Isolation and characterization of a protective monoclonal antibody targeting outer membrane protein (OmpA) against tuberculosis

ABSTRACT Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) complex is an important zoonotic infectious disease around the world, and the One Health approach is an essential strategy for TB prevention and control. The abundant surface antigens present on the cell wall of Mtb can induce pro...

Full description

Saved in:
Bibliographic Details
Main Authors: Huoming Li, Jiahong Ji, Mengjin Qu, Xiuling Ma, You Zuo, Minghui Tang, Lingyuan Zeng, Hao Li
Format: Article
Language:English
Published: American Society for Microbiology 2025-04-01
Series:Microbiology Spectrum
Subjects:
Online Access:https://journals.asm.org/doi/10.1128/spectrum.02942-24
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849337710513225728
author Huoming Li
Jiahong Ji
Mengjin Qu
Xiuling Ma
You Zuo
Minghui Tang
Lingyuan Zeng
Hao Li
author_facet Huoming Li
Jiahong Ji
Mengjin Qu
Xiuling Ma
You Zuo
Minghui Tang
Lingyuan Zeng
Hao Li
author_sort Huoming Li
collection DOAJ
description ABSTRACT Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) complex is an important zoonotic infectious disease around the world, and the One Health approach is an essential strategy for TB prevention and control. The abundant surface antigens present on the cell wall of Mtb can induce protective antibodies; however, its full characterization remains incomplete. Previous research has shown that antibodies targeting surface proteins can enhance host defense mechanisms. Therefore, identifying antigens that stimulate the production of protective antibodies is essential. In this study, we focused on a select antigen, outer membrane protein (OmpA), located on the outer membrane of Mtb. By screening for antibodies with protective effects in phagocytosis and intracellular killing in vitro, we identified a protective antibody targeting OmpA. We prepared an antibody, designated as 1E1, belonging to the IgG2b isotype, which exhibited high titers of 1:2,048,000. Further research demonstrated that antibody-induced protection was achieved by promoting opsonophagocytosis in a dose-dependent manner, enhancing phagosome-lysosome fusion, and inhibiting mycobacterial intracellular growth. These findings were corroborated in vivo, with a reduction in bacterial loads of approximately 0.7 log observed in the preventive group and almost 1.0 log in the therapeutic group of mice treated with the antibodies, compared to the negative control group. Cytotoxicity assays, animal toxicity analyses, and pharmacokinetic evaluations confirmed the safety and sustained effectiveness of the antibody in vivo. These findings indicate that OmpA can elicit protective antibodies and may serve as a treatment strategy for drug-resistant TB and a promising antigen for TB vaccine development.IMPORTANCEIn this study, we identified a protective antibody targeting the outer membrane protein (OmpA) of Mycobacterium tuberculosis. This monoclonal antibody (MAb) belongs to the IgG2b isotype and exhibits high titers of 1:2,048,000 to the antigen. The cell infection assays demonstrated that antibody protection was achieved by promoting opsonophagocytosis in a dose-dependent manner, enhancing phagosome-lysosome fusion, and inhibiting mycobacterial intracellular growth in vitro and ex vivo. Cytotoxicity assays, animal toxicity analyses, and pharmacokinetic evaluations confirmed the safety and sustained effectiveness of the antibody in vivo. Furthermore, the mAb 1E1 can reduce the organs' bacterial burdens and pathological damages in the prevention mouse model as well as the treatment models. Above all, in this study, we found a novel mAb named 1E1 with IgG2b isotype targeting OmpA can have protection against tuberculosis (TB) in mice, which may serve as a treatment strategy for drug-resistant TB and a promising antigen for TB vaccine development.
format Article
id doaj-art-1405e22ed76f4ea98ff4add461c4a66b
institution Kabale University
issn 2165-0497
language English
publishDate 2025-04-01
publisher American Society for Microbiology
record_format Article
series Microbiology Spectrum
spelling doaj-art-1405e22ed76f4ea98ff4add461c4a66b2025-08-20T03:44:36ZengAmerican Society for MicrobiologyMicrobiology Spectrum2165-04972025-04-0113410.1128/spectrum.02942-24Isolation and characterization of a protective monoclonal antibody targeting outer membrane protein (OmpA) against tuberculosisHuoming Li0Jiahong Ji1Mengjin Qu2Xiuling Ma3You Zuo4Minghui Tang5Lingyuan Zeng6Hao Li7National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, ChinaNational Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, ChinaKey Laboratory of Veterinary Public Health of Ministry of Agriculture, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, ChinaNational Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, ChinaNational Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, ChinaNational Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, ChinaNational Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, ChinaNational Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing, ChinaABSTRACT Tuberculosis (TB) caused by Mycobacterium