title: Development of hematological and immunological characteristics in neonatal rats.
abstract: As major immunological and hematological parameters evolve during the early period of life, laboratory data must be interpreted in relation to developmental changes. Wistar (WU) rats were sacrificed on PND2, 4, 7, 10, 14, 17 and 21. Peripheral blood, bone marrow, thymus samples and spleen cells were collected and a bronchoalveolar lavage (BAL) performed. Parameters of blood counts changed considerably between time points. IgM and IgG levels steadily increased. Spontaneous spleen cell proliferation was low before PND21, although mitogens had stimulatory effects above baseline. In the spleen, T-lymphocyte counts tripled by PND17 (mainly attributed to CD8(+) cytotoxic T-cells and CD4(+) T-helper cells). In peripheral blood an increase in B-lymphocytes to about 60% of the cell number was observed. In BAL fluid, macrophages represented 95-98% of the cells. In thymus architecture, lymphoblast migration was seen and epithelial structures appeared. The data presented will help to distinguish between maturational changes and treatment-related effects.
authors.affiliation: Fraunhofer Institute for Toxicology and Experimental Medicine, Nikolai-Fuchs-Strasse 1, 30625 Hannover, Germany.
authors.forename: Katherina
authors.initials: K
authors.lastname: Sewald
authors.affiliation: Fraunhofer Institute for Toxicology and Experimental Medicine, Nikolai-Fuchs-Strasse 1, 30625 Hannover, Germany.
authors.forename: Meike
authors.initials: M
authors.lastname: Mueller
authors.affiliation: Fraunhofer Institute for Toxicology and Experimental Medicine, Nikolai-Fuchs-Strasse 1, 30625 Hannover, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Buschmann
authors.affiliation: Fraunhofer Institute for Toxicology and Experimental Medicine, Nikolai-Fuchs-Strasse 1, 30625 Hannover, Germany.
authors.forename: Tanja
authors.initials: T
authors.lastname: Hansen
authors.affiliation: Fraunhofer Institute for Toxicology and Experimental Medicine, Nikolai-Fuchs-Strasse 1, 30625 Hannover, Germany. Electronic address: g.lewin@web.de.
authors.forename: Geertje
authors.initials: G
authors.lastname: Lewin
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D016175:B-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism; D015415:Biomarkers / Q000097:blood; D001772:Blood Cell Count; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D049109:Cell Proliferation; D002478:Cells, Cultured; D006413:Hematopoietic System / Q000254:growth & development* / Q000378:metabolism; D007107:Immune System / Q000254:growth & development* / Q000276:immunology / Q000378:metabolism; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008213:Lymphocyte Activation; D017208:Rats, Wistar; D013154:Spleen / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism; D013950:Thymus Gland / Q000254:growth & development / Q000276:immunology / Q000378:metabolism
chemical_list: D015415:Biomarkers; D007074:Immunoglobulin G; D007075:Immunoglobulin M
keywords: Blood; Development; Hematopoietic system; Immune system; Juvenile animal study