immunity and vaccines for exam 3

SO.... HOW DO YOU FIGHT

BACK?

Monday, February 27, 2012

HOST FACTORS: WHAT YOU DO TO FIGHT INFECTIONSImmune System Overview

Factors that affects the immune status of the host

age, nutrition, hygiene, etc


BEFORE THE IMMUNITY...


OVERVIEW: HOW WE FIGHT INFECTIONS...

www.youtube.com/watch?v=T_4TrNRa3v8Monday, February 27, 2012

http://www.youtube.com/watch?v=T_4TrNRa3v8

http://www.youtube.com/watch?v=T_4TrNRa3v8

THE CELLS...


INNATE HUMORAL : THE COMPLEMENT


THE COMPLEMENT SYSTEM & THEIR FUNCTION


INNATE CELLULAR

MONOCYTES

dendritic cells (antigen presenting cells)

macrophages (ingest foreign cells)

NATURAL KILLER CELLS

releases proteins to kill foreign cells

GRANULOCYTES

mast cells (releases histamines during allergic reactions)

neutrophils, eosinophil, basophils


DENDRITIC CELLS & ANTIGEN PRESENTATION


MACROPHAGES


NATURAL KILLER CELLS


MAST CELLS


THE PHILS...

NEUTROPHILS

EOSINOPHILS

BASOPHILS

INFLAMMATION


ADAPTIVE HUMORAL


ADAPTIVE CELLULAR

B cells

plasma cells = differentiates to antibodies

memory cells = for secondary exposure to antigens

Th

helpers

activates humoral response (immune cells)

Tc

cytotoxic

kills and clears


B CELLS


T HELPER CELL


CYTOTOXIC T CELL


MHC CLASSES

A. Which T cell will perform

B. Which pathogen type

Intracellular ExtracellularMonday, February 27, 2012

INFECTION BY BACTERIA

Bacterial Infections Are Eliminated By Humoral Immunity

Exception: intracellular bacteria Ex. TB

Antibodies Eliminate Bacteria Or Bacterial Toxins

Opsonization Of Bacteria

Neutralization Of Toxins

Exotoxins (Ex. Diptheria)

Endotoxins (Ex. LPS)

Lysis Of Bacteria Thru Complement Pathway

Bacteria Enter Host Thru

Respiratory Tract, GI Tract, Genitourinary Tract, Skin


EVASION BY BACTERIA

Some Bacteria Have Pili

Some Bacteria Secrete Adhesion Molecules (Bordetella pertussis)

Immune System Response To Attachment Is IgA

Prevents Attachment

Some Bacterial Evade IgA Thru Proteases That Decrease ½ Life Of IgA

Ex. Haemophilus influenzae

Some Bacteria Avoid Phagocytosis By Surrounding Themselves In A Polysaccharide Capsule. Ex. Streptococcus pneumoniae


OVERZEALOUS IMMUNE SYSTEM NOT BENEFICIALBacterial Septic Shock

Predominant Cytokines Involved: IL-1 and TNF-α

Source: MΦ

Intracellular Bacteria Cause Granulomas

Extensive Tissue Damage

Ex. Tuberculosis

In Tuberculosis, MΦ Ingest MTB But Cannot Digest It

Eventually Burst - Releasing Bacilli

MΦ And TH1 Cells Form Granulomatous Lesion, Containment+Destruction Of Healthy Tissue

INF-γ and IL-12 Are Crucial In Eliminating Pathogen


INFECTION BY VIRUSES

The Immune Response Against Virus Is Primarily Mediated Thru Interferons

Double stranded RNA induces production of IFN

Main producers of IFNα and IFNβ are pDCs

TLR-3 (dsRNA); TLR-7 (ssRNA)

Interferons produce an anti-viral state

A state that inhibits viral replication

A state that inhibits viral infection


Antibody Protection Against Viruses

Antibodies Bind To Viral Surface Antigens

Protect against re-infection

Huge amounts of secretory IgA in lumen block viral attachment

Viral Entry Into Cells Is Mediated Thru Receptors

Influenza virus binds to sialic acid on glycoproteins

Rhinovirus binds to ICAMs

If Receptor Is Blocked, Infection Is Blocked

Oral Polio vaccine Relies On IgA Production


Antibodies Are Efficient In Preventing Infection




Once Infection Has Occurred, Only Cell Mediated Immunity Can Eliminate Infected Cells




Once Infection Has Occurred, Only Cell Mediated Immunity Can Eliminate Infected Cells

Examples Of Cell Mediated Immunity

TH1, CTL Are the major participants



TH1 Produce IFN-γ, IL-2, and TNF-α

IL-2 expands CTL-P

IFN-γ induces antiviral state

IL-2 and IFN-γ activate NK cells (first line of defense)



TH1 Produce IFN-γ, IL-2, and TNF-α

IL-2 expands CTL-P

IFN-γ induces antiviral state

IL-2 and IFN-γ activate NK cells (first line of defense)

CTL (cytotoxic lymphocytes)

Peaks 7-10 days post infection

Eliminate virally infected cells



VACCINES & VPD


THERE ARE 2 WAYS TO PROTECT YOURSELF...A.