tuberculosis (Mtb) complex is an important zoonotic infectious disease around the world, and the One Health approach is an essential strategy for TB prevention and control. The abundant surface antigens present on the cell wall of Mtb can induce protective antibodies; however, its full characterization remains incomplete. Previous research has shown that antibodies targeting surface proteins can enhance host defense mechanisms. Therefore, identifying antigens that stimulate the production of protective antibodies is essential. In this study, we focused on a select antigen, outer membrane protein (OmpA), located on the outer membrane of Mtb. By screening for antibodies with protective effects in phagocytosis and intracellular killing in vitro, we identified a protective antibody targeting OmpA. We prepared an antibody, designated as 1E1, belonging to the IgG2b isotype, which exhibited high titers of 1:2,048,000. Further research demonstrated that antibody-induced protection was achieved by promoting opsonophagocytosis in a dose-dependent manner, enhancing phagosome-lysosome fusion, and inhibiting mycobacterial intracellular growth. These findings were corroborated in vivo, with a reduction in bacterial loads of approximately 0.7 log observed in the preventive group and almost 1.0 log in the therapeutic group of mice treated with the antibodies, compared to the negative control group. Cytotoxicity assays, animal toxicity analyses, and pharmacokinetic evaluations confirmed the safety and sustained effectiveness of the antibody in vivo. These findings indicate that OmpA can elicit protective antibodies and may serve as a treatment strategy for drug-resistant TB and a promising antigen for TB vaccine development.IMPORTANCEIn this study, we identified a protective antibody targeting the outer membrane protein (OmpA) of Mycobacterium tuberculosis. This monoclonal antibody (MAb) belongs to the IgG2b isotype and exhibits high titers of 1:2,048,000 to the antigen. The cell infection assays demonstrated that antibody protection was achieved by promoting opsonophagocytosis in a dose-dependent manner, enhancing phagosome-lysosome fusion, and inhibiting mycobacterial intracellular growth in vitro and ex vivo. Cytotoxicity assays, animal toxicity analyses, and pharmacokinetic evaluations confirmed the safety and sustained effectiveness of the antibody in vivo. Furthermore, the mAb 1E1 can reduce the organs' bacterial burdens and pathological damages in the prevention mouse model as well as the treatment models. Above all, in this study, we found a novel mAb named 1E1 with IgG2b isotype targeting OmpA can have protection against tuberculosis (TB) in mice, which may serve as a treatment strategy for drug-resistant TB and a promising antigen for TB vaccine development.https://journals.asm.org/doi/10.1128/spectrum.02942-24tuberculosishumoral immunitymonoclonal antibodyOmpAphagocytosis
spellingShingle Huoming Li
Jiahong Ji
Mengjin Qu
Xiuling Ma
You Zuo
Minghui Tang
Lingyuan Zeng
Hao Li
Isolation and characterization of a protective monoclonal antibody targeting outer membrane protein (OmpA) against tuberculosis
Microbiology Spectrum
tuberculosis
humoral immunity
monoclonal antibody
OmpA
phagocytosis
title Isolation and characterization of a protective monoclonal antibody targeting outer membrane protein (OmpA) against tuberculosis
title_full Isolation and characterization of a protective monoclonal antibody targeting outer membrane protein (OmpA) against tuberculosis
title_fullStr Isolation and characterization of a protective monoclonal antibody targeting outer membrane protein (OmpA) against tuberculosis
title_full_unstemmed Isolation and characterization of a protective monoclonal antibody targeting outer membrane protein (OmpA) against tuberculosis
title_short Isolation and characterization of a protective monoclonal antibody targeting outer membrane protein (OmpA) against tuberculosis
title_sort isolation and characterization of a protective monoclonal antibody targeting outer membrane protein ompa against tuberculosis
topic tuberculosis
humoral immunity
monoclonal antibody
OmpA
phagocytosis
url https://journals.asm.org/doi/10.1128/spectrum.02942-24
work_keys_str_mv AT huomingli isolationandcharacterizationofaprotectivemonoclonalantibodytargetingoutermembraneproteinompaagainsttuberculosis
AT jiahongji isolationandcharacterizationofaprotectivemonoclonalantibodytargetingoutermembraneproteinompaagainsttuberculosis
AT mengjinqu isolationandcharacterizationofaprotectivemonoclonalantibodytargetingoutermembraneproteinompaagainsttuberculosis
AT xiulingma isolationandcharacterizationofaprotectivemonoclonalantibodytargetingoutermembraneproteinompaagainsttuberculosis
AT youzuo isolationandcharacterizationofaprotectivemonoclonalantibodytargetingoutermembraneproteinompaagainsttuberculosis
AT minghuitang isolationandcharacterizationofaprotectivemonoclonalantibodytargetingoutermembraneproteinompaagainsttuberculosis
AT lingyuanzeng isolationandcharacterizationofaprotectivemonoclonalantibodytargetingoutermembraneproteinompaagainsttuberculosis
AT haoli isolationandcharacterizationofaprotectivemonoclonalantibodytargetingoutermembraneproteinompaagainsttuberculosis