title: Cellular immunity before and after leptin replacement therapy.
abstract: BACKGROUND
  The few identified leptin-deficient children have immune deficiency.
  
  
  OBJECTIVE
  To evaluate whether a newly-identified leptin-deficient boy has immune defects; to assess the immune changes during leptin replacement.
  
  
  METHODS
  A 5 year-old boy with congenital leptin deficiency was evaluated before, 2 weeks and 6 weeks after the initiation of recombinant methionyl human leptin. Thymic volume was measured by computed tomography. Humoral immunity was assessed by measuring levels of several immunoglobulins. Cellular immunity was evaluated by the analysis of lymphocyte proliferation in response to mitogens. Lymphocyte subsets were quantified by flow cytometry.
  
  
  RESULTS
  At baseline, thymic volume was increased. The lymphocyte subsets count and humoral/cellular immunities were normal. After treatment, proliferative response to mitogens increased by 1.5- to 3-fold, and lymphocyte count decreased by 17%.
  
  
  CONCLUSIONS
  Immune defects are not an obligatory feature of congenital leptin deficiency. Even in the absence of significant immune defects, leptin replacement therapy enhanced T-cell responsiveness.
authors.affiliation: John Curtin School of Medical Research, Australian National University, Canberra, Australia.
authors.forename: Gilberto Jorge
authors.initials: GJ
authors.lastname: Paz-Filho
authors.forename: Tuncay
authors.initials: T
authors.lastname: Delibasi
authors.forename: Halil Kutlu
authors.initials: HK
authors.lastname: Erol
authors.forename: Ma-Li
authors.initials: ML
authors.lastname: Wong
authors.forename: Julio
authors.initials: J
authors.lastname: Licinio
mesh_terms: D002675:Child, Preschool; D005434:Flow Cytometry; D020249:Hormone Replacement Therapy; D006801:Humans; D007111:Immunity, Cellular / Q000502:physiology*; D056724:Immunity, Humoral / Q000502:physiology; D007136:Immunoglobulins / Q000097:blood; D020738:Leptin / Q000008:administration & dosage* / Q000172:deficiency*; D008213:Lymphocyte Activation / Q000187:drug effects; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets; D008297:Male; D020125:Mutation, Missense; D011994:Recombinant Proteins / Q000008:administration & dosage; D013601:T-Lymphocytes / Q000276:immunology; D013950:Thymus Gland / Q000000981:diagnostic imaging / Q000473:pathology; D014057:Tomography, X-Ray Computed
chemical_list: D007136:Immunoglobulins; D020738:Leptin; D011994:Recombinant Proteins