Innate Immunity: The First Line Against Infections

Innate Immunity: Innate Immunity: The First Line Against InfectionsThe First Line Against Infections

Innate Immunity: Innate Immunity: The First Line Against InfectionsThe First Line Against Infections

Juan Pablo Horcajada. Juan Pablo Horcajada. Unidad de Enfermedades InfecciosasUnidad de Enfermedades InfecciosasHospital Universitario Marqués de ValdecillaHospital Universitario Marqués de ValdecillaSantander. Spain.Santander. Spain.

• In adults there are important differences inIn adults there are important differences in

– susceptibility to infectionssusceptibility to infections

– outcome of infections under treatmentoutcome of infections under treatment

• Innate immune system is the “third column” of the immun Innate immune system is the “third column” of the immun

system system

• There are new therapeutical possibilities There are new therapeutical possibilities

• In adults there are important differences inIn adults there are important differences in

– susceptibility to infectionssusceptibility to infections

– outcome of infections under treatmentoutcome of infections under treatment

• Innate immune system is the “third column” of the immun Innate immune system is the “third column” of the immun

system system

• There are new therapeutical possibilities There are new therapeutical possibilities

RelevanceRelevance

CellularCellularImmunityImmunity

Humoral Humoral InmunityInmunity

Innate immunityInnate immunity

• The innate immune systemThe innate immune system

• Mannose-binding lectinMannose-binding lectin

• MBL deficiency and infections: susceptibility and severityMBL deficiency and infections: susceptibility and severity

• Special populations: Special populations:

– Bone marrow transplant patientsBone marrow transplant patients

– HIV-infected patientsHIV-infected patients

• The innate immune systemThe innate immune system

• Mannose-binding lectinMannose-binding lectin

• MBL deficiency and infections: susceptibility and severityMBL deficiency and infections: susceptibility and severity

• Special populations: Special populations:

– Bone marrow transplant patientsBone marrow transplant patients

– HIV-infected patientsHIV-infected patients

IndexIndex

ImmunityImmunity

InnateInnate AdaptativeAdaptative

SpecificSpecificGenerates memoryGenerates memory

HumoralHumoralresponseresponse

CellularCellularresponseresponse

AntibodiesAntibodies LymphocytesLymphocytes

Non-specificNon-specificDoes not generate memoryDoes not generate memory

HumoralHumoralfactorsfactors CellsCells

External barriersExternal barriers

ComplementComplementAcute phase proteinsAcute phase proteins

NeutrophilsNeutrophilsMonocytesMonocytesNK CellsNK Cells

CLASSIC PATHWAYCLASSIC PATHWAYAg-Ab ComplexesAg-Ab Complexes

CLASSIC PATHWAYCLASSIC PATHWAYAg-Ab ComplexesAg-Ab Complexes

MBL-MASP1MBL-MASP1MBL-MASP1MBL-MASP1C3bC3bC3bC3b

C3C3C3C3

C1qC1qC1rC1rC1qC1qC1rC1r

C4C4C4C4 C2C2C2C2

C2aC2aC2aC2a

C3bC3bC3bC3bC3a, C5aC3a, C5aC3a, C5aC3a, C5a C5b-C9C5b-C9C5b-C9C5b-C9

Membrane attack complex, Membrane attack complex,

pathogen lysispathogen lysisMembrane attack complex, Membrane attack complex,

pathogen lysispathogen lysisInflamation, fagocyte Inflamation, fagocyte

recruitmentrecruitmentInflamation, fagocyte Inflamation, fagocyte

recruitmentrecruitmentOpsonization, eliminationOpsonization, elimination

of immunocomplexesof immunocomplexesOpsonization, eliminationOpsonization, elimination

of immunocomplexesof immunocomplexes

MBL PATHWAYMBL PATHWAYMicrobial surfacesMicrobial surfacesMBL PATHWAYMBL PATHWAY

Microbial surfacesMicrobial surfacesALTERNATIVE PATHWAYALTERNATIVE PATHWAY

Microbial surfacesMicrobial surfacesALTERNATIVE PATHWAYALTERNATIVE PATHWAY

Microbial surfacesMicrobial surfacesMBL-MASP2MBL-MASP2MBL-MASP2MBL-MASP2

C1sC1sC1sC1s

C4bC4bC4bC4b

THE COMPLEMENT SYSTEMTHE COMPLEMENT SYSTEM

MBL TETRAMER

N-terminal

collagen first region

DRC

Bacterial surface

Proteases (masp)

hexose

Disulfur bond

Activation C’

collagen second region

BBBB

AAAA

CCCC

DDDD

Structure of MBL polipeptidic chain Structure of MBL polipeptidic chain Structure of MBL polipeptidic chain Structure of MBL polipeptidic chain

