hiv-1 immunopathogenesis: innate immunity luis j. montaner ... · hiv-1 immunopathogenesis: innate...

HIV-1 Immunopathogenesis: Innate Immunity

Luis J. Montaner, D.V.M., M.Sc., D.Phil.

1The screen versions of these slides have full details of copyright and acknowledgements


1

Luis J. Montaner, D.V.M., M.Sc., D.Phil.Professor, The Wistar Institute

HIV-1 Immunopathogenesis Laboratory

Lecture acknowledgementsAcknowledgement for data/slide contributions:

• Danny Douek, NIH Vaccine Center

• G. Trinchieri, NCI, NIH

• Ashle Haase, University of Minnesota

2

• Beatrice Hahn, University of Alabama

• Jim Hoxie, University of Pennsylvania

• Michael Lederman, Case Western University

• Guido Silvestri, University of Pennsylvania

• Costin Tomescu, The Wistar Institute

• Jenna Lee, The Wistar Institute

• Section I: – Introduction to HIV-1 disease

Lecture outline

3

• Section II: – Innate effectors (DC, NK, macrophage)– Innate response in HIV-1 infection:

immune activation hypothesis




• Viral life cycle

Section I

4

• Acute infection

• Stages of immunopathogenesis

1. Target cells: – CD4 T cells monocyte/macrophages– DC subsets

2. Molecules needed for infection:– CD4, CCR5/CXCR4

Global review: viral life cycle

5

– Annexin II/CD63 (monocytes)3. Post-fusion: determinants for infection

– Intrinsic factors of resistance (e.g., APOBEC)

– Intracellular host factors needed for infection (e.g, emerin, transcriptional factors)

Source: J. Hoxie

Global review: acute infection (1)Viral transmission: favors high viral load, viral “dose”,

and results in preferential selection for CCR5 HIV-1

Recipient

A

B

Donor

6Source: J. Hoxie

C

E

F

G

D




D3+

T c

ells

)

SIV- 1 dpiGlobal review: acute infection (2)

123+

pD

Cs)

SIV- 2h pi

7

Endo

cerv

ix (C

D

4 dpi 6 dpi

Source: A. Haase

Endo

cerv

ix (C

D

1 dpi 21 dpi

Global review: acute infection (3)

8

Mechanism create generally favorable environment for expansion of small founder populations of infected cells

pDCs chemokines

CCR5 “f l”

Mucosal outside-in signalingGlobal review: acute infection (4)

9

Expand small founder populationsInfected cells

Establish systemic infection

CCR5+ “fuel”

Source: A. Haase





10Day 4 Day 17

Simian immunodeficiency virusSource: J. Hoxie

HIV+HIV+HIV-HIV-Global review: acute infection (6)

Gut

CD

4%

70080090010001100

mm

3

11

J Exp. Med. 2004; 200: 749

0100200300400500600700

CD

4+/m

Weeks 0 3 6 9 12 1

GALT CD4(+) T cell depletion during acute pathogenic

How important is the GALT depletion to disease outcome?

Recent advance: acute infection

12

HIV and SIV infections of humans and Rh is necessary but neither sufficient nor predictive of disease progression, with levels of immune activation, proliferation and apoptosis being key factors involved in determining progression to AIDS





Why a drop?

70080090010001100

mm

3

Gut

CD

4%

13Weeks 0 3 6 9 12 1

0100200300400500600700

CD

4+/m


14Source: J. Hoxie

Viral "set point" as a predictor of disease


15




Primary infection

Acute HIV syndromeWide dissemination of virusSeeding of lymphoid organs

500

600

700

800

900

1000

1100

D4+

/mm

3

Clinical latency

oad/

vira

l tite

r

Opportunisticinfections

Death

16

0 3 6 9 12 1 2 3 4 5 6 7 8 9 10 110

100

200

300

400

500

Weeks Years

CD

Immunosuppression

Immune activation

Vira

l lo

Acute Infection Survival/escape

Immune response: timeline to effectors

17Source: G. Trinchieri

Monocyte/macrophage

18

Monocyte/macrophage




Immunopathogenesis of HIV-1 disease (1)

19

Macrophages & HIV-1 infection• Cellular targets of HIV-1• Reservoirs of HIV-1• HIV-1 impairs monocyte/macrophage functions

