title: Age-related changes in human thymus.
abstract: Thymic biopsies obtained during open heart surgery were examined for age-related involution of the parenchyma and changes in cell surface characteristics. In parallel with the parenchymal atrophy, E-rosette-forming cells continuously decreased with age and were progressively replaced by an increasing proportion of 'null' lymphoid cells. These changes appeared to be independent of each other. The significance of these findings in the context of the host's immune mechanism is discussed.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D008214:Lymphocytes / Q000145:classification / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012397:Rosette Formation; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology*