Written by Greg Arnold, DC, CSCS. Mice who received an injection of M. tuberculosis that was first exposed to IgA before injection had 24.5% of lung area affected by M. tuberculosis compared to 65% in the control group. Those mice who were first injected with IgA, then M. tuberculosis had 31% of lung area affected compared to 65% in the control group.

In a 2013 study (1), 60 mice were divide into three groups (20 mice per group):

• Control mice were infected with tuberculsosis through an injection of 2.5 x 105 colony-forming units of the bacterium Mycobacterium tuberculosis
• Colostrum-first mice were injected with 1 milligram of a protein found in colostrum called IgA (1 milligrams in 50 milliliters of saline solution) and then injected with M. tuberculosis 2 hours later
• Colostrum/Tuberculosis mice were injected with a solution of M. tuberculosis that was first exposed to IgA before being injected into the mice.

After 60 days, lung tissue samples of Colostrum/Tuberculosis mice had 62.3% less lung area affected by tuberculosis than the control group (24.5 vs 65% pneumonic area in the lungs, p < 0.0001) while colostrum-first mice had 52.4% less lung tissue affected compared to the control group (31% vs 65%, p < 0.05).

Citing the ability of the IgA protein in colostrum to possess a number of disease-preventing actions that include “neutralizing antigens and viruses…and preventing the adherence of pathogens to [lung] surfaces (2)”, the researchers concluded that “Our results demonstrated for the first time the prophylactic effect of mucosal administration of IgA obtained from human colostrum in a mouse model of infection with M. tuberculosis.”

Source: Alvarez, Nadine, et al. “Passive administration of purified secretory IgA from human colostrum induces protection against Mycobacterium tuberculosis in a murine model of progressive pulmonary infection.” BMC immunology 14.1 (2013): S3.

© 2013 Alvarez et al; licensee BioMed Central Ltd. Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0)

Posted March 23, 2015.

References:

1. Alvarez N. Passive administration of purified secretory IgA from human colostrum induces protection against Mycobacterium tuberculosis in a murine model of progressive pulmonary infection. BMC Immunol 2013;14 Suppl 1:S3. doi: 10.1186/1471-2172-14-S1-S3. Epub 2013 Feb 25.
2. Brandtzaeg P: Mucosal immunity: integration between mother and the breast-fed infant. Vaccine 2003, 2:3382-3388