3/24/2014

1

Immunopathology Part II

Autoimmune Disease

Pathology of Transplantation

Laboratory evaluation of the Immune System

Immunodeficiency

Amyloidosis

Immune Mediated Tissue Injury

ANTIGEN

B-CELLS T-CELLS

APC

CD4 CD8

DELAYED-TYPE HYPERSENSITIVITY

CYTOTOXICITY

ANTIBODIESand IMMUNECOMPLEXES

IgE andALLERGICDISEASE

IVII, III

I

+

+

3/24/2014

2

Autoimmunity andAutoimmune Disease

Autoimmune Disease: Single-Organ And Systemic (Multiorgan)

Organ-Specific Systemic

Hashimoto thyroiditis Systemic Lupus ErythematosusAutoimmune hemolytic anemia Rheumatoid ArthritisMultiple Sclerosis Sjogren SyndromeAutoimmune Orchitis Reiter SyndromeGoodpasture Syndrome Inflammatory MyopathiesAutoimmune Thrombocytopenia Systemic SclerosisInsulin Dependent Diabetes MellitusMyasthenia GravisGraves DiseaseAutoimmune Hepatitis

Mechanisms of Autoimmunity Antinuclear Antibody IF

Homogeneous

Peripheral/rim

Speckled

Centromere

3/24/2014

3

Antinuclear Antibody IF

Anti dsDNA: Crithidia lucida

Extractable Nuclear Antigens:“Alphabet Soup”

Anti ds-DNA (native DNA): 40-60% SLE (< 5% other)Anti-histone: 50-70% SLE (< 5% other)Anti-Smith (Sm): 20-30% SLERNP (ribonucleoprotein):

SS-A (Ro): 70-95% SS, 30-50% SLESS-B (La): 60-90% SS, 10-15% SLE

Scl-70 (DNA topoisomerase I): 28-70% PSS10-18% limited Scl.

Anti centromere: 90% limited Scl., 22-36% PSS

Anti-Jo-1 (Histidyl tRNA synthetase): 25% myositis

Autoantibodies: LE Cell

Systemic Lupus Erythematosus

3/24/2014

4

Systemic Lupus ErythematosusA systemic autoimmune disease

Incidence: 1/2500 (40/100,000) N. European

SKIN

KIDNEY

BLOOD CELLS

CNS

LUNGS,OTHER

Immune-mediatedInflammation

JOINTSCARDIO-VASCULAR

“GarbageDisposal

Hypothesis”

AUTOANTIBODIES IN SLE

Antinuclear antibodies:

ANA ScreenAnti-dsDNAAnti-Sm

Antiphospholipid AntibodiesAntigens: beta-2 glycoprotein, annexin

Other Autoantibodies

Pathology of SLE: Kidney

Class I Normal (LM)

Class II Mesangial

Class III Focal Proliferative

Class IV Diffuse Proliferative

Class V Membranous

Pathology of SLE: Kidney

3/24/2014

5

Pathology of SLE: Kidney Pathology of SLE: Kidney

Pathology of SLE: Kidney EM Systemic Lupus ErythematosusSkin Involvement

Pathology of SLE: Skin Pathology of SLE: Skin

3/24/2014

6

Pathology ofSLE:

Heart

Libman SachsEndocarditis

Accelerated Atherosclerosis

Pathology of SLE: Spleen

1-3: SKIN: malar rash 85%discoid rashphotosensitivity

4-6: SURFACE INFLAMMATION: oral ulcers arthritisserositis 25-45%

7: RENAL: proteinuria 50-70%casts

8: NEUROLOGICAL: seizures 25-30%psychosis

9: HEMATOLOGIC: cytopenias100%

10: IMMUNOLOGIC: anti dsDNA, Antiphospholipid, anti Sm

11: ANA

SLE REVISED CRITERIA

Systemic Lupus Erythematosus

Natural History and Prognosis:

Unpredictable course with episodic exacerbations (flares)

Patterns of autoantibody expression:

Survival1950s 4 yr survival 50%Current 15 year survival 80%

Mortality: Bi-phasic

Early: severe inflammatory disease (lupus), or infectionLate: myocardial infarction, stroke

Systemic Lupus Erythematosus:

Treatment

Minor symptoms: NSAIDSlow dose prednisone

Moderate to Severe HydroxychloroquineCorticosteroidsmycophenolate mophetilAzathioprineAnti B-cell agents: Rituximab

