacted specifically to their type specific sera and did not exhibit any cross-reaction with heterologous neuraminidase subtype specific sera. Conclusion The study demonstrates the expression of the NP, N3, and N7 proteins of AIV in yeast (S. cerevisiae) and their application in developing an indirect ELISA for detecting NP, N3 and N7 antibodies from AIV-infected chicken sera. The described indirect ELISAs are rapid, sensitive, specific and can be used as promising tests during serological surveillance.

Published
2009
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26. Complete genomic sequence analysis of infectious bronchitis virus Ark DPI strain and its evolution by recombination

Author

Gelb Jack, Upadhyay Chitra, Ammayappan Arun, and Vakharia Vikram N

Subjects
Infectious and parasitic diseases, RC109-216
Abstract

Abstract An infectious bronchitis virus Arkansas DPI (Ark DPI) virulent strain was sequenced, analyzed and compared with many different IBV strains and coronaviruses. The genome of Ark DPI consists of 27,620 nucleotides, excluding poly (A) tail, and comprises ten open reading frames. Comparative sequence analysis of Ark DPI with other IBV strains shows striking similarity to the Conn, Gray, JMK, and Ark 99, which were circulating during that time period. Furthermore, comparison of the Ark genome with other coronaviruses demonstrates a close relationship to turkey coronavirus. Among non-structural genes, the 5'untranslated region (UTR), 3C-like proteinase (3CLpro) and the polymerase (RdRp) sequences are 100% identical to the Gray strain. Among structural genes, S1 has 97% identity with Ark 99; S2 has 100% identity with JMK and 96% to Conn; 3b 99%, and 3C to N is 100% identical to Conn strain. Possible recombination sites were found at the intergenic region of spike gene, 3'end of S1 and 3a gene. Independent recombination events may have occurred in the entire genome of Ark DPI, involving four different IBV strains, suggesting that genomic RNA recombination may occur in any part of the genome at number of sites. Hence, we speculate that the Ark DPI strain originated from the Conn strain, but diverged and evolved independently by point mutations and recombination between field strains.

Published
2008
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27. Modulation of Antibody Responses to the V1V2 and V3 Regions of HIV-1 Envelope by Immune Complex Vaccines

Author

Hioe, Catarina E., primary, Kumar, Rajnish, additional, Upadhyay, Chitra, additional, Jan, Muzafar, additional, Fox, Alisa, additional, Itri, Vincenza, additional, Peachman, Kristina K., additional, Rao, Mangala, additional, Liu, Lily, additional, Lo, Nathan C., additional, Tuen, Michael, additional, Jiang, Xunqing, additional, Kong, Xiang-Peng, additional, and Zolla-Pazner, Susan, additional

Published
2018
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32. Rationally Designed Vaccines Targeting the V2 Region of HIV-1 gp120 Induce a Focused, Cross-Clade-Reactive, Biologically Functional Antibody Response

Author

Zolla-Pazner, Susan, primary, Powell, Rebecca, additional, Yahyaei, Sara, additional, Williams, Constance, additional, Jiang, Xunqing, additional, Li, Wei, additional, Lu, Shan, additional, Wang, Shixia, additional, Upadhyay, Chitra, additional, Hioe, Catarina E., additional, Totrov, Max, additional, and Kong, Xiangpeng, additional

Published
2016
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33. Detection of NP, N3 and N7 antibodies to avian influenza virus by indirect ELISA using yeast-expressed antigens

Author

Upadhyay, Chitra, Upadhyay, Chitra, Ammayappan, Arun, Vakharia, Vikram N, Upadhyay, Chitra, Upadhyay, Chitra, Ammayappan, Arun, and Vakharia, Vikram N

Abstract

Avian influenza viruses, belonging to the family Orthomyxoviridae, possess distinct combinations of hemagglutinin (H) and the neuraminidase (N) surface glycoproteins. Typing of both H and N antigens is essential for the epidemiological and surveillance studies. Therefore, it is important to find a rapid, sensitive, and specific method for their assay, and ELISA can be useful for this purpose, by using recombinant proteins. The nucleoprotein (NP) and truncated neuraminidase subtype 3 and 7 of avian influenza virus (AIV) were expressed in Saccharomyces cerevisiae and used to develop an indirect enzyme-linked immunosorbent assay for antibody detection. The developed assays were evaluated with a panel of 64 chicken serum samples. The performance of NP-ELISA was compared with the commercially available ProFlok® AIV ELISA kit. The results showed comparable agreement and sensitivity between the two tests, indicating that NP-ELISA assay can be used for screening the influenza type A antibody in AIV infected birds. The N3 and N7- ELISAs also reacted specifically to their type specific sera and did not exhibit any cross-reaction with heterologous neuraminidase subtype specific sera. The study demonstrates the expression of the NP, N3, and N7 proteins of AIV in yeast (S. cerevisiae) and their application in developing an indirect ELISA for detecting NP, N3 and N7 antibodies from AIV-infected chicken sera. The described indirect ELISAs are rapid, sensitive, specific and can be used as promising tests during serological surveillance.

