HANSEN’S DISEASE : IMMUNOPROPHYLAXIS &IMMUNOTHERAPY

Introduction

• Vaccine : Lat ‘ La Vaccha’ – ‘Cow’

• Chronic infectious disorder with long, variable incubation period and high generation time

• Immunomodulators regulate immune system prevent Neuritis / Reactions to live / dead bacilli with Chemotherapy targeted at live bacilli

Immunoprophylaxis

• Enhance Host Immunity to control infection by provoking protective repsonse to AGs

Types of Vaccines :

• Killed (No inf / high Antigenicity)• Live, Attenuated (Low Virulence / High AG – natural

history)• Cross-reacting AGs ; Non-pathogenic• Immunogenic Subunits

Vaccines in use

• BCG

• HKML / HKML-A

• Mw

• M vaccae

• ICRC

BCG

• 20th C ; used for immunization in cattle / humans against Mtb

• Live, Attenuated

• M bovis derivative

• Modest response alone

• may prevent BT / BB

• Used with HKML / HKML-A to increase AG and initiate protective response

Mw

• M welchii - HK

• Mycobacterium indica praNII

• cultivable Non-pathogenic Mycobacterium used for Cross-sensitization

• Shares AG with ML / Mtb (65/18/13 kDa)

M vaccae

• Derived from cowdung

• HK

• Cultivable non-pathogenicbacteria with shared AG

• Commercially available

ICRC bacillus

• Indigenous, HK

• Cultivable MAIC or from Leprosy patients

• HMW Glycolipoprotein PP-I Sonicated Subunit vaccine in Ph I / II Clincial trials In India

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Immunotherapy

• Addition of Immunomodulators and Cross-reacting antigens to regulate host immunity and achieve :-

– Higher Bacillary Clearance (Viable / Dead)– Reduce Incidence and severity of Reactions /

Neuritis– Restore effective immunity prevent relapses and

re-infection– Reduce duration of treatment– Lepromin conversion

Classification

• Antigenically-related Mycobacteria with shared Ags (BCG/HKML/Mw/ICRC/M vaccae, habana, gordonnae, phlei)

• Drugs (Levamisole/Corticosteroids/Zinc/Clofazimine/Colchicine/Thalidomide/CsA)

• Other Immunomodulators (Transfer Factor/CK-Ils/AA-ML/DCC/CWC)

BCG• Maiden Immunomodulator

• 0.1 ml ID at 0-6-12-18-24 months with MB-MDT in LL patients

• Lepromin Conversion / Smear negativity / fall in BI / faster granuloma clearance

• No change in Reactional severity / incidence

• BCG + HKML = Beneficial in Indeterminate Hansen’s / LL / Household contacts with Histological Upgradation

Mw

• HK preparation with MB-MDT @ 0.1 mL ID (5 x 109 bacilli) as 1st dose 0.05 mL ID every 03 months (Total = 08 doses) in BL/LL patients

• Reduction in BI / MI, Granuloma resolution, Smear Negativity @ 52 months, reduction in ENL incidence

• ICRC + MB-MDT Lepromin Conversion with RRs reported

• Other Cross-Sensitizing cultivable Mycobacterium species viz gordonnae / habana / phlei are being studied

LEVAMISOLE

• Broad-spectrum Anthelminthic

• Regulates defective T-cell function

• 150 mg 2 /wk PO x 06 wks Pt on DDS 100 mg daily for 05 years showed Smear Negativity in 01 yr

ZINC

• Immunomodulator for LL / ENL

• Inhibits complement-dependent Immune complex formation / PMN chemotaxis

• Faster clinical improvement, reversal of Madarosis, histological upgradation with DDS as compared to DDS alone

Other Drugs

• Corticosteroids

• Thalidomide

• CsA

• Clofazimine

• Colchicine

• AZA

Other Immunomodulators

• LAWRENCE’S TRANSFER FACTOR transient

• CYTOKINES (IFN-G / IL-2) I/L ; local effect

• ACETO-ACETYLATED ML (AA)

• DE-LIPIDIFED CELL COMPONENTS ML (DCC)

• SOLUBLE PROTEIN CELL WALL COMPONENT (SPC)

• ISOLATED CELL WALL CORE AG (CWC)

THANK YOU