Functional Activities of O-Polysaccharide and Hemolysin Coregulated Protein 1 Specific Antibodies Isolated from Melioidosis Patients

Melioidosis is a fatal tropical disease caused by the environmental Gram-negative bacterium, Burkholderia pseudomallei. This bacterium is intrinsically resistant to several antibiotics and treatment of melioidosis requires prolonged antibiotic administration. To date, there are no vaccines available for melioidosis. Previous studies have shown that humoral immunity is critical for surviving melioidosis and that O-polysaccharide (OPS) and hemolysin coregulated protein 1 (Hcp1) are important protective antigens in animal models of melioidosis. Our previous studies revealed that melioidosis patients had high levels of OPS- and Hcp1-specific antibodies and that IgG against OPS (IgG-OPS) and Hcp1 (IgG-Hcp1) were associated with patient survival. In this study, we characterized the potential function(s) of IgG-OPS and IgG-Hcp1 from melioidosis patients. IgG-OPS and IgG-Hcp1 were purified from pooled serum obtained from melioidosis patients using immuno-affinity chromatography. Antibody-dependent cellular phagocytosis assays were performed with pooled serum from melioidosis patients and compared with serum obtained from healthy controls. Serum from melioidosis patients significantly enhanced B. pseudomallei uptake into the human monocytic cell line THP-1 compared with pooled serum from healthy donors. Enhanced opsonization was observed with IgG-OPS and IgG-Hcp1 in a dose-dependent manner. Antibody-dependent complement deposition assays were performed with IgG-OPS and IgG-Hcp1 using flow cytometry and showed that there was enhanced C3b deposition on the surface of B. pseudomallei treated with IgG-OPS but to a lesser degree with IgG-Hcp1. This study provides insight into the function of IgG-OPS and IgG-Hcp1 in human melioidosis and supports that OPS and Hcp1 are potential vaccine antigens for immunization against melioidosis.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:90

Enthalten in:

Infection and immunity - 90(2022), 11 vom: 17. Nov., Seite e0021422

Sprache:

Englisch

Beteiligte Personen:

Pumpuang, Apinya [VerfasserIn]
Paksanont, Suporn [VerfasserIn]
Burtnick, Mary N [VerfasserIn]
Brett, Paul J [VerfasserIn]
Chantratita, Narisara [VerfasserIn]

Links:

Volltext

Themen:

ADCD
ADCP
Antibodies, Bacterial
Antibody function
Antigen
Burkholderia pseudomallei
Hcp1
Hemolysin Proteins
Immunoglobulin G
Journal Article
Melioidosis
O-polysaccharide
Opsonization
Polysaccharides
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Vaccine

Anmerkungen:

Date Completed 23.11.2022

Date Revised 28.11.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1128/iai.00214-22

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM347420508