Effacing of the T cell compartment by cardiac transplantation in infancy.
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.
Ogle
Brenda M
BM
Transplantation Biology Program, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
West
Lori J
LJ
Driscoll
David J
DJ
Strome
Scott E
SE
Razonable
Raymund R
RR
Paya
Carlos V
CV
Cascalho
Marilia
M
Platt
Jeffrey L
JL
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