Passive administration of purified secretory IgA from human colostrum induces protection against Mycobacterium tuberculosis in a murine model of progressive pulmonary infection

Nadine Alvarez,Rogelio Hernández-Pando,Alicia Aguilar,Yanely Tirado,Armando Cádiz,María E Sarmiento,Axel Cervantes,Frank Camacho,Cesar Rivas,Armando Acosta,Reinier Borrero,Alina Puig,Mohd Nor Norazmi,Oscar Otero,Gustavo Falero-Díaz

doi:10.1186/1471-2172-14-s1-s3

Abstract

BackgroundImmunoglobulin A is the most abundant isotype in secretions from mucosal surfaces of the gastrointestinal, respiratory and genitourinary tracts and in external secretions such as colostrum, breast milk, tears and saliva. The high concentration of human secretory IgA (hsIgA) in human colostrum strongly suggests that it should play an important role in the passive immune protection against gastrointestinal and respiratory infections.Materials and methodsHuman secretory IgA was purified from colostrum. The reactivity of hsIgA against mycobacterial antigens and its protective capacity against mycobacterial infection was evaluated.ResultsThe passive administration of hsIgA reduces the pneumonic area before challenge with M. tuberculosis. The intratracheal administration of M. tuberculosis preincubated with hsIgA to mice greatly reduced the bacterial load in the lungs and diminished lung tissue injury.ConclusionsHsIgA purified from colostrum protects against M. tuberculosis infection in an experimental mouse model.

Highlights

Mucosal infections caused by intracellular pathogens induce cellular immune responses [1], mediated by CD4+ and CD8+ T cells, normally accompanied by the production of antibodies including the synthesis of human secretory immunoglobulin A, which provides a first important line of defense against invasion of pathogens into tissues [2]
The intratracheal administration of M. tuberculosis preincubated with human secretory IgA (hsIgA) to mice greatly reduced the bacterial load in the lungs and diminished lung tissue injury
HsIgA purified from colostrum protects against M. tuberculosis infection in an experimental mouse model

Summary

Results

The passive administration of hsIgA reduces the pneumonic area before challenge with M. tuberculosis. The intratracheal administration of M. tuberculosis preincubated with hsIgA to mice greatly reduced the bacterial load in the lungs and diminished lung tissue injury

Introduction

Materials and methods

Results and discussion