Published
2009

36. Functional and Structural Characterization of Human V3-Specific Monoclonal Antibody 2424 with Neutralizing Activity against HIV-1 JRFL

Author

Kumar, Rajnish, primary, Pan, Ruimin, additional, Upadhyay, Chitra, additional, Mayr, Luzia, additional, Cohen, Sandra, additional, Wang, Xiao-Hong, additional, Balasubramanian, Preetha, additional, Nádas, Arthur, additional, Seaman, Michael S., additional, Zolla-Pazner, Susan, additional, Gorny, Miroslaw K., additional, Kong, Xiang-Peng, additional, and Hioe, Catarina E., additional

Published
2015
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40. Complete genomic sequence analysis of infectious bronchitis virus Ark DPI strain and its evolution by recombination

Author

Ammayappan, Arun, Ammayappan, Arun, Upadhyay, Chitra, Gelb, Jack Jr., Vakharia, Vikram N, Ammayappan, Arun, Ammayappan, Arun, Upadhyay, Chitra, Gelb, Jack Jr., and Vakharia, Vikram N

Abstract

An infectious bronchitis virus Arkansas DPI (Ark DPI) virulent strain was sequenced, analyzed and compared with many different IBV strains and coronaviruses. The genome of Ark DPI consists of 27,620 nucleotides, excluding poly (A) tail, and comprises ten open reading frames. Comparative sequence analysis of Ark DPI with other IBV strains shows striking similarity to the Conn, Gray, JMK, and Ark 99, which were circulating during that time period. Furthermore, comparison of the Ark genome with other coronaviruses demonstrates a close relationship to turkey coronavirus. Among non-structural genes, the 5'untranslated region (UTR), 3C-like proteinase (3CL pro) and the polymerase (RdRp) sequences are 100% identical to the Gray strain. Among structural genes, S1 has 97% identity with Ark 99; S2 has 100% identity with JMK and 96% to Conn; 3b 99%, and 3C to N is 100% identical to Conn strain. Possible recombination sites were found at the intergenic region of spike gene, 3'end of S1 and 3a gene. Independent recombination events may have occurred in the entire genome of Ark DPI, involving four different IBV strains, suggesting that genomic RNA recombination may occur in any part of the genome at number of sites. Hence, we speculate that the Ark DPI strain originated from the Conn strain, but diverged and evolved independently by point mutations and recombination between field strains.

Published
2008

44. Signal peptide exchange alters HIV-1 envelope antigenicity and immunogenicity.

Author

Upadhyay C, Rao P, Behzadi MA, Feyznezhad R, Lambert GS, Kumar R, Kumar M, Yang W, Jiang X, Luo CC, Nadas A, Arthos J, Kong XP, Zhang H, Hioe CE, and Duty JA

Subjects
Animals, Mice, Humans, Antibodies, Monoclonal immunology, HIV Envelope Protein gp160 immunology, Antibodies, Neutralizing immunology, Glycosylation, Mice, Inbred BALB C, Female, HIV Infections immunology, HIV Infections prevention & control, HIV Infections virology, HIV-1 immunology, HIV Antibodies immunology, HIV Envelope Protein gp120 immunology, AIDS Vaccines immunology, Protein Sorting Signals
Abstract

Introduction: HIV-1 envelope (Env) is the key target for antibodies (Abs) against the virus and thus an important HIV-1 vaccine component. Env is synthesized from a gp160 precursor with a signal peptide (SP) at its N-terminus. This study investigated the influence of the SP on Env antigenicity and immunogenicity., Methods: Env proteins from two HIV-1 isolates, AA05 and AC02, were analyzed as gp120 and gp160 in their native wild-type (WT) forms and as chimeras with swapped SPs (AA05-02 and AC02-05). The WT and chimeric Env were assessed for antigenicity and glycosylation using monoclonal antibodies (mAbs) and glycan probes. Immunogenicity was tested in mice using three vaccine types: gp120 protein, gp120 DNA+gp120 protein, and gp120 DNA+gp160 DNA., Results: The recombinant AC02 gp120 protein was antigenically superior to AA05 as indicated by higher reactivity with most mAbs tested. When SPs were swapped, the antigenicity of the chimeric gp120s (AA05-02 and AC02-05) resembled that of the gp120s from which the SPs were derived; AA05-02 was similar to AC02 and vice versa. Glycan probe reactivity followed a similar pattern: AA05-02 and AC02 showed similar affinity to high-mannose specific mAbs and lectins. Interestingly, the antigenicity of gp160s showed an opposite pattern; membrane-bound gp160 expressed with the AA05 SP (AA05 and AC02-05) showed greater mAb binding than gp160 with the AC02 SP (AC02 and AA05-02). Mice immunized with gp120 protein showed that AA05-02 induced stronger cross-reactive binding Ab responses than AA05 WT, and AC02 elicited stronger responses than AC02-05, indicating AC02 SP enhanced gp120 immunogenicity. However, when DNA vaccines were included (gp120 DNA+gp120 protein and gp120 DNA+gp160 DNA), the use of heterologous SPs diminished the immunogenicity of the WT immunogens. Among the three vaccine regimens tested, only gp120 DNA+gp160 DNA immunization elicited low-level Tier 2 neutralizing Abs, with AA05 WT inducing Abs with greater neutralization capabilities than AA05-02., Conclusion: These data demonstrate that the SP can significantly impact the antigenicity and immunogenicity of HIV-1 Env proteins. Hence, while SP swapping is a common practice in constructing Env immunogens, this study highlights the importance of careful consideration of the effects of replacing native SPs on the immunogenicity of Env vaccines., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Upadhyay, Rao, Behzadi, Feyznezhad, Lambert, Kumar, Kumar, Yang, Jiang, Luo, Nadas, Arthos, Kong, Zhang, Hioe and Duty.)

