Detection of antibody specificity of raw bovine and human milk to bacterial lipopolysaccharides using PCFIA

Abstract

Raw milk from non-immunized cows and raw human milk from lactating mothers were examined for specificity and antibody activity against lipopolysaccharides (LPS) of five pathogenic bacteria, i.e. Escherichia coli O111:B4, E. coli O128:B12, Salmonella enteritidis, S. typhimurium and Shigella flexneri 1A in a particle concentration fluorescence immunoassay (PCFIA). Bacterial LPS was covalently coated on submicron polystyrene particles and used in an antibody sandwich technique with commercially available rabbit anti-bovine fluorescein-labeled IgG or goat anti-human fluorescein-labeled IgA. Comparison was made to a skim milk sample obtained from vaccinated cows. In general, specific activity of milk IgG against bacterial LPS did not parallel the trend of total non-specific activity. Although the specific anti-LPS activities were in general high in milk from vaccinated cows, milk from non-immunized cows also showed significant activity against the bacterial LPS, sometimes higher than the vaccinated cows. IgA in human milk samples showed a wider range of antibody activity against the LPS fractions than bovine milk samples. The specificity of antibody from milk obtained from non-immunized cows against pathogenic bacteria demonstrated that immunization of cows in order to obtain milk with high titer antibody may not be necessary as milk from non-immunized cows can provide IgG with sufficient antibody activity against the LPS of bacterial pathogens. This can translate into significant savings and reduce stress imposed on animals for immunization.

Milk immunoglobulins and complement factors

“…Also, raw milk from nonimmunised cows contains specific Igs to lipopolysaccharides from major human pathogenic bacteria, e.g. E. coli, Salmonella enteriditis, S. typhimurium and Shigella flexneri (Losso et al 1993). Further, natural antibodies to a colonisation factor antigen (CFA-1) of human enterotoxigenic E. coli have been found in normal colostrum and milk (Facon et al 1995).The specific antibodies in the colostrum of cows immunised with human pathogens have also been found to exert a synergistic effect on the activity of nonspecific antimicrobial factors such as lactoferrin and lysozyme (Takahashi et al 1992) as well as lactoperoxidase (Loimaranta et al 1998b).…”

Comparison of three immunosensor methods (surface plasmon resonance, screen-printed and classical amperometric immunosensors) for immunoglobulin G determination in human serum and animal or powdered milks

“…IgG) in the bioclinical field is very important owing to the anti-inflammatory action exerted by these proteins contained in serum and milk [1][2][3]. On the other hand, the increasing interest in exploiting the therapeutic action of IgG has stimulated the need for reliable assays for its determination at the endogenous level in serum and several kinds of milk [4][5][6]. The young of many mammalian species are born without an effective immune system, therefore the immunoglobulins exhibit antimicrobial activity and protect the neonate from infection until their own immune system has developed.…”