The probe external to the targeting construct and used to screen ES cells and mice, which distinguishes the 6 Kb wild type and 8
The probe external to the targeting construct and used to screen ES cells and mice, which distinguishes the 6 Kb wild type and 8.8 Kb targeted alleles after Sac I digestion, is indicated. importance to sponsor survival. Safety of mucosal surfaces is dependent on efficient homing and build up of effector and T cells, as well as antibody secreting B cells (ASCs)4. Immunoglobulin (Ig) A is the most common antibody isotype involved in the protection of human being and mouse mucosal surfaces. In the gastrointestinal tract, IgA ASC accumulate in the lamina propria, where they secrete antibodies that are transcytosed PMSF across the PMSF intestinal epithelium into the lumen. Secreted IgA antibodies bind and neutralize pathogens and toxins within mucosal epithelial cells and within the gut lumen, thus affording mucosal immune protection to the host (1-3). Infants are given birth to with na?ve immune systems, and are thus at increased risk of infection until their immune system generates memory/effector lymphocytes. Passive immune protection of the newborn gastrointestinal tract is dependent on an active process of IgA ASC accumulation in the lactating mammary gland of the mother (4, 5-7). Through this process, IgA antibodies specific to pathogens in the mother’s environment are secreted into the milk and passively transferred to the gut of the suckling neonate. This process provides the infant with antigen-specific protection against gastrointestinal pathogens previously encountered by the mother (8). PMSF The efficient migration and accumulation of lymphocytes is usually highly dependent on tissue-expressed chemokines and leukocyte-expressed chemokine receptors. The chemokine receptor CCR10 is usually thought to help direct subsets of lymphocytes to mucosal and cutaneous tissues via interactions with the chemokines CCL28 and CCL27, respectively. However, this hypothesis is based not on studies of CCR10 itself, but rather on studies using neutralizing antibodies against CCL27 and CCL28 (7, 9-13). Complicating the study of CCR10/ligand interactions is usually data suggesting the conversation of CCL28 with CCR3 (14, 15). CCL28 and CCL27 could also bind additional chemokine receptors through interactions that have not yet been characterized. IgA ASCs have been hypothesized to traffic to multiple mucosal sites via a common mucosal immune system (16). Such a system would afford protection to a broad spectrum of mucosal tissues after immunization to a single mucosal site. Evidence for the common mucosal immune system is usually partly based on data Rabbit Polyclonal to EGFR (phospho-Ser1071) showing that IgA immunoblasts collected from mesenteric lymph nodes efficiently seed the gastrointestinal tract, mammary gland, respiratory tract, and genital tract (16). CCR10 interactions are of particular interest to mucosal immunity in that CCL28 is usually expressed in a broad range of mucosal tissues, and has been hypothesized to act as a unifying factor in the common mucosal immune system (14, 17). In an effort to define the role of CCR10 in lymphocyte homing to mucosal tissues, we selected a direct approach: targeted deletion of CCR10 expression in mice. Here we describe the engineering of mice genetically deficient in functional CCR10. The role of CCR10-mediated homing was then tested using a lactating mouse mammary gland model. This model is usually ideal in that IgA ASC isolated from your mammary gland have been shown to lack mRNA expression of the other reported CCL28 receptor CCR3, and IgA ASC accumulation in the lactating mammary gland requires CCL28-mediated interactions (7). Using CCR10 deficient mice, we demonstrate that CCR10 interactions are indispensable for efficient accumulation of high levels of IgA ASC in the lactating mammary gland. Conversely, homing PMSF of IgA ASCs to the large intestine, a site of abundant CCL28 expression is usually minimally impacted in CCR10-/- mice. The use of CCR10 deficient mice will allow characterization of the role of this chemokine receptor in other immune functions, as well as in models of inflammation and disease. Materials and Methods Construction of the EGFP-containing targeting vector A pBluescript SK(+) plasmid made up of a 5.8 Kb murine CCR10 genomic DNA clone (18) PMSF was used to generate the targeting construct. The existing EcoRV site was removed using EcoRV and ClaI, and the first ATG codon of CCR10 exon I was mutated into a new EcoRV restriction site via PCR-directed mutagenesis (QuickChange? site-directed mutagenesis kit, Stratagene, La Jolla, CA). The enhanced green fluorescent protein (EGFP) gene (including its SV40 polyA sequence, and excluding its CMV promoter) was excised from a pEGFP-N1 plasmid using NheI and AflII, and inserted into a pBluescript SK(+) plasmid. The NeoR gene was removed from a pPNT plasmid using NotI and EcoRI and inserted into the EGFP-containing pBluescript SK(+) plasmid immediately downstream from EGFP to create a 1.8 Kb EGFP/NeoR cassette. The plasmid made up of the.