**Also: Aggressive modification of cardiacrisk factors

3/24/2014

7

Discoid LupusLupus Variants

Drug Induced “Lupus”

Drugs: hydralazine, procainamide, isoniazid,penicillamine

+ ANA may be only feature(anti-histone >95%)

+/- Skin and Multisystem involvement

CNS involvement rare

Sjogren Syndrome

Sicca syndrome

Mikulicz disease

Sjogren Syndrome: Salivary Gland

Sjogren Syndrome: Lymphoepitheliallesion

Sjogren Syndrome; Chronic inflammationand Atrophy

3/24/2014

8

Sjogren Syndrome: Complications: Malignant Lymphoma Scleroderma

(Progressive Systemic Sclerosis)

Diffuse Cutaneous

Localized Cutaneous

Limited: CREST

Nailbed Capillaroscopy

3/24/2014

9

Raynaud’s Phenomenon

3/24/2014

10

Progressive Systemic Sclerosis

Clinical features:

Raynaud’s phenomenonSkin changesMusculoskeletalGIPulmonaryCardiacRenal

Autoimmune Inflammatory Myopathies

Dermatomyositis

Heliotrope skin rash + myopathy (proximal to distal)

Children and adults affected

Extra muscular disease: lung

Capillaries are major target

Dermatomyositis

Polymyositis

Myopathy without skin involvement

Predominantly adult disease

Direct cell mediated infiltration of muscle

Systemic involvement: heart, lungs

3/24/2014

11

Polymyositis

Immunopathology

Pathology of Transplantation

Transplant Rejection

Increasing Graft Survival

Graft versus Host Disease

Other Complications

December 23, 1954: First Successful Kidney Transplant Boston Mass.

Mechanisms Of RejectionClassification of Rejection

Hyperacute: minutes-hoursAcute: days to years

acute cellular rejectionacute vascular rejection

Subacute: months

Chronic: years

3/24/2014

12

HyperacuteRejection

Acute Rejection

Acute VascularRejection

Chronic Rejection

3/24/2014

13

Chronic RejectionAcute Rejection, Heart

Bile Duct

Acute Rejection: Liver

Increasing Graft Survival

ABO Blood Group MatchingMHC/HLA Antigen MatchingOld: microlymphocytotoxicity

mixed lymphocyte cultureantibody screening

Current: HLA typing: DNA-based (PCR)Crossmatching by flow cytometry

Immunosuppression

Immunosuppressive Drugs

Drug Year Mechanism

Corticosteroids 1960 blockade of cytokine gene transcription lymphs, macrophages/APCs

Azathioprine 1962 blockade purine synthesisin myeloidcells

Cyclosporine 1980 inhibition of IL2 synthvia calcineurin pathwayblockade

OKT3 1980 binds to CD3 complex

Immunosuppressive Drugs

Drug Year Mechanism

Mycophenolate early90s blockade of purine Mofeteil synthesis (lymphocytes)

Tacrolimus late 90s calcineurin blockade(FK506)

Sirolimus late 90s inhibition of IL2 signal transduction

Anti-IL2 late90s binds to alpha subunitreceptor of IL-2receptor

3/24/2014

14

NEJM Vol 351:26 December 2004

Renal Allograft Survival 1988-1996

Living Related Donor Cadaveric

NEJM Vol 342 March 2000

NEJM Vol 346, No 8 2002

Graft vs Host Disease

GVHD: Skin

AcuteGVHD

Skin involvement

3/24/2014

15

GVHD: Skin

Acute GVHD: Colon

GVHD: Liver

Post-TransplantLymphoproliferativeDisorder

3/24/2014

16

Immunodeficiency DiseasesCongenital and Acquired

Assessing the Status of theImmune System

Assessing the Status of the ImmuneSystemSerum Protein Electrophoresis

Hypogammaglobulinemia

Flow Cytometry

Lymphocyte subsets

Tcell proliferation

Hyper IgM syndrome (CD40L)

Leukocyte adhesion deficiency

Cytokine expression

PNH (complement regulatoryProteins CD55, CD59)