Published
2024
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45. Broadly Neutralizing Antibody Epitopes on HIV-1 Particles are exposed after Virus Interaction with Host Cells.

Author

Rao PG, Lambert GS, and Upadhyay C

Abstract

The envelope glycoproteins (Env) on HIV-1 virions are the sole target of broadly neutralizing antibodies (bNAb) and the focus of vaccines. However, many cross-reactive conserved epitopes are often occluded on virus particles, contributing to the evasion of humoral immunity. This study aimed to identify the Env epitopes that are exposed/occluded on HIV-1 particles and to investigate the mechanisms contributing to their masking. Using a flow cytometry-based assay, three HIV-1 isolates, and a panel of antibodies, we show that only select epitopes including V2i, gp120-g41 interface, and gp41-MPER are accessible on HIV-1 particles, while V3, V2q, and select CD4bs epitopes are masked. These epitopes become accessible after allosteric conformational changes are induced by pre-binding of select Abs, prompting us to test if similar conformational changes are required for these Abs to exhibit their neutralization capability. We tested HIV-1 neutralization where virus-mAb mix was pre-incubated/not pre-incubated for one hour prior to adding the target cells. Similar levels of neutralization were observed under both assay conditions, suggesting that the interaction between virus and target cells sensitizes the virions for neutralization via bNAbs. We further show that lectin-glycan interactions can also expose these epitopes. However, this effect is dependent on the lectin specificity. Given that, bNAbs are the ideal for providing sterilizing immunity and are the goal of current HIV-1 vaccine efforts, these data offer insight on how HIV-1 may occlude these vulnerable epitopes from the host immune response. In addition, the findings can guide the formulation of effective antibody combinations for therapeutic use.

Published
2023
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46. Detection of Antibody Responses against SARS-CoV-2 in Plasma and Saliva from Vaccinated and Infected Individuals.

Author

Klingler J, Lambert GS, Itri V, Liu S, Bandres JC, Enyindah-Asonye G, Liu X, Simon V, Gleason CR, Kleiner G, Chiu HP, Hung CT, Kowdle S, Amanat F, Lee B, Zolla-Pazner S, Upadhyay C, and Hioe CE

Abstract

Antibodies (Abs) are essential for the host immune response against SARS-CoV-2, and all the vaccines developed so far have been designed to induce Abs targeting the SARS-CoV-2 spike. Many studies have examined Ab responses in the blood from vaccinated and infected individuals. However, since SARS-CoV-2 is a respiratory virus, it is also critical to understand the mucosal Ab responses at the sites of initial virus exposure. Here, we examined plasma versus saliva Ab responses in vaccinated and convalescent patients. Although saliva levels were significantly lower, a strong correlation was observed between plasma and saliva total Ig levels against all SARS-CoV-2 antigens tested. Virus-specific IgG1 responses predominated in both saliva and plasma, while a lower prevalence of IgM and IgA1 Abs was observed in saliva. Antiviral activities of plasma Abs were also studied. Neutralization titers against the initial WA1 (D614G), B.1.1.7 (alpha) and B.1.617.2 (delta) strains were similar but lower against the B.1.351 (beta) strain. Spike-specific antibody-dependent cellular phagocytosis (ADCP) activities were also detected and the levels correlated with spike-binding Ig titers. Interestingly, while neutralization and ADCP potencies of vaccinated and convalescent groups were comparable, enhanced complement deposition to spike-specific Abs was noted in vaccinated versus convalescent groups and corresponded with higher levels of IgG1 plus IgG3 among the vaccinated individuals. Altogether, this study demonstrates the detection of Ab responses after vaccination or infection in plasma and saliva that correlate significantly, although Ig isotypic differences were noted. The induced plasma Abs displayed Fab-mediated and Fc-dependent functions with comparable neutralization and ADCP potencies, but a greater capacity to activate complement was elicited upon vaccination., Competing Interests: Conflict of interest The Icahn School of Medicine at Mount Sinai has filed patent applications relating to SARS-CoV-2 serological assays and listed Dr. Viviana Simon as co-inventor. Mount Sinai has spun out a company, Kantaro, to market serological tests for SARS-CoV-2. The other authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Published
2021
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