– Phagocytosis, chemotaxis, intracellular killing, inflammatory responses and antigen presentation are impaired

HIV accessory protein Some macrophage functions modulated

20

y p p g

tat Upregulates chemokines, CCR5, CXCR4, TRAIL,downregulates MR, Induces TNF?, IL1?, IL6

vpr Downregulates IL12p35, Induces IL10, IL6, IL8, interacts with SP1, p53 and GR pathway

vif Inhibits Src Kinase, Hck, promotes virus integration

vpu Promotes CD4 degradation and virus release

nef Activates NFkB, Stat1/3, AP-1, induces chemokines,promotes CD4 degradation

HIV-1 and monocyte apoptosisMonocyte and virus survival

Monocyte and virus death

21

• Resist cytopathic effects of prolonged HIV infection in vitro– Curr Top Microbiol Immunol. 1992; 181: 239-63. Review

– Curr HIV Res. 2003 Jul; 1(3): 261-74. Review

• Viral accessory proteins upregulate anti-apoptotic pathways

– Nef upregulates Bcl-xl in TF macrophage cell line (J Biol Chem. 2004 Dec 3; 279(49): 51688-96. Epub 2004 Sep 30)

– Tat upregulates Bcl-2(J Biomed Sci. 2002 Mar-Apr; 9(2): 133-9)




Human DC subsets

22

Human DC subsets

Model of DC migration and maturation

Skin venule

Precursor DC

Skin

Langerhans cell(immature DC)

Ag

Afferent lymph

23

Bone marrow

DC progenitor Draining lymph node

Mature DC

Ag-specific T cells

HEV

MHC I antigen presentation

24Yewdell (2003) NRI 3: 952




Antigen presentationMHC I MHC IICross presentation

25Heath (2002) NRI 1:126

Precursors

Immature DC

Proposed pathways of human DC development

26Adapted from Shortman (2002) NRI 2: 151

Mature DC

Myeloid DC

Plasmacytoid DC

Characteristics of human DCCirculating precursor DC in human peripheral blood

27Adapted from Shortman (2002) NRI 2: 151





28

Myeloid dendritic cell (MDC) Plasmacytoid dendritic cell (PDC)HLA- DR+++ HLA-DR+++CD11c+ CD 123+CD45RO+ CD45RA+ FCR (R1, CD32, CD64)CD4+/- CD4+CD33+BDCA-1+ (CD1c) BDCA2+/4DC-SIGN+ DC-SIGN+

Dendritic cell subsets

29

DC-SIGN+ DC-SIGN+

IL-12 ++ IFN-α+++

PDC: Lin- CD11c- CD123+ MHC IIhiMDC: Lin- CD11chi CD123- MHC IIhi

A.

HIV-

HIV+

B.

HIV-

HIV+

Human DC subsetsA.

HIV-

A.

HIV-

HIV+

30

HIV+ HIV+

Myeloid DC = Lin- CD11chi CD123- MHC IIhi

Plasmacytoid DC = Lin- CD11c- CD123+ MHC IIhi




Human DC: C type lectins

31

Human DC: C-type lectins

2 types of C-type lectins expressed on DC

32Figdor (2002) NRI 2: 77

Pathogens that bind DC-SIGN

33van Kooyk (2003) NRI 3: 697




Natural killer cells

34

Natural killer cells

CD8+ (cytotoxic) T cell recognition of target cells

Fas-FasL

35

Perforin/granzyme

MHC-ITCR

Natural killer cell recognition of target cells (1)

36

MHC-IKIR

NCR




Fas-FasLINF-γ


37

MHC-IKIR

NCR

Perforin/granzyme

MICAIL-2

IL-12

IL-15

IL-18

INF-α

MHC class-I locus

HLA-A HLA-B HLA-C HLA-E HLA-G MICA, B

KIR2DL1/2 LIR1/ILT2NKG2A

KIR3DL2LIR1/ILT2

LIR1/ILT2KIR3DL1LIR1/ILT2

NKG2DCD160


38

NKG2ALIR1/ILT2 LIR1/ILT2

NKp30 HCMV pp65, heparin sulfate

NKp44 Viral haemagglutinin, HIV-1 gp41

NKp46 Viral haemagglutinin, Heparin Sulfate

KIR3DS1KIR3DS2CD160


39




• HLA B*5701 is highly associated with restriction of virus replication in a subgroup of HIV-infected long term nonprogressorsPNAS. 2000, 14: 97(6):2709-14

