title: Profound loss of intestinal Tregs in acutely SIV-infected neonatal macaques.
abstract: Impairment of the intestinal mucosal immune system is an early feature of HIV-infected children. Most infected children exhibit clinical gastrointestinal symptoms at some stage of infection, and persistent diarrhea is a marker for rapid disease progression. It is known that Tregs are especially important in mediating intestinal immune homeostasis and that loss of this subset may result in intestinal inflammation and associated clinical signs. Large numbers of FoxP3(+) T cells were found in all tissues in newborn macaques, which coexpressed high levels of CD25 and CD4, indicating that they were Tregs. Moreover, neonates had much greater percentages of Tregs in intestinal tissues compared with peripheral lymphoid tissues. After SIV infection, a significant loss of Tregs was detected in the intestine compared with age-matched normal infants. Finally, SIV-infected FoxP3(+) T cells were detected in tissues in neonates as early as 7 SIV dpi. These results demonstrate that Tregs constitute a significant fraction of CD4(+) T cells in neonatal intestinal tissues and that an early, profound loss of Tregs occurs in acute SIV infection, which may contribute to the intestinal disorders associated with neonatal HIV infection.
authors.affiliation: Divisions of *Comparative Pathology and Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana, USA rveazey@tulane.edu xwang@tulane.edu.
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Wang
authors.affiliation: Divisions of *Comparative Pathology and Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana, USA.
authors.forename: Huanbin
authors.initials: H
authors.lastname: Xu
authors.affiliation: Divisions of *Comparative Pathology and Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana, USA.
authors.forename: Chanjuan
authors.initials: C
authors.lastname: Shen
authors.affiliation: Divisions of *Comparative Pathology and Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana, USA.
authors.forename: Xavier
authors.initials: X
authors.lastname: Alvarez
authors.affiliation: Divisions of *Comparative Pathology and Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana, USA.
authors.forename: David
authors.initials: D
authors.lastname: Liu
authors.affiliation: Divisions of *Comparative Pathology and Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana, USA.
authors.forename: Bapi
authors.initials: B
authors.lastname: Pahar
authors.affiliation: Divisions of *Comparative Pathology and Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana, USA.
authors.forename: Marion S
authors.initials: MS
authors.lastname: Ratterree
authors.affiliation: Divisions of *Comparative Pathology and Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana, USA.
authors.forename: Lara A
authors.initials: LA
authors.lastname: Doyle-Meyers
authors.affiliation: Divisions of *Comparative Pathology and Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana, USA.
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Lackner
authors.affiliation: Divisions of *Comparative Pathology and Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana, USA rveazey@tulane.edu xwang@tulane.edu.
authors.forename: Ronald S
authors.initials: RS
authors.lastname: Veazey
mesh_terms: D000208:Acute Disease; D000818:Animals; D005260:Female; D015658:HIV Infections / Q000276:immunology / Q000473:pathology; D015497:HIV-1 / Q000276:immunology; D006801:Humans; D007410:Intestinal Diseases / Q000209:etiology / Q000276:immunology* / Q000473:pathology; D007422:Intestines / Q000276:immunology* / Q000473:pathology; D008253:Macaca mulatta; D008297:Male; D016097:Simian Acquired Immunodeficiency Syndrome / Q000150:complications / Q000276:immunology* / Q000473:pathology; D015302:Simian Immunodeficiency Virus / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000473:pathology
keywords: CD25; FoxP3; infant; intestine