Carbohidrate Recognition Domain (CRD)Carbohidrate Recognition Domain (CRD)Carbohidrate Recognition Domain (CRD)Carbohidrate Recognition Domain (CRD)

Alpha helix region. Interacts with CRDAlpha helix region. Interacts with CRD and determines its spatial orientationand determines its spatial orientationAlpha helix region. Interacts with CRDAlpha helix region. Interacts with CRD

and determines its spatial orientationand determines its spatial orientation

Collagen region. Functions: fagocytosis, opsonizationCollagen region. Functions: fagocytosis, opsonizationand protease binding for complement activation and protease binding for complement activation

Collagen region. Functions: fagocytosis, opsonizationCollagen region. Functions: fagocytosis, opsonizationand protease binding for complement activation and protease binding for complement activation

Terminal NH2 segment. Oligomerization through Terminal NH2 segment. Oligomerization through N-terminal cisteins by disulfur bondsN-terminal cisteins by disulfur bonds

Terminal NH2 segment. Oligomerization through Terminal NH2 segment. Oligomerization through N-terminal cisteins by disulfur bondsN-terminal cisteins by disulfur bonds

MBL gen polymorphismsMBL gen polymorphismsMBL gen polymorphismsMBL gen polymorphisms

PromotorPromotorPromotorPromotor Exon 1Exon 1Exon 1Exon 1

Serum MBL levels related with different haplotipesSerum MBL levels related with different haplotipesSerum MBL levels related with different haplotipesSerum MBL levels related with different haplotipes

High

(>1000 ng/ml)

HYPA

LYQA

LYPA

Homozygous

Sufficient

High

(>1000 ng/ml)

HYPA

LYQA

LYPA

Homozygous

Sufficient

Medium

(500-1000 ng/ml)

HYPA

LYQA

LYPA

LXPA

Heterozygous

sufficient

Medium

(500-1000 ng/ml)

HYPA

LYQA

LYPA

LXPA

Heterozygous

sufficient

Low

(200-500 ng/ml)

HYPD

LYQC

LYPB

HYPA

LYQA

LYPA

Heterozygous

Sufficient-insufficient

Low

(200-500 ng/ml)

HYPD

LYQC

LYPB

HYPA

LYQA

LYPA

Heterozygous

Sufficient-insufficient

Very Low

(<200 ng/ml)

HYPD

LYPB

LYQC

LXPA

Homozygous

insufficient

Very Low

(<200 ng/ml)

HYPD

LYPB

LYQC

LXPA

Homozygous

insufficient

MBL levels in relation with haplotypesMBL levels in relation with haplotypesMBL levels in relation with haplotypesMBL levels in relation with haplotypes

Homozygous defficientHomozygous defficient

MBL binding to different microorganismsMBL binding to different microorganismsMBL binding to different microorganismsMBL binding to different microorganisms

+++

Candida

Aspergillus

S. aureus

S. pyogenes

Bifidobacterium

Veillonella

+++

Candida

Aspergillus

S. aureus

S. pyogenes

Bifidobacterium

Veillonella

++

E. coli

Klebsiella

Haemophilus influenza B

++

E. coli

Klebsiella

Haemophilus influenza B

+

S. agalactiae

S. pneumoniae

S. epidermidis

Pseudomonas

Enterococcus

Clostridium

Bacterioides

+

S. agalactiae

S. pneumoniae

S. epidermidis

Pseudomonas

Enterococcus

Clostridium

Bacterioides

MBL defficiency and susceptibility MBL defficiency and susceptibility to to bacterial infectionsbacterial infections


Meningococcal InfectionMeningococcal Infection

Frequency of homozigous MBL-variants alleles in Frequency of homozigous MBL-variants alleles in hospitalized hospitalized patientspatients

7,7% vs. 1,5% in non-infectious controls7,7% vs. 1,5% in non-infectious controlsOR 6,5 p = 0.0006OR 6,5 p = 0.0006

Frequency in Frequency in general populationgeneral population::8,3% vs. 2,3% in healthy controls8,3% vs. 2,3% in healthy controls

OR 4,5 p = 0.06OR 4,5 p = 0.06

Hibberd ML. Lancet 1999;353:1049

Pneumococal infectionPneumococal infection

Defficient homozygousDefficient homozygous ControlsControls OR OR p p

28/229 (12%)28/229 (12%) 18/353 (5%)18/353 (5%) 2,592,59 0.0020.002

11/108 (10%)11/108 (10%) 36/679 (5%)36/679 (5%) ------ 0.0460.046



Roy S. Lancet. 2002;360:1176.

