CD4+ memory stem cells (T SCM ) in pathogenic and non-pathogenic SIV infections

1. CD4+ memory stem cells (TSCM) inpathogenic and non-pathogenic SIV infections Guido Silvestri, MD Yerkes National Primate Research Center Emory University School of Medicine Emory Center for AIDS Research (CFAR) Emory Vaccine Center

2. The pattern of Infected CD4+ T Cell is a key determinant of AIDS pathogenesis Loss of CD4 T cell homeostasis/CD4 depletion Damage to LN architecture & lymphoid niche Features & efficacy of host immune responses Pattern of in vivo infected cells Size and dynamics of the “latent” reservoir Chronic immune activation Picker . J Exp Med 2007; Letvin et al. Science 2007; Roederer et al. J Exp Med 2007; Brenchley et al. Immunity 2010;Chomont et al., Nat Med 2009; Paiardiniet al. Nat Med 2011; Brenchley et al. Blood 2012;Autran et al., ClinInfDis 2012; Chahroudiet al., Science 2012; Saez-Cirion et al. PLoS Path 2013

3. Comparative AIDS Research SM RM HIV AIDS NO YES YES Blood CD4 depletion Rare YES YES Viral Load HIGH HIGH HIGH Preserved gut & LN integrityYES NO NO Microbial translocation NOYESYES Chronic immune activation NO YES YES

4. Restricted infection of CD4+ TCMcells in SIV-infected sooty mangabeys Level of infected cells in vivo Level of infected cells following in vitro infection Paiardini et al, Nat Med 2011

5. Higher levels of Tfh infection in SIV-infected RMs and HIV-infected humans than SIV-infected SMs LN anatomic distribution of productively infected cells in RMs, humans, and SMs. (A) SIV/HIV vRNA+ cells/mm2 in LNs of chronically infected RMs, humans, and SMs. (B) SIV/HIV vRNA+ in B-cell follicles (C) Percentage of LN area that consists of B-cell follicles. Brenchleyet al,Blood 2012

6. How HIV and SIV infection cause AIDS: Lessons from natural SIV infections Chronic, generalized Immune Activation Virus replication in central memory CD4+ T cells Progressive Infection and AIDS

7. Complexity of the memory CD4+ T cell pool antigen Proliferation and clonalexpansion in response to antigenic stimulation Naïve Cell Effector(short-lived, activated) Contraction phase Memory cell pool Memory stem cell Central Memory:Resident in LNs, spleen. Able to self-renew and differentiate into Tem. CD62L+ CCR7+ Effector Memory: Resident in periphery. Able to respond quickly to re-exposure. CD62L- CCR7-

8. What is a T memory stem cell (Tscm)? • 1-3% of circulating and LN-based CD4+ and CD8+ T cells. • Identified by classical naïve T cell markers (CD45R+CD45RO-CD62L+CCR7+CD127+CD27+CD28+), but also CD95 & CD122. • Express more LFA-1 and CXCR3 than naïve cells, but less than TCM (and less Bcl-2 than naïve cells but more than TCM). • Least differentiated memory subset, with high proliferative potential, and capable of self-renewal. • Multipotent: able to generate both TCM and TEM Gattinoni et al., Nat Med 2009; Turtle et al., Immunity 2009; Muranski et al., Immunity 2011; Gattinoni et al., Nat Med 2011; Luckey CJ, Weaver CT. Cell Stem Cell, 2012; Roederer et al., J Clin Invest, 2012

9. C. Identification of CD4+TSCM in healthy rhesus macaques and sooty mangabeys. A. D. FSC-H SSC-A Dead/14/16/20 FSC-A FSC-A CD3 E. CCR7 CD27 CD8 TSCM B. CD45RA CD28 CD4 CD95 CD122

10. C. Identification of CD4+TSCM in healthy rhesus macaques and sooty mangabeys. A. D. E. B. F.

11. CD4+ TSCM express levels of CXCR3 and CD11a similar to other memory CD4+ T cells subsets, and levels of Bcl-2 that are intermediate between naïve and TCM. B. C.

12. Higher levels of CCR5 expression on CD4+TSCM of healthy RMs as compared to SMs. C. A. D. E. B. F. RM CD4 SM CCR5

13. Selective preservation of CD4+TSCM cells during pathogenic SIV infection of RMs A. B. D. p= n.s. p= n.s.

14. A. SIV infection of RMs is associated with a significant depletion of CCR5+CD4+TSCM. B. C.

15. SIV infection of RMs is associated with increased proliferation of CD4+TSCM that significantly inversely correlates with the levels of CD4+TCM A. B. C. D.

16. Dynamics of CD4+TSCM during non-pathogenic infection of SM A. B. C. D.

17. Robust levels of CD4+TSCM infection in vivo are observed in SIV-infected RMs but not in SIV-infected SMs

18. CD4+ T memory stem cells in pathogenic and non-pathogenic SIV infections • CD4+ TSCM are numerically preserved during BOTH pathogenic and nonpathogenic SIV infections. • However, SIV-infected RM show (i) a selective depletion of CD4+CCR5+ TSCM; and (ii) higher levels of CD4+ TSCM proliferation that correlate significantly with the level of CD4+ TCM depletion. • Robust levels of direct virus infection of CD4+ TSCM are found only in SIV-infected RM, with 6 out of 7 SIV-infected SM showing no evidence of CD4+ TSCM infection.

19. CD4+ T memory stem cells in pathogenic and non-pathogenic SIV infections CCR5+ Ki67+ TSCM TCM RM AIDS SIV TSCM TCM TSCM TCM SM

20. Increasing contribution of Tscm to HIV reservoir over time (M. Lichterfeld) Lichterfeld, unpublished

21. Hypothesis: can reservoirs be eliminated when there is no virus in TSCM cells? ART TSCM TCMTEM TSCM TCMTEM Persistent TSCM (and TCM) reservoirs Absence of TSCM (and TCM) reservoirs

22. Acknowledgments Emory University/Yerkes MirkoPaiardini Colleen McGary Cynthia Derdeyn James Else Eric Hunter Vincent Marconi Ray Schinazi NIH/NIAID/NCI Jake Estes Jason Brenchley Daniel Douek Univ. of Pennsylvania Ron Collman Mike Betts Beatrice Hahn Univ. of Ulm Frank Kirchhoff Ragon Institute/HMS Mathias Lichterfeld Case Western Michael Lederman Institut Pasteur Michaela Muller-Trutwin University of Pittsburgh IvonaPandrea CristianApetrei Los Alamos National Labs Alan Perelson Supported by NIH/NIAID, Emory CFAR, Georgia Research Alliance Silvestri Lab Emily Cartwright VandyVanderford Steven Bosinger Ann Chahroudi AnkitaChowdhury Maud Mavigner KiranMir Tim Hayes Luca Micci TayebehHashempour Charlene Wang Alex Ortiz (NIH) Nichole Klatt (UW) Diane Carnathan Paul Carnathan SBRI -- Seattle Donald Sodora