B.


BACTERIAL VACCINESBacteria Disease Antigen Efficacy

Streptococcus pneumoniae

Pneumonia Capsular polysaccharide

85%

Neisseria meningitidis

meningitis Capsular polysaccharide

85%

Hemophilus influenzae

meningitis Capsular polysaccharide

85%

Corynebacterium diphtheriae

Diphtheriae Toxoid >90%

Clostridium tetani tetanus Toxoid >90%

Bordetella pertussis Whooping cough Killed organism >90%

Mycobacterium bovis (BCG)

Tuberculosis Live attenuated 0 – 70 %

Salmonella typhi Typhoid fever Killed/Live attenuated

80%


IMMUNIZATION FOR INFANTSVaccine Reason for Immunization

BCG Given at the earliest possible age protects against the possibility of infection from

family members

DPT Early start with DPT reduces chance of severe pertussis

OPV Protection against polio increased the earlier the OPV is given

Hepatitis B Early start of HBV vaccination reduces chance of being infected and becoming a

carrier

Measles At least 80% of measles can be prevented by immunization at this age


SCHEDULEAge Diseases to be immunized against

Birth Tuberculosis

6 weeks DPT; Polio; HBV



9 months Measles


SIDE EFFECTS OF BCG30 minutes wheal disappears2 weeks: a small red tender swelling 10 cm appears

3 weeks: swelling becomes a small abscess which then ulcerates

12 weeks: course from vaccination to healing & scarification

SIDE EFFECTS:1. Koch’s phenomenon- an acute

inflammatory reaction appearing within 2-4 days of vaccination

2. Deep abscess at vaccination site – due to subcutaneous or deeper injection (I & D)

3. Indolent ulceration- an ulcer which persists after 12 weeks or > 10cm deep (Tx –INH powder)

4. Lymph node enlargementMonday, February 27, 2012

SIDE EFFECTS DPTSIDE EFFECTS:Fever: many children develop fever after injection , lasting only one day; fever that lasts more than 24 hours after a dose of DPT is not due to the vaccine but to other causes

Local Soreness: Pain or swelling at injection site

Advice/ Management

Antipyretic or tepid sponge bath

Reassure mother that swelling needs no treatment and will disappear within 3-4 days


SIDE EFFECTS DPTSIDE EFFECTS:Abscess: If this appears a week or more after the injection, it is due to wrong technique. Either the vaccine was not injected deep enough or the needed was not sterile

Convulsions: Very rare; occurs more in >3 months; usually due to pertussis component of the vaccine

Advice/ Management

Incision and drainage is necessary

If convulsions occur, give proper management and do not continue the normal course


SIDE EFFECTS MEASLES VACCINE

SIDE EFFECTS:Fever and rash: Children may develop fever after 5-7 days from the time of vaccination

Fever lasts only from 1-3 days.Sometimes a mild rash appears

Advice/ Management

Reassure the mother and advise antipyretic for the child


TETANUS TOXOIDVaccine Minimum age/

intervalPercent

protectedDuration of protection

TT1 As early as possible during pregnancy

TT2 At least 4 weeks later 80% * Infants born to the mother protected from neonatal tetanus; 3 years protection to mother

TT3 At least 6 months later 95% * Infants protected; 5 years protection to mother

TT4 At least one year later 99% * Infants protected; 10 years protection to mother

TT5 At least one year later 99% Lifetime protection for mother; * all infants born to that mother will be protected


VACCINES AND POLIO ERADICATION EFFORTS (smallpox as model)

Parungao-Balolong 2011Monday, February 27, 2012

MEASLES & HERD

IMMUNITY

thepaltrysapien.com


EMERGING & RE-EMERGING INFECTIONS


PUBLIC HEALTH PLANNING & INTERVENTION

Disaster and Outbreak Preparedness

Accessibility to Intervention and Good Clinical Management

Environmental Sanitation and Hygiene

Research: Diagnostics, Therapy and Pathogenic Mechanisms

Surveillance and Prevention Control Programs

Health Promotion and Awareness Ads and Campaigns


END OF BIO 120 LECTURES


immunity and vaccines for exam 3

Technology

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ifn activatenk cells

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bacteriasome bacteria

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infectiononce infection

b cellsmonday

adaptive humoralmonday