MBL levels in MBL levels in elective abdominal surgeryelective abdominal surgeryand incidence of bacterial infectionsand incidence of bacterial infections

MBL levels in MBL levels in elective abdominal surgeryelective abdominal surgeryand incidence of bacterial infectionsand incidence of bacterial infections

N=172 patientsN=172 patients N infections: 10 (0,58%)N infections: 10 (0,58%)

M. Siassi. Biochem Soc Tras 2003;31:774

MBL defficiency associated with MBL defficiency associated with recurrent bacterial infectionsrecurrent bacterial infections

MBL defficiency associated with MBL defficiency associated with recurrent bacterial infectionsrecurrent bacterial infections

Gomi K. Chest 2004; 126:95–99

Recurrent vaginal candidiasisRecurrent vaginal candidiasis

Babula CID 2003 Sep 1;37(5):733 Babula CID 2003 Sep 1;37(5):733

MBL defficiency and susceptibility MBL defficiency and susceptibility to to fungal infectionsfungal infections


Chronic necrotizing pulmonary AspergillosisChronic necrotizing pulmonary Aspergillosis

Defficients Haplotypes Defficients Haplotypes In ControlsIn Controls ppin CNPAin CNPA

7/10 (70%)7/10 (70%) 20/82 (25%)20/82 (25%) 0,0040,004

Crosdale JID 2001Crosdale JID 2001



MBL defficiency and MBL defficiency and severityseverity of infections of infections

Low MBL (n=13) 9 (33.3) 4 (11.4)

Normal MBL (n=49) 18 (67.6) 31 (88.6)

Bacteraemic PyelonephritisN = 27

Non Bacteraemic PyelonephritisN = 35

P=0.036 2 test

Smithson A. 2005 ECCMID . P-1824

MBL defficiency and MBL defficiency and severityseverity of infections of infections

Low MBL (n=13) 4 (57) 9 (16.3)

Normal MBL (n=49) 3 (43) 46 (83.7)

Pyelonephritis with septic shockN = 7

Pyelonephritis without septic shockN = 55

P=0.030 Fisher exact test

Smithson A. 2005 ECCMID . P-1824

CellularCellularImmunityImmunity

Humoral Humoral InmunityInmunity

Innate immunityInnate immunity

Prospective study (feb-oct 2005) BMT and infectionsFollow-up 6 months Periodic MBL serum levels determinations

RESULTS

- 12 (50%) autologous and 12 (50%) alogenic.

- 55% of infectious episodes: during neutropenic period.

- 63% bacterial; 26% viral, 9% fungal

- 6 (25%) died because an infectious complication

MBL Serum levels and Susceptibility to opportunistic Infections in bone marrow transplant patients

MBL<1000 *gram positive inf Crosstabulation

Count

8 3 11

7 2 9

15 5 20

no

si

MBL<1000

Total

no yes

gram positive infection

Total

MBL<1000 * gram negative infec Crosstabulation

Count

4 7 11

3 6 9

7 13 20

no

si

MBL<1000

Total

no yes

gram negative infection

Total

P = 1

P = 0.16

MBL<1000 * infeccion viral Crosstabulation

Count

4 6 10

8 2

12 8 20

no

si

MBL<1000

Total

n0 si

infeccion viral

Total

P = 0,16

10

P = 1

0

500

1000

1500

2000

2500

3000

3500

4000

4500

Maximum MBL serum levelsng/mL

Confirmed fungal infection-Pulmonary Aspergilosis -Pulmonary Mucormicosis-Systemic Candidiasis

MBL<1000 fungal infection no/yes Crosstabulation

Count

11 11

6 3 9

17 3 20

no

si

MBL<1000

Total

no yes

fungal infection no/yes

Total

P = 0,07

Polymorphisms of the Mannose-Binding Lectin Gen and Susceptibility to Opportunistic Infections

in HIV-Infected Patients

0/0n=39

527 (252)

36579 (152237)

CD4 count, mean (SD)

Viral load, mean (SD)

A/A or A/0n=151

460 (304)

48831 (154112)

p

0.21

0.66

Genotypes

JP Horcajada et al. ICAAC 2004JP Horcajada et al. ICAAC 2004

S. pneumoniae

0/0n=39

7 (18)

1 (2.5)

7 (18)

Pneumococcal bacteremia

Recurrent pneumococcal

bacteremia

Recurrent pneumonia

A/A or A/0n=151

32 (21)

5 (3.3)

