title: Postnatal development of intra-epithelial leukocytes in the chicken digestive tract: phenotypical characterization in situ.
abstract: In the present study, we characterized intra-epithelial leukocytes in the digestive tract of chickens during postnatal development. Their phenotype was characterized by monoclonal antibodies in cryostat sections and the numbers of the different cell-types were counted in the epithelium of the esophagus, proventriculus, duodenum, jejunum, cecum, and colon. All intra-epithelial leukocytes bore the leukocyte-common antigen CD45; 35% were T lymphocytes, and 50% bore a B-cell marker. However, no immunoglobulin-bearing cells were detected in the epithelium. Monocytes and macrophages were found only in the epithelium of the esophagus. A remaining population of non-B, non-T, non-monocyte cells (15%) was present in all parts of the digestive tract. The number of intra-epithelial leukocytes was greatest in the duodenum and jejunum, and decreased in the proximal part of the cecum and in the colon. Intra-epithelial leukocytes were only sporadically detected in the proventriculus. The total number of intra-epithelial leukocytes increased until 8 weeks after hatching and then decreased at 18 months. In the esophagus, the total number of intra-epithelial leukocytes changed little during aging. We found that the intra-epithelial leukocytes of chickens and rodents are distinct in that chicken intra-epithelial leukocytes comprise a cell population that bears a B-cell antigen but that lacks surface immunoglobulins.
authors.affiliation: Central Veterinary Institute, Department of Virology, Lelystad, The Netherlands.
authors.forename: L
authors.initials: L
authors.lastname: Vervelde
authors.forename: S H
authors.initials: SH
authors.lastname: Jeurissen
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000943:Antigens, Differentiation / Q000032:analysis; D002452:Cell Count; D002645:Chickens / Q000033:anatomy & histology* / Q000254:growth & development; D004064:Digestive System / Q000166:cytology / Q000254:growth & development / Q000276:immunology*; D004847:Epithelial Cells; D004848:Epithelium / Q000276:immunology; D016130:Immunophenotyping; D007962:Leukocytes / Q000166:cytology*; D008221:Lymphoid Tissue / Q000166:cytology / Q000254:growth & development*; D012377:Rodentia / Q000033:anatomy & histology; D013045:Species Specificity
chemical_list: D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation