<abstract xmlns="http://www.w3.org/1999/xhtml"> Background: IgA1 protease may enhance the bacterial infection in human beings. However, the molecular mechanism of bacterial adherence to eukaryotic cells is unclear.Objective: Reveal the mechanisms of IgA1 protease-dependent and non-protease bacterial adherence to eukaryotic cells.Method: Type I and type II IgA1 proteases from iga genes (GenBank DQ683355 for NTHi465, DQ683356 for NTHi500 and DQ683357 for Nm430) were cloned, expressed, and purified. Cellular assays for adherence of IgA1 protease-producing and -non-producing and typable and nontypable strains of H. influenzae to human lung carcinoma cells (A549) were carried out in the presence of human antibodies.Results: Adherence of protease-producing strains and non-producing strains to human epithelial cells was significantly dependent on the enzyme activity. In addition, human IgG was an inhibitor to IgA1 proteasedependent adherence of H. influenzae strains to human cells. However, IgA1 antibodies were irrelevant to IgA1 protease-dependent adherence.Conclusion: IgA1 protease was required for adherence of pathogenic bacteria to human epithelial cells in IgA1 protease-producing bacteria, and human IgG inhibits the adherence, but not for IgA1 protease non-producing bacteria.</abstract>

Background: IgA1 protease may enhance the bacterial infection in human beings. However, the molecular mechanism of bacterial adherence to eukaryotic cells is unclear.Objective: Reveal the mechanisms of IgA1 protease-dependent and non-protease bacterial adherence to eukaryotic cells.Method: Type I and type II IgA1 proteases from iga genes (GenBank DQ683355 for NTHi465, DQ683356 for NTHi500 and DQ683357 for Nm430) were cloned, expressed, and purified. Cellular assays for adherence of IgA1 protease-producing and -non-producing and typable and nontypable strains of H. influenzae to human lung carcinoma cells (A549) were carried out in the presence of human antibodies.Results: Adherence of protease-producing strains and non-producing strains to human epithelial cells was significantly dependent on the enzyme activity. In addition, human IgG was an inhibitor to IgA1 proteasedependent adherence of H. influenzae strains to human cells. However, IgA1 antibodies were irrelevant to IgA1 protease-dependent adherence.Conclusion: IgA1 protease was required for adherence of pathogenic bacteria to human epithelial cells in IgA1 protease-producing bacteria, and human IgG inhibits the adherence, but not for IgA1 protease non-producing bacteria.

Human IgG inhibits IgA1 protease-dependent adherence of Haemophilus influenza strains to human lung epithelial cells

Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung 804,

Department of Parasitology, School of Medicine, China Medical University, Taichung 40402,

Asian Biomedicine

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Background: IgA1 protease may enhance the bacterial infection in human beings. However, the molecular mechanism of bacterial adherence to eukaryotic cells is...

Human IgG inhibits IgA1 protease-dependent adherence of Haemophilus influenza strains to human lung epithelial cells

Article Category: Original article

Published Online: Feb 04, 2017

Page range: 45 - 56

DOI: https://doi.org/10.5372/1905-7415.0501.005

Keywords
Cellular adherence, iga gene, IgA1 protease subtypes, IgG inhibition, Neisseria meningitides, typable and nontypable Haemophilus influenzae (THi and NTHi)

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Human IgG inhibits IgA1 protease-dependent adherence of Haemophilus influenza strains to human lung epithelial cells

Article Category: Original article

Published Online: Feb 04, 2017

Page range: 45 - 56

DOI: https://doi.org/10.5372/1905-7415.0501.005

KeywordsCellular adherence, iga gene, IgA1 protease subtypes, IgG inhibition, Neisseria meningitides, typable and nontypable Haemophilus influenzae (THi and NTHi)

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
Cellular adherence, iga gene, IgA1 protease subtypes, IgG inhibition, Neisseria meningitides, typable and nontypable Haemophilus influenzae (THi and NTHi)