title: Effacing of the T cell compartment by cardiac transplantation in infancy.
abstract: For cardiac transplantation in infants, T cells are depleted and the thymus is removed. These manipulations should cause profound defects in the T cell compartment. To test this concept, 20 subjects who underwent cardiac transplantation in infancy and healthy age-matched subjects were studied. The number of T cells in the blood was nearly normal in all subjects 1-10 years after surgery. However, newly generated T cells were undetectable in 10 recipients and 10-fold less than controls in 10, suggesting absence of thymic function. TCRbeta chain diversity, measured by a novel technique, was approximately 100-fold lower than controls. T cell function, deduced from levels of human herpesvirus 7 and response to hepatitis B immunization, were notably impaired. Yet cardiac transplant recipients were generally free of opportunistic infections. Our findings demonstrate a novel approach to measuring lymphocyte diversity and suggest that understanding how these subjects resist infection could yield important insights into immune fitness.
authors.affiliation: Transplantation Biology Program, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
authors.forename: Brenda M
authors.initials: BM
authors.lastname: Ogle
authors.forename: Lori J
authors.initials: LJ
authors.lastname: West
authors.forename: David J
authors.initials: DJ
authors.lastname: Driscoll
authors.forename: Scott E
authors.initials: SE
authors.lastname: Strome
authors.forename: Raymund R
authors.initials: RR
authors.lastname: Razonable
authors.forename: Carlos V
authors.initials: CV
authors.lastname: Paya
authors.forename: Marilia
authors.initials: M
authors.lastname: Cascalho
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Platt
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D005434:Flow Cytometry; D016027:Heart Transplantation / Q000276:immunology* / Q000473:pathology; D006801:Humans; D007111:Immunity, Cellular; D007223:Infant; D018655:Lymphocyte Count; D008212:Lymphocyte Depletion; D008297:Male; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D013934:Thymectomy; D013950:Thymus Gland / Q000166:cytology* / Q000276:immunology* / Q000601:surgery