title: Reduced IL-7R T Cell Expression and Increased Plasma sCD127 in Late Presenting HIV-Infected Individuals.
abstract: BACKGROUND
  Late presentation of HIV infection is associated with reduced chance of optimal immune recovery after initiating combination antiretroviral therapy (cART). Interleukin-7 (IL-7) and the corresponding receptor, IL-7 receptor (IL-7R) made up of CD127 and CD132, are crucial for T cell homeostasis. This study aimed to describe IL-7R and IL-7 before and after initiation of cART in late presenting HIV-infected individuals, and the impact on immune recovery and T cell subset distribution after initiation of cART.
  
  
  METHODS
  A total of 100 HIV-infected individuals initiating cART were included in a prospective study. Samples were collected at baseline and after 6, 12, and 24 months of cART. Proportion and expression {[median fluorescence intensity (MFI)]} of IL-7R on T cells, and plasma concentrations of soluble CD127 (sCD127) and IL-7 were determined.
  
  
  RESULTS
  The IL-7R expression was reduced in late presenters with CD4 cell count <200 cells per microliter compared with nonlate presenters and healthy controls as demonstrated by lower proportion of CD127 + CD132 + T cells and lower CD127 MFI. In contrast, plasma sCD127 was higher. These differences were partly reversed after suppressive cART. Interestingly, the CD127 MFI on CD4 T cells was found to be a predictor of increased thymic output after 24 months of suppressive cART.
  
  
  CONCLUSIONS
  Severely altered IL-7R expression was found in late presenters, and associations between IL-7R expression and thymic output after 24 months of suppressive cART indicate an impact of a IL-7 response for the long term de novo production from thymus.
authors: *Department of Infectious Diseases, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; †Viro-Immunology Research Unit; ‡Department of Clinical Immunology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark; and §Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.
authors: Hans J
authors: HJ
authors: Hartling
authors: Sofie
authors: S
authors: Jespersen
authors: Julie C
authors: JC
authors: Gaardbo
authors: Camilla
authors: C
authors: Sambleben
authors: Kristina
authors: K
authors: Thorsteinsson
authors: Jan
authors: J
authors: Gerstoft
authors: Henrik
authors: H
authors: Ullum
authors: Susanne D
authors: SD
authors: Nielsen
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000188:drug therapy / Q000473:pathology*; D006801:Humans; D015851:Interleukin-7 / Q000097:blood; D053699:Interleukin-7 Receptor alpha Subunit / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010949:Plasma / Q000737:chemistry*; D011446:Prospective Studies; D020395:Receptors, Interleukin-7 / Q000032:analysis*; D016176:T-Lymphocyte Subsets / Q000737:chemistry* / Q000276:immunology*
chemical_list: D019380:Anti-HIV Agents; C508605:IL7 protein, human; D015851:Interleukin-7; D053699:Interleukin-7 Receptor alpha Subunit; D020395:Receptors, Interleukin-7