Host cell interactions of novel antigenic membrane proteins of Mycoplasma agalactiae

Author(s)

Barbosa, Maysa Santos ; Marques, Lucas Miranda ; Timenetsky, Jorge ; Rosengarten, Renate ; Spergser, Joachim ; Chopra-Dewasthaly, Rohini

• Document type: Journal article
• Source: BMC Microbiology; v. 22, n. 1, p. 13-pg., 2022-04-08.

Abstract

Background Mycoplasma agalactiae is the main etiological agent of Contagious Agalactia syndrome of small ruminants notifiable to the World Organization for Animal Health. Despite serious economic losses, successful vaccines are unavailable, largely because its colonization and invasion factors are not well understood. This study evaluates the role of two recently identified antigenic proteins (MAG_1560, MAG_6130) and the cytadhesin P40 in pathogenicity related phenotypes. Results Adhesion to HeLa and sheep primary mammary stromal cells (MSC) was evaluated using ELISA, as well as in vitro adhesion assays on monolayer cell cultures. The results demonstrated MAG_6130 as a novel adhesin of M. agalactiae whose capacity to adhere to eukaryotic cells was significantly reduced by specific antiserum. Additionally, these proteins exhibited significant binding to plasminogen and extracellular matrix (ECM) proteins like lactoferrin, fibrinogen and fibronectin, a feature that could potentially support the pathogen in host colonization, tissue migration and immune evasion. Furthermore, these proteins played a detrimental role on the host cell proliferation and viability and were observed to activate pro-apoptotic genes indicating their involvement in cell death when eukaryotic cells were infected with M. agalactiae. Conclusions To summarize, the hypothetical protein corresponding to MAG_6130 has not only been assigned novel adhesion functions but together with P40 it is demonstrated for the first time to bind to lactoferrin and ECM proteins thereby playing important roles in host colonization and pathogenicity. (AU)

• FAPESP's process: 17/25686-3 - Development of diagnostic test and selection of vaccine candidates for mycoplasmosis in cattle and goats
• Grantee: Jorge Timenetsky
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/03425-9 - Antigenic characterization of the membrane proteins of Mycoplasma agalactiae and them role in virulence and pathogenicity in vitro
• Grantee: Maysa Santos Barbosa
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 16/23306-6 - Functional characterization and evaluation of the antigenicity and immunogenicity of recombinant proteins of Mycoplasma agalactiae
• Grantee: Maysa Santos Barbosa
• Support Opportunities: Scholarships in Brazil - Doctorate