Article

Cloning and characterization of the bovine polymeric immunoglobulin receptor-encoding cDNA.

Leiden Institute of Chemistry, Medical Biotechnology Department, Gorlaeus Laboratories, Leiden University, The Netherlands.
Gene (Impact Factor: 2.08). 11/1995; 164(2):329-33. DOI: 10.1016/0378-1119(95)00520-G
Source: PubMed

ABSTRACT Trans-epithelial transport of polymeric immunoglobulins (pIg) into mucosal and glandular secretions is carried out by the pIg receptor (pIgR). Therefore, expression of the pIgR gene in epithelial cells of mucosal and glandular tissues is an absolute requirement for achieving mucosal immunity. We report the cloning and characterization of the bovine pIgR cDNA. Three overlapping cDNA clones with a total length of 3608 bp yielded an open reading frame encoding a 757-amino-acid (aa) transmembrane (TM) glycoprotein. Although polymorphism was found in two separate clones, Northern blot analysis showed a single pIgR mRNA (approx. 3.8 kb) to be present in the mammary gland, liver, lung, kidney and intestine of a lactating cow. There was no detectable expression of pIgR in the spleen of the same animal. Comparison of the deduced bovine pIgR as sequence with those of rat, mouse, man and rabbit shows that this receptor is highly conserved both in aa sequence and structural organization. The degree of conservation in the TM sequence and the C-terminal cytoplasmic tail, which contains the various signals for intracellular trafficking of the receptor, is 65-73%. We also find a high degree of conservation (61-66%) in the ectoplasmic part of the receptor, known as the secretory component (SC), with an exception for that of the rabbit SC, which is much lower (47%). Among the five Ig-like domains in the SC, the N-terminal domain I, where the primary pIg-binding site is located, showed the highest (72-83%) aa sequence conservation.

0 Bookmarks
 · 
52 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: The mucosal surfaces lining the gastrointestinal, respiratory and genitourinary tracts are continuously bombarded by potentially infectious agents such as bacteria, viruses, fungi, and parasites, in addition to soluble dietary and environmental substances. The first line of specific immunological defense against these environmental antigens is secretory IgA (SIgA) (Brandtzaeg et al., 1997; Lamm, 1997), which is produced by selective transport of polymeric IgA (pIgA) across epithelial cells lining mucosal surfaces (Kaetzel, 2005; Kaetzel and Mostov, 2005; Norderhaug et al., 1999). The magnitude of this transport process is impressive; it has been estimated that ~3 g of SIgA are transported daily into the intestines of the average adult (Conley and Delacroix, 1987; Mestecky et al., 1986). Transport of polymeric immunoglobulins (IgA and, to a lesser extent, IgM) across mucosal epithelial cells is mediated by a transmembrane glycoprotein called the polymeric immunoglobulin receptor (pIgR).
    01/1970: pages 43-89;
  • [Show abstract] [Hide abstract]
    ABSTRACT: The submandibular and parotid glands are the main sources of immunoglobulins A (IgAs) in human and rat saliva. These glands express the polymeric immunoglobulin receptor (pIgR), which transports IgAs into saliva. The main source of IgAs in saliva and pIgR expression in salivary glands has not been well documented in cattle. Expressions of pIgR were determined in the major bovine salivary glands (sublingual, submandibular, and parotid) by RT-PCR for mRNA and by Western blot analysis and immunohistochemistry (IHC) using an anti-human pIgR antibody for protein. The protein detected with the antibody was identified by nano-liquid chromatography-quadrupole time of flight mass spectrometry. Additionally, the distribution of Ig-producing plasma cells was analyzed by IHC. RT-PCR showed that pIgR was expressed in the sublingual and submandibular glands, but not in the parotid gland. Higher protein levels were observed in sublingual glands than in submandibular glands by Western blot. By IHC, pIgR was mainly located on the apical side of the cytoplasmic membrane in the sublingual gland, whereas it was observed only on the basal side in the submandibular gland. The highest density of plasma cells expressing IgAs was observed in the sublingual gland. These results suggest that the sublingual gland plays an important role in first-line defence of the oral cavity in cattle in contrast to humans and rats.
    The Veterinary Journal 02/2013; · 2.17 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Immunoglobulin (Ig) E is actively transported into ovine colostrum. Here we examine the degree of selectivity and the mechanism by which this transfer occurs in sheep. Results indicate that during colostrogenesis in sheep, transfer of immunoglobulins was most selective for IgG1 and IgA followed by IgE, IgM and IgG2. In milk, selectivity was greatest for IgA, followed by IgM, IgE, IgG1 and IgG2. The neonatal Fc receptor (FcRn) and poly immunoglobulin receptor (pIgR) mediate the transport of IgG1 and IgA across the ovine mammary epithelium respectively. In primates and rodents, the low-affinity IgE receptor, Fc epsilonRII, functions to transport IgE across the intestinal epithelium. We therefore investigated the expression of the low-affinity IgE receptor (CD23), pIgR and FcRn transcripts in the ovine mammary gland. The expression profiles of FcRn, pIgR and CD23 mRNA reflected concentrations of their Ig ligands in mammary secretions. These findings suggest a role for CD23 in transport of IgE across the mammary epithelium of sheep.
    Research in Veterinary Science 03/2010; 89(2):184-90. · 1.51 Impact Factor