• Progression of HIV to AIDS: a protective role for HLA-B27AIDS Rev. 2004, 6: (2):89-96

Role of HLA and KIR alleles in rate of progression to AIDS

40

• Epistatic interaction between KIR3DS1 and HLA-B delays the progression to AIDSNature Genetics. 2002, 31: 429

• Increased proportion of KIR3DS1 homozygotes in HIV-exposed uninfected individualsAIDS. 2008, 12: 22(5):595-9

• Increased NK activity in HIV-1 exposed but uninfected Vietnamese intra-venous drug usersJournal of Immunology. 2003, 171: 5663

• Impairment appears in early stages, before the onset of CD4+ T cell depletion

• Characterized by loss of:

– Cytotoxicity

Prod ction of IFN

NK cells & HIV-1 infectionImpaired NK cell function in HIV-infected patients

41

– Production of IFN-γ

– Response to IFN-α (progression indicator)

– Decrease in mature NK subsets

• Progressive reduction of NK cell number (in association with generalizedhematopoietic failure) at late stage disease (AIDS)

• The pathogenic mechanisms of NK cell inactivation is unknown

• Limited reports postulate mature NK cells are infected by HIV-1

NK balancing act:

+/- NK cell differentiation state

+/- Killing activating interactions (ex., NCR, Ab)

+/- Killing inhibitory interactions (ex., MHC-I)

To kill or not to kill?

42

/ Killing inhibitory interactions (ex., MHC I)

+/- Dendritic cell help (ex., type-1 IFN)

+/- T-cell activation state (ex., IL-2)

+/- NK functional/activation state

+ Kill- Not Kill




Measuring recovery following immune reconstitution

43

following immune reconstitution and HIV-1 therapy

Understand the impact of steady-state HIV-1 replication on the innate effector compartment based on the study of HIV-1 infected persons off antiretroviral therapy

ART & innate reconstitution

44

Determine the degree of immune reconstitution of innate effector cell function following antiretroviral therapy

AIDS; 2007 Jan 30; 21(3): 293-305J Immunol; 2007 Aug 15; 179(4): 2642-50 J Immunol; 2007 Aug 15; 179(4): 2097-104

• ART-naïve HIV-infected patients initiating ART (NRTI backbone + NNRTI or PI)

• Controls: non HIV-infected donors• Both genders, >18 y.o

RO1 AI51225 - prospective study:Philadelphia FIGHT cohort

45

Variable time, visits every

4 weeks

Supp

ress

ion

= 0

wks

4 w

ks

8 w

ks

16 w

ks

32 w

ks

52 w

ks

Bas

elin

e

HIV RNA




<0.0001

0.0001

0.0125

BL VS 52 Controls0

500

1000

1500

2000

2500

3000

3500

4000

0.0245

Influenza PR8

BL VS 52 C t l0

500

1000

1500

2000

2500

3000

3500

<0.0001

0.0002

0.013

0.0001

0.0134

CpG-2216

pg/m

l IFN

-α

pg/m

l IFN

-α

46

BL VS 52 Controls BL VS 52 Controls

CD123 Per-CP

Intracellular IFN-α production

HIV-1 Viremic at BL <50 copies/ml at week 52 Control HIV-

Reconstitution of PDC & NK cytotoxicity

NK antiviral function directly

<0.0001*

BL VS 52 Controls0

5001000150020002500300035004000450050005500

0.0006***

<0.0001**

47

related to level of plasmacytoid dendritic cell recovery of function

Indu

ced

IFN

-αW

k 52

0

250

500

750

1000

1250

1500

0 1000 2000 3000 4000 5000 6000

r= 0.66p = 0.003

AUC (NK cytotoxic activity)

BL VS 52 Controls

Summary model of immune reconstitution time-line

48




Conclusion

• Innate compartment is recovered after a period >32 weeks of viral suppression; Evidence for a negative effect of HIV-1 on PDC frequency and function

49

• Not all immune reconstitution is the same after a year of HIV-1 suppression is achieved

• Evidence for a predetermined potential for innate recovery leading to heterogeneity in immune reconstitution

Does the innate immune activation response

Section II

50

determine HIV-1 disease?

