University of Massachusetts Medical School Faculty Publications

UMMS Affiliation

Department of Medicine

Publication Date

2021-05-24

Document Type

Article Preprint

Disciplines

Amino Acids, Peptides, and Proteins | Immunology of Infectious Disease | Immunopathology | Immunotherapy | Infectious Disease | Virus Diseases | Viruses

Abstract

Antibodies are principal immune components elicited by vaccines to induce protection from microbial pathogens. In the Thai RV144 HIV-1 vaccine trial, vaccine efficacy was 31% and the sole primary correlate of reduced risk was shown to be vigorous antibody response targeting the V1V2 region of HIV-1 envelope. Antibodies against V3 also were inversely correlated with infection risk in subsets of vaccinees. Antibodies recognizing these regions, however, do not exhibit potent neutralizing activity. Therefore, we examined the antiviral potential of poorly neutralizing monoclonal antibodies (mAbs) against immunodominant V1V2 and V3 sites by passive administration of human mAbs to humanized mice engrafted with CD34+ hematopoietic stem cells, followed by mucosal challenge with an HIV-1 infectious molecular clone (IMC) expressing the envelope of a tier 2 resistant HIV-1 strain. Treatment with anti-V1V2 mAb 2158 or anti-V3 mAb 2219 did not prevent infection, but both reduced the virus burden, and V3 mAb 2219 displayed a superior potency compared to V1V2 mAb 2158. While these mAbs had no or weak neutralizing activity and elicited undetectable levels of antibody-dependent cellular cytotoxicity (ADCC), V3 mAb 2219 displayed a greater capacity to bind virus- and cell-associated HIV-1 envelope and to mediate antibody-dependent cellular phagocytosis (ADCP) and C1q complement binding as compared to V1V2 mAb 2158. Mutations in the Fc region of 2219 abolished these effector activities and abrogated virus control in humanized mice. These results demonstrate the importance of Fc functions other than ADCC for antibodies without potent neutralizing activity.

Keywords

Immunology, antibodies, HIV-1, vaccines, mutations

Rights and Permissions

The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license.

DOI of Published Version

10.1101/2021.05.24.445493

Source

bioRxiv 2021.05.24.445493; doi: https://doi.org/10.1101/2021.05.24.445493. Link to preprint on bioRxiv.

Comments

This article is a preprint. Preprints are preliminary reports of work that have not been certified by peer review.

Full author list omitted for brevity. For the full list of authors, see article.

Journal/Book/Conference Title

bioRxiv

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

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