17 (11)

p

0.65

1

0.28

Genotypes


Candidiasis

0/0n=39

1 (2.5)

5 (13)

1 (2.5)

7 (18)

Oral (Muget), n(%)

Esophageal, n(%)

Vaginal, n(%)

Any candidiasis, n(%)

A/A or A/0n=151

7 (4.6)

18 (12)

4 (2.6)

29 (19.2)

p

1

1

1

0.96

Genotypes


Virus

0/0n=39

1 (2.5)

4 (10.2)

5 (13)

1 (2.5)

0

Cytomegalovirus

Herpes Zoster

Recurrent Herpes simplex

Progressive multifocal

leukencephalopathy

Molluscum contagiosum

A/A or A/0n=151

7 (4.6)

32 (21)

5 (3.3)

2 (1.3)

4 (2.6)

p

0.20

0.15

0.03

0.50

0.58

Genotypes


Other OI

0/0n=39

1 (2.5)

3 (7.7)

1 (2.5)

3 (7.7)

2 (5.1)

0

Toxoplasmosis

Pneumocystis carinii

MAI

Hairy leukoplakia

Condiloma

Non-TB Mycobacteria

A/A or A/0n=151

6 (3.9)

10 (6.6)

2 (1.3)

3 (1.9)

13 (8.6)

1 (0.6)

p

10.52

0.50

0.10

0.73

1

Genotypes


Tuberculosis

0/0n=39

1 (2.5)

1 (2.5)

0

0

2 (5.1)

Pulmonary, n(%)

Lymph node, n(%)

Bone, n(%)

Milliary, n(%)

Any TB, n(%)

A/A or A/0n=151

15 (10)

3 (1.9)

1 (0.6)

8 (5.3)

27 (18)

p

0.20

1

1

0.35

0.048

Genotypes


• MBL is a key protein of the innate immune systemMBL is a key protein of the innate immune system

• MBL serum level is genetically determinedMBL serum level is genetically determined

• Genetic polymorphisms are very prevalent Genetic polymorphisms are very prevalent

• There is a higher predisposition for some infections in There is a higher predisposition for some infections in

MBL-deficient patients MBL-deficient patients

• MBL is a key protein of the innate immune systemMBL is a key protein of the innate immune system

• MBL serum level is genetically determinedMBL serum level is genetically determined

• Genetic polymorphisms are very prevalent Genetic polymorphisms are very prevalent

• There is a higher predisposition for some infections in There is a higher predisposition for some infections in

MBL-deficient patients MBL-deficient patients

Conclusions (I)Conclusions (I)

• MBL defficiency is associated with MBL defficiency is associated with higher severityhigher severity of of infections infections

• In bone marrow transplant MBL deficiency is associated In bone marrow transplant MBL deficiency is associated

with a higher incidence of with a higher incidence of invasive fungal infectionsinvasive fungal infections..

• No relation between low MBL levels and the incindenceNo relation between low MBL levels and the incindence

bacterial / viral infections and in these patientsbacterial / viral infections and in these patients

• MBL defficiency is associated with MBL defficiency is associated with higher severityhigher severity of of infections infections

• In bone marrow transplant MBL deficiency is associated In bone marrow transplant MBL deficiency is associated

with a higher incidence of with a higher incidence of invasive fungal infectionsinvasive fungal infections..

• No relation between low MBL levels and the incindenceNo relation between low MBL levels and the incindence

bacterial / viral infections and in these patientsbacterial / viral infections and in these patients

Conclusions (II)Conclusions (II)

• In HIV-infected patients MBL deficiency is associated with In HIV-infected patients MBL deficiency is associated with

a higher incidence of a higher incidence of recurrent herpesrecurrent herpes..

On the contrary, tuberculosis is more frequent in patientsOn the contrary, tuberculosis is more frequent in patientsWith With normal or high MBL levelsnormal or high MBL levels. .

• MilliaryMilliary tuberculosis is not detected in MBL-deficient tuberculosis is not detected in MBL-deficient

HIV-infected patients.HIV-infected patients.

• In HIV-infected patients MBL deficiency is associated with In HIV-infected patients MBL deficiency is associated with

a higher incidence of a higher incidence of recurrent herpesrecurrent herpes..

On the contrary, tuberculosis is more frequent in patientsOn the contrary, tuberculosis is more frequent in patientsWith With normal or high MBL levelsnormal or high MBL levels. .

• MilliaryMilliary tuberculosis is not detected in MBL-deficient tuberculosis is not detected in MBL-deficient

HIV-infected patients.HIV-infected patients.

Conclusions (III)Conclusions (III)

Documents

Innate Immunity: The First Line Against Infections