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PASSIVE IMMUNITY Immunoglobuline of milk and whey, especially from colostrum, have been suggeted to assist in the development of passive immunity
Immunoglobulins are well recognized to provide disease protection to new-born through passive immunity and there is evidence that the immunoglobulins also may have a role in disease control in adults. Relatively few studies have been made concerning the incidence and specificity of immunoglobulins in commercial milk supplies. Li Chan et al. (1994) reported on the IgG concentration of 254 raw milk samples collected from the Province of British Columbia over a two-year period. The IgG values varied from 0.03 to 0.71 mg/ml, with media values of about ~.25mg/ml. There were significant differences in values of the levels of IgG among the milks from the 14 different dairies and the IgG values from the same dairy varied from one year to the next. These findings suggest that milk from a large number of cows, as would be found in the milk from commercial dairies, will have activity against a wide range of different bacteria, although the level of activity may vary from year to year and with geographical location. Using ELISA testing, all of the milks showed measurable antibody binding activity against the lipopolysaccharide (LPS) fraction of 5 different bacteria (Shigella flexneri 1A, Escherichia coli 0111:B4, Escherichia coli 0128:B12; Salmonella typhonerium and Salmonella enteritidis). Immunization of cows with the 5 organisms gave a significant increase in the LPS activity only for the S. enteritidis in relation to any of the commercial raw milk samples. The activities for the other four organisms were about the same. The number of specific immunoglobulins in the whey from commercial milk supplies is not known, but will reflect the exposure of the cows to antigens in their natural environment. Where a given milk supply represents milk from thousands of individual cows, it is to be expected that there will be a wide range of different immunoglobulins present -- the type and levels of which would be expected to vary widely. It is known that whey protein concentrates, treated to avoid denaturation., from mixed milk supplies generally contain sufficient antibody to E. coli K-99 to meet the requirements of the USDA to serve as a colostrum supplement. Hyper-immune Milk/Whey: Immunization of cows with specific antibodies has been practiced for a number of years on a limited basis, with the resulting milk being characterised as "hyper-immune milk". Some ‘immune milk has been produced and marketed in Asian countries (Hilpert, 1980). Korhonen (1988) reviewed that status of immune milk clinical trials and suggested that "immune" milk, targeted to specific consumer groups, might play a significant role in the future. The extent of the increase in specific activity of the antibodies appears to be dependent upon the specific organism and agent used for vaccination. Li Chan, et al. (1994) found increased ELISA activity for only one of five bacterial antigens in immunized cows, in comparison to the levels of activity in milk from commercial dairies. Losso et al. (1994) compared milk from immumized cows with milk from non-immunized cows and found that 40% of the non-immunized cows were not different in antigen binding activity from those that were immunized. Tomita et al. (1995) vaccinated cows with a lipopolysaccharide-protein conjugate derived from E. coli J5. Immunization did enhance serum antibody titer to J5, but did not enhance whey IgG titers. Ormrod and Miller (1991) reported the isolation of a low molecular weight fraction of the milk of dairy cows immunized with a multivariate bacterial vaccine which was shown to have anti-inflammatory activity in the rat hind-paw oedema assay. Kobayashi, et al. (1991) and Ishida, et al. (1992) showed that ‘immune’ milk, obtained from cows immunized with a mix bacteria flora, showed a higher survival rate for mice given lethal doses of irradiation as compared to control mice not receiving the ‘immune’ milk. Concentration of IgA in a cell culture derived from Peyer’s patches, mesenteric lymph node and spleen was higher from mice given the ‘immune’ milk than for the control mice. Several studies have suggested that feeding immune milk increases antibodies against the immunizing bacteria and may reduce disease (Murosaki et al. (1991); Chernokhvostova et al. 1990; Boedeker et al. 1987). In one study reducing the level of free energy intake by 60% appeared to eliminate the differences between B/W mice fed immune and control skim milk. Immune milk has also been suggested to lower blood pressure in a clinical trial in a double blind study (Sharpe et al. 1994). No change was noted in high density lipoprotein cholesterol or triglycerides. However, the immune milk significantly lowered systolic and diastolic blood pressure. References: Otani-H 1998 Production and utilization of bovine milk
immunoglobulins specific to pathogenic microorganisms. Milk-Science; 47 (2) 63-75 To be completed
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