title: Direct analysis of thymic function in children with Down's syndrome.
abstract: BACKGROUND
  Down's syndrome (DS) is characterized by several immunological defects, especially regarding T cell compartment. DS is considered the best example of accelerated ageing in humans. Direct observations of the thymus have shown that in DS this organ undergoes severe histological and morphological changes. However, no data on its capacity to generate T cells are present in the literature. Here, using a new technology based upon real time PCR, we have investigated the capacity of the thymus to produce and release newly generated T lymphocytes (the so called "recent thymic emigrants", RTE) in children with DS.
  
  
  METHODS
  We studied 8 children affected by DS, aged 2-7 years, compared with 8 age- and sex-matched healthy controls. Flow cytometry was used to determine different lymphocytes subsets. Real time PCR with the Taqman system was used to quantify the amount of RTE,i.e.peripheral blood lymphocytes that express the T cell receptor rearrangement excision circles (TREC).
  
  
  RESULTS
  In comparison with control children, those with DS had a significant lower number of TREC+ peripheral blood cells. Moreover, in DS children but not in controls, a strong negative correlation between age and the levels of TREC+ cells was found.
  
  
  CONCLUSIONS
  The direct measure of thymic output indicates that the impairment of the organ results in a reduced production of newly generated T cells. This observation could suggest that cytokines able to modulate thymic function, such as interleukins, could be useful to improve the functionality of the organ and to treat the immunodeficiency present in DS subjects.
authors.affiliation: Dipartimento di Biopatologia e Metodologie Biomediche, Università di Palermo, via Tukory 211, 90134 Palermo, Italy.
authors.forename: Nicole
authors.initials: N
authors.lastname: Prada
authors.affiliation: Cattedra di Immunologia, Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, via Campi 287, 41100 Modena, Italy.
authors.forename: Milena
authors.initials: M
authors.lastname: Nasi
authors.affiliation: Cattedra di Immunologia, Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, via Campi 287, 41100 Modena, Italy.
authors.forename: Leonarda
authors.initials: L
authors.lastname: Troiano
authors.affiliation: Cattedra di Immunologia, Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, via Campi 287, 41100 Modena, Italy.
authors.forename: Erika
authors.initials: E
authors.lastname: Roat
authors.affiliation: Cattedra di Immunologia, Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, via Campi 287, 41100 Modena, Italy.
authors.forename: Marcello
authors.initials: M
authors.lastname: Pinti
authors.affiliation: Cattedra di Immunologia, Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, via Campi 287, 41100 Modena, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Nemes
authors.affiliation: Cattedra di Immunologia, Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, via Campi 287, 41100 Modena, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Lugli
authors.affiliation: Cattedra di Immunologia, Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, via Campi 287, 41100 Modena, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Ferraresi
authors.affiliation: Clinica Odontoiatrica, Università di Modena e Reggio Emilia, via del Pozzo 71, 41100 Modena, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Ciacci
authors.affiliation: Clinica Odontoiatrica, Università di Modena e Reggio Emilia, via del Pozzo 71, 41100 Modena, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Bertoni
authors.affiliation: Servizio di Neuropsichiatria Infantile, AUSL Modena, via Cardarelli 45, 41100 Modena, Italy.
authors.forename: Ornella
authors.initials: O
authors.lastname: Biagioni
authors.affiliation: Servizio di Neuropsichiatria Infantile, AUSL Modena, via Cardarelli 45, 41100 Modena, Italy.
authors.forename: Milena
authors.initials: M
authors.lastname: Gibertoni
authors.affiliation: Servizio di Neuropsichiatria Infantile, AUSL Modena, via Cardarelli 45, 41100 Modena, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Cornia
authors.affiliation: Servizio di Neuropsichiatria Infantile, AUSL Modena, via Cardarelli 45, 41100 Modena, Italy.
authors.forename: Liviana
authors.initials: L
authors.lastname: Meschiari
authors.affiliation: Servizio di Neuropsichiatria Infantile, AUSL Modena, via Cardarelli 45, 41100 Modena, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Gramazio
authors.affiliation: Servizio di Neuropsichiatria Infantile, AUSL Modena, via Cardarelli 45, 41100 Modena, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Mariotti
authors.affiliation: Clinica Odontoiatrica, Università di Modena e Reggio Emilia, via del Pozzo 71, 41100 Modena, Italy.
authors.forename: Ugo
authors.initials: U
authors.lastname: Consolo
authors.affiliation: Clinica Pediatrica, Università di Modena e Reggio Emilia, via del Pozzo 71, 41100 Modena, Italy.
authors.forename: Fiorella
authors.initials: F
authors.lastname: Balli
authors.affiliation: Cattedra di Immunologia, Dipartimento di Scienze Biomediche, Università di Modena e Reggio Emilia, via Campi 287, 41100 Modena, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Cossarizza
references.citation: Nature. 1998 Dec 17;396(6712):690-5
references.pmid: 9872319
references.citation: Am J Med Genet Suppl. 1990;7:213-8
references.pmid: 2149950
references.citation: J Immunol. 1981 Jun;126(6):2161-4
references.pmid: 6453157
references.citation: Immunol Invest. 1987 Aug;16(5):371-82
references.pmid: 2961683
references.citation: Immunol Today. 1995 Jan;16(1):12-6
references.pmid: 7880382
references.citation: Adv Exp Med Biol. 2002;512:81-90
references.pmid: 12405190
references.citation: Clin Immunol Immunopathol. 1988 Nov;49(2):175-86
references.pmid: 2971489
references.citation: Immunol Lett. 1990 May;24(2):137-40
references.pmid: 2141323
references.citation: Curr HIV Res. 2004 Apr;2(2):177-83
references.pmid: 15078181
references.citation: Blood. 2000 May 1;95(9):2860-8
references.pmid: 10779432
references.citation: Ann N Y Acad Sci. 1991;621:428-40
references.pmid: 1830464
references.citation: Blood. 2003 Dec 15;102(13):4600-7
references.pmid: 12933579
references.citation: AIDS. 2002 May 24;16(8):1181-3
references.pmid: 12004278
references.citation: AIDS. 2002 Aug 16;16(12 ):1609-16
references.pmid: 12172082
references.citation: Clin Immunol. 2000 Apr;95(1 Pt 1):62-9
references.pmid: 10794433
references.citation: Thymus. 1989;14(1-3):163-70
references.pmid: 2533759
references.citation: J Acquir Immune Defic Syndr. 2004 Mar 1;35(3):213-22
references.pmid: 15076235
references.citation: Blood. 1991 Mar 15;77(6):1263-70
references.pmid: 1825795
references.citation: Lancet. 1984 May 5;1(8384):983-6
references.pmid: 6143966
references.citation: J Immunol. 1992 Oct 1;149(7):2506-12
references.pmid: 1388194
references.citation: Adv Exp Med Biol. 1990;264:499-502
references.pmid: 2173880
references.citation: Blood. 2002 May 1;99(9):3449-53
references.pmid: 11964316
references.citation: Clin Immunol Immunopathol. 1996 Mar;78(3):209-14
references.pmid: 8605695
references.citation: Bratisl Lek Listy. 1997 Apr;98(4):221-8
references.pmid: 9264831
references.citation: J Clin Immunol. 2000 Jul;20(4):250-6
references.pmid: 10939712