Immunophenotyping ofleukemia, lymphoma

HLA typing

Stem cell enumeration

3/24/2014

17

CD4 LymphocyteQuantitation byFlow Cytometry

Assessing the Status of the Immune System

Lymphocyte Activation Testing

Unstimulated lymphocytes Stimulated lymphocytes

Assessing the Status of the ImmuneSystem

Skin Testing

Tuberculin Candida

Nitroblue Tetrazolium Test

CATEGORIES OF IMMUNODEFICIENCY DISORDERS

Antibody deficiencies and defects 65%

Combined antibody and cellular deficiencies 15%

Disorders of phagocytes 10%

Isolated cellular defects 5%

Complement deficiencies/disorders 5%

Other disorders of innate immunity <1%

Lymphocyte Development and Immunodeficiency

3/24/2014

18

X-Linked (Bruton’s) Agammaglobulinemia Other Humoral Immunodeficiencies

Severe Combined Immunodeficiency

Buckley, R. H. N Engl J Med 2000;343:1313-1324

Relative Frequencies of the Various Types of Severe Combined Immunodeficiency among 141 Consecutive Patients

3/24/2014

19

Gene Therapy

RetroviralVector

γc cytokinereceptor

gene

Wiskott-Aldrich Syndrome

Triad:EczemaThrombocytopenia with small plateletsRecurrent Infections

Complement Deficiencies

Early components: C1q, C2, C4C1q EsteraseC5-9

Phagocyte Deficiencies

Chronic GranulomatousDisease (CGD)NADPH oxidase deficiency

Pathology and Pathogenesisof HIV Infection

3/24/2014

20

3/24/2014

21

HIV INFECTION

Mode of Transmission and Spread

Sexual Transmission (75%)

FLUIDSEFFICIENCY OF TRANSMISSIONMODIFYING FACTORS

Parenteral

IV DRUG USETRANSFUSION

1 in 2 million units transfusedNEEDLE STICK less than 1 in 300

PerinatalINTRAUTERINE/TRANSPLACENTALINTRAPARTUMBREAST FEEDING

HIV GENOME

HIVCELL BINDING AND ENTRY

CXCR4 and CCR-5 T CELLSCCR-5 only MACROPHAGEChemokine receptors:

3/24/2014

22

HIVIntracellular life cycle

HIV

Overview ofPathogenesis

HIVMechanisms of T-cell Loss

HIVEffects of loss of Helper T cells

Natural History of HIV Infection

“set point”

3/24/2014

23

HIV INFECTIONClinical Phases:A)Acute HIV, generalized lymphadenopathyB) Symptomatic (not A or C)C) AIDS indicator conditions

T Cell (CD4) Stages:I) > 500/uLII) 200-499/uLIII) < 200/uL

Clinical and PathologicFeatures of AIDS

Acute HIV Infection

Kahn, J. O. et. al. N Engl J Med 1998;339:33-39

HIVLymphadenopathy

Primary CNSLymphoma

Kaposi’sSarcoma

3/24/2014

24

Kaposi’s Sarcoma Kaposi’s Sarcoma

Pathogenesis of Kaposi’s Sarcoma

Cervical Cancer and HPV

HIV-Associated CNS Disease

3/24/2014

25

Progressive Multifocal LeukoencephalopathyMycobacterial Disease in AIDS

M. tuberculosisM. Avium complex

M. Avium in spleen AFB stain

PneumocystisJeroveci

H&E GMS

3/24/2014

26

HistoplasmosisCryptococcusneoformans

Toxoplasmosis

Cryptosporidium

Cytomegalovirus

Jacobson, M. A. N Engl J Med 1997;337:105-114

3/24/2014

27

HIV SCREENING

ELISA (HIV 1 and 2)

POSITIVE (repeatedly)

WESTERN BLOT

POSITIVEHIV 1INFECTION

NEGATIVE

HIV 2 TESTING

INDETERMINANT

HIV 1 AbIF

HIV-1 ProviralDNA by PCR

POSITIVEHIV 1INFECTION

NEGATIVE

POSITIVEHIV 1INFECTION

NEGATIVE

REPEAT ELISA 1-3 MOS—Hi Risk

NEGATIVE

HIV: Targets for anti-retroviral therapy

Clavel, F. et. al. N Engl J Med 2004;350:1023-1035

Complex of HIV-1 Reverse Transcriptase with an RNA-DNA Duplex

Slide 7.45

Amyloidosis

3/24/2014

28

Pathogenesis of Amyloidosis

Slide 7.46

3/24/2014

29

Slide 7.47

3/24/2014

30

Localized Amyloidosis: Pancreas