CD8 T

Treg exert differential effects on the proliferation and differentiation of CD8 T cell subsets in chronic HIV-1 infection M. Nikolova1, M. Muhtarova1, M. Younas2, J.D. Lelievre2,3, H. Taskov1, Y. Levy2,3 1National

Center of Infectious and Parasitic Diseases, Sofia, Bulgaria Paris Est Créteil, Inserm U955, Créteil, France 3Henri Mondor Hospital, APHP, Créteil, France

2Université

XVIII International AIDS Conference | July 18-23 2010 | Vienna, Austria

CD8 T cell differentiation and functional maturation Differentiation IFNg

Cytotoxicity

Proliferation

Naïve Central memory CD45RA+ CCR7+

CD28+ CD27+

Effector

Memory Effector memory 1

Effector memory 2

CD45RA-/CD45RO+

Effector

Terminal effector CD45RA+

Background & Rationale 

CD8 T memory/effector subset balance determines the control of chronic viral infections



HIV infection is characterized by a decreased proliferative capacity of CM CD8 T cells and incomplete differentiation of HIV-specific effector T cells (Appay V. et al, J. Exp. Med 2000;

Champagne P. et al, Nature 2001)



We have previously shown that Treg (CD4+CD25highFoxP3+) influence M/E CD8 subset balance in HIV- donors: Treg inhibit the proliferation of effectors and the differentiation of memory CD8 T upon polyclonal and antigen-specific in vitro stimulation

(Nikolova M. et al, Blood, 2009) 

Treg are expanded in acute and chronic HIV-1 infection, and inhibit effector CD8 T cell responses in vitro (Weiss L. et al,

Blood 2004; Kinter A. et al, J. Exp. Med 2004)

HYPOTHESIS AND OBJECTIVE

We hypothesized that the expansion of Treg in HIVinfected patients might contribute to the dysbalance between effector and memory CD8 T cells

Our objective was to investigate the effects of Treg on the proliferation and maturation of different CD8 T cell subsets in chronic HIV-1 infection

STUDY POPULATION HIV-1+cART+ subjects (n=14), CD4 >350 cells/ml, VL < 50 HIV RNA copies/ml

STUDY DESIGN PMNC

D0, flow cytometry

(CD45RA/CCR7/CD27/CD28/CD3/CD8) Treg depletion, anti-CD25 DynaBeads

proportions of CD8 T subsets

PMNC,Treg-

PMNC, Treg+

CFSE staining, polyclonal stimulation: immobilized anti-CD3 (5 mg/ml)

D5, flow cytometry

(CFSE/CD45RA/CCR7/CD27/CD28/CD3/CD8)

COMPARISON proportions and proliferation rates of CD8 T subsets

CD8 T SUBSETS PHENOTYPING : GATING STRATEGY

CD8 T CELL SUBSETS: PROLIFERATION RATES

Gated CD3+CD8+ Ly

Gated CD8 T subset Treg+

Treg-

N

E

M

CFSElow 81%

CFSElow 68 %

CD45RA

TE

CD27 1. CD27+CD45RA+ Naïve, N 2. CD27+CD45RA- Memory, M 3. CD27- CD45RA- Effector, E 4. CD27- CD45RA+ Terminal Effector, TE

CFSE

CFSE-stained Treg+ and Treg- PMNC were stimulated with 5mg/ml immobilised anti-CD3 % CFSElow cells was determined on D5

Polyclonal stimulation in the presence of Treg results in a decreased rate of CD8 T cell proliferation ** 100

% CFSElow CD8 T

90

80

70

60

50

40

Treg+ Treg+ CD8

TregTregCD8

Proliferation rates of Treg+ and Treg- CD8 T (n=14, D5 anti-CD3), mean 72 vs. 81 % CFSElow CD8 T ** p