Only a small proportion of CD4 cell loss variability (4%-6%)

Recent paradigm shift:viral load & CD4 loss

51

could be explained by presenting plasma HIV RNA level

Rodriguez et al., Predictive value of plasma HIV RNA level on rate of CD4 T-cell decline in untreated HIV infection; JAMA. 2006 Sep 27; 296(12): 1498-506




Immune activation & disease progression

Evidence #1:Immune activation (though related to VL) predicts HIV disease progression risk independently

– CD38 expression a better predictor of disease progression than VL (Liu JAIDS ’98 Giorgi JID ’99 Deeks ’04 Wilson ‘04)

52

(Liu JAIDS 98, Giorgi JID 99, Deeks 04, Wilson 04)

– Pre-seroconversion, CD70 expression predicts disease progression risk (Hazenberg AIDS ’04)

Slide courtesy of M. Lederman

HIV-2

SIVmac

Natural SIV hosts are the origin of HIV-1, HIV-2, and SIVmac

Sooty mangabey

SIVsyk

Sykes monkey

SIVcol SIV

SIVsmm

G t

Evidence #2

53

HIV-1Chimpanzee

SIVcpz

SIV

SIVcol

Mantled guereza

L’Hoest’s monkey Mandrill

SIVlho

SIVrcm

SIVgsn

SIVmnd

Red-capped mangabey

SIVver

Vervet monkey

Greater spot-nosed

monkey

Slide courtesy of Beatrice Hahn

Sooty Mangabey

Natural host (SIV smm)– High level viremia– CD4 depletion extremely rare– No OIs– Low level immune activation

54

Rhesus HIV-1 model (if given SIV smm)

– High level viremia– Circulating CD4 depletion – OI risk and death– High level immune activation

Slide courtesy of M. Lederman




Mandl et al Divergent TLR7 and TLR9 signaling and type I interferon

Key reference: evidence for TLR activation and immunopathogenesis (1)

55

Mandl et al., Divergent TLR7 and TLR9 signaling and type I interferon production distinguish pathogenic and nonpathogenic AIDS virus infections; Nat Med. 2008 Oct; 14(10):1077-87

HIV-1 Nef associated with HIV-1 activation events

Evidence #3

56Schindler et al. Nef-Mediated suppression of T cell activation was lost in a lentiviral lineage that gave rise to HIV-1. Cell, 125: 1055-1067,2006

Evidence # 4: plasma LPS levels are increased in chronic HIV infection

57Brenchley et al., Nat Med 06




Human Toll-Like Receptors (TLRs)

58Kanzler et al., Nat Med ‘07

Evidence #5: HIV RNAs can activate T cells indirectly via TLR 7, 8

59CD69

CD

8

Evidence #6: CD4 T cells activated to enter cell cycle by microbial TLR ligands

do not complete division but instead die by apoptosis

60Data and slide courtesy of M. Lederman




Key reference: evidence for TLR activation and immunopathogenesis (2)

61

Funderburg et al., Toll-like receptor ligands induce human T cell activation and death, a model for HIV pathogenesis. PLoS ONE. 2008 Apr 2; 3(4): e1915

Evidence #7:

– Loss of CD4 in natural SIV host with virus yet without activation does not lead to diseaseMilush et al., Virally induced CD4+ T cell depletion is not sufficient to induce AIDS in a natural host J Immunol 2007 Sep 1;179: 3047-56

Recent advance: immune activation hypothesis

62

AIDS in a natural host. J Immunol. 2007 Sep 1;179: 3047 56

– Viral replication without CD4 activation or loss of function associates with slow disease progressionChoudhary et al., Low immune activation despite high levels of pathogenic human immunodeficiency virus type 1 results in long-term asymptomatic disease; J Virol. 2007 Aug; 81: 8838-42

Disease model: it’s the interaction!

63J Exp Med. 2007 Sep 3; 204(9): 2171-85




HIV

Gut

CD4 depletionenteropathy

Tissues

64

HIV

Immune activation

Slide courtesy of D. Douek

Tcm

Tcm

TemTem

TemTem

AIDS

Major hypothesis

Innate cell function is a dominant feature of immune health,

65

disease progression, and adaptive immune control in chronic

HIV-1 infection and AIDS pathogenesis

66Thank you!




67

hiv-1 immunopathogenesis: innate immunity luis j. montaner ... · hiv-1 immunopathogenesis: innate...

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