title: Postnatal development of lung T lymphocytes in a porcine model.
abstract: OBJECTIVE
  Despite the high prevalence of respiratory diseases in the world and the extensive information available on the mucosal immune system, research on the development of the lung immune system in humans is limited by technical and ethical considerations; therefore, we studied the postnatal development of T lymphocytes in lung lobes in a porcine model.
  
  
  METHODS
  Using less than 36-hour-old (NB), 1-week-weaned (5-week-old -AW-), 3-month-old (3M), and 4-year-old (4YR) healthy, nonvaccinated, specific pathogen free (SPF) Vietnamese miniature pigs, we studied the CD3+, CD4+, CD8+, TCR1 (gamma-delta T cells), and CD25+ (IL-2R-alpha) cell subpopulations in lung lobes parenchyma, bronchoalveolar lavage (BAL), peripheral blood mononuclear cells (PBMC), and cervical lymph nodes (LN) by flow cytometry.
  
  
  RESULTS
  No differences among lung lobes were detected in any of the cell subpopulations tested. A low proportion of T cell subsets was detected in NB and 4YR groups in lung and BAL. Besides, the AW and 3M groups showed important changes in T cell subpopulations.
  
  
  CONCLUSIONS
  These results suggest that in healthy animals the lung lobes behave as a homogeneous immune organ. T cells were detected in very low percentages at birth and in adult life, which may explain the high susceptibility to respiratory infections both early and later in life. Postweaning antigenic challenges and endocrine and sexual maturity at 3M had important effects on the development of the mucosal immune system. It was also evident that changes at mucosal sites were poorly correlated with PBMC and LN.
authors.affiliation: Laboratorio de Inmunobiología de las Mucosas, Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Avenida Instituto Politécnico Nacional # 2508 Colonia Zacatenco, 07360, México, D.F, Mexico.
authors.forename: Angel J
authors.initials: AJ
authors.lastname: Balam-May
authors.forename: Carmen
authors.initials: C
authors.lastname: Ramírez-Estudillo
authors.forename: Gloria
authors.initials: G
authors.lastname: Lazo-Vázquez
authors.forename: Marco A
authors.initials: MA
authors.lastname: Vega-López
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D015415:Biomarkers / Q000378:metabolism; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology; D005434:Flow Cytometry; D018928:Immunity, Mucosal; D016130:Immunophenotyping / Q000379:methods; D008168:Lung / Q000166:cytology / Q000254:growth & development / Q000276:immunology* / Q000378:metabolism; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology; D023421:Models, Animal; D013552:Swine; D013556:Swine, Miniature; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D014886:Weaning
chemical_list: D015415:Biomarkers