The Mechanism of Transfer of Immunoglobulin Into Mammary Secretion of Cows

Abstract

Summary. Changes in the concentration of IgG^. IgC,, IgM, IgA and albumin in semm and mammary secretion were studied in 15 cows and 2 heifers before and after parturition. Concentrations of IgGj and IgC, in blood serum 3-5 weeks before parturition were 13-38 ± 0-75 and 10-08 ±: 0 39 mg/ml (means ± S.E.) respectively. In all animaLs tlie cfinc-entration of IgC, in serum decreased abruptly, usually by more than 50%, 2-3 weeks before parturition, and during the same period the concentrations of IgC2, IgM, IgA and albumin in seriun remained unchanged. Four weeks after parturition the concentration of IjiC, in serum had returned to values similar to tho.se observed prior to the abrupt fall.Five weeks before parturition the concentration of IgGj in mammary secretion was, on average, 11 times higher than that of IgC^. Highest concentrations of IgGj in secretion (113-89 rt 11-41 nig/ml) were obser^-ed 2-3 vi'eeks before parhirition in 16 of the 17 animals. The concentration of IgG., over the 5 weeks prior to parturition remained unchanged at levels of approx 30X of comparable values in seruui. Concei trations of IgM (11-8.^ ± 0-53) and IgA (3-80 it 0-20) in secretion collected prior to antl immediately afler parturition were, on average. 2 and 7 times higher respectively than those in serum."Hie sharp fall in the concentration of IgG, in serum in the absence of any suggestion of a concomitant decrease in IgGg concentration .strongly suggests that the degradation hypothesis proposed by Brambell (1958Brambell ( . 1966 for selective transfer of protein across epithelial membranes does not hold for the mammary gland of the cow. The results support an allernative hypothesis based on the existence of IgGj-specific receptor sites located on the basal or intercellular membrane of the glandular epitlieL'al cells.

Comparisons of Immunoglobulin Secretion in the Salivary and Mammary Glands of Sheep

“…The selective index for IgA in parotid saliva is not significantly different from that obtained for milk from non-immunized glands of ewes in mid-lactation (Watson and Lascelles, 1973), whereas the higher selective index for IgA in milk from immunized glands of these ewes was significantly lower than that obtained for non-parotid saliva. This lends support to our earlier suggestion (Watson and Lascelles, 1971) that, whereas the non-parotid salivary glands are being subjected constantly to antigenie stimulation, the continuous flow of large quantities of parotid saliva ensures that the parotid gland receives relatively little local antigenie stimulation.…”

“…Brandon, Watson and Lascelles, 1971). The selective indices for IgGj were around 2 for both parotid and non-parotid glands, which is similar to results obtained for the lactating mammary gland by Mackenzie and Lascelles (1968) who measured the distribution of i^ii-labelled IgGj^ and IgG2 between blood and milk in lactating ewes.…”

Effects of Induction of Parturition in Ewes with Dexamethasone or Oestrogen on Concentrations of Immunoglobulins in Colostrum, and Absorption of Immunoglobulins by Lambs

“…Concentrations of the immunoglobulins IgGh IgGz, IgM and 19A in lamb plasma and colostral whey were determined as described by Brandon et al (1971) using the single radial immunodiffusion technique (Mancini et al 1965).…”

Production and characterization of monoclonal antibodies anti fragment Fc of bovine IgG

“…The IgG1 displays unique characteristics: a) it constitutes 90% of the colostral immunoglobulins, providing neonatal protection as well as instructions for the action of the immune system. (Butler et al, 1972;Butler et al, 1974;Guidry et al, 1980); b) it is selectively transported by the FcRn, a receptor which is found in the lung alveolar and mammary gland epithelium (Dyxon et al, 1961;Kemler et al, 1965;Brandon et al, 1971); c) it binds to neutrophils such as IgG2 (Mcguire et al, 1979;Butler et al, 1985); d) it is synthesized locally and released as a secretory immunoglobulin on the mucosa (Brandon et al, 1971;Butler et al, 1985). Different allotypes among animals of the same species correspond to the capacity of influencing the immune system and/or creating resistance to viral and bacterial infections.…”