SISTEM PERTAHANAN TUBUH

ALAMI DIDAPAT

Bersifat fisik

Bersifat larutan

1. Kulit2. Silia3. Selaput

lendir

Seluler Spesifik Non Spesifik

Humoral

Sel B:Antibodi

Seluler

Sel-T

1. Fagosit2. Sel NK

1. Biokimia a. As.

Lambung b. Lisozim c. Laktoferin

2. humorala. Komplemenb. C-Reaktif Protein

(CRF)

Antigens – substances that the body regards as foreign

• Bacteria

• Fungi

• Viruses

• Parasites

• Allergens

• Toxins

E.Coli Bacteria

Antigens:

• Have unique, consistent surface patterns

• Patterns cause body to recognize antigens as enemies (musuh)

• Contain surface features called antigenic determinants (binding sites; epitop)

First line of defence: physical barrier

Second line of defence :innate/non-specific immune system

Third line of defence: learned/adaptive immune system

Immune system

First line of defence

Skin & mucous membranes Enzymes Natural microbial flora Complement protein

Second line of defence :innate/non-specific immune system

Phagocytes Natural killer cells (NK cells) Granulocytes Macrophages

Third line of defence :learned/adaptive immune system

Antibodies Lymphocytes T- cells cellular immune defense B-cells humoral immune defense

Lymphatic Lymphatic SystemSystem

• Primary immune system component (Disease Defense System)

• Functions:

• To control flow of lymph fluid

• To produce lymph system components

• To filter lymph fluid and blood

Lymphatic System Lymphatic System StructuresStructures

1. Lymph Fluid

• Interstitial fluid (fluid between cells)

• Clear, colorless tissue fluid

• Helps “feed” cells with nutrients

• Moves hormones around body

• Removes & transports waste from cells

2. Lymph Vessels (capillaries)

• Thin-walled tubes separate from blood vessels

• Contain valves to prevent “backflow”

• Move lymph fluid into lymph nodes for filtering

Lymphatic System Lymphatic System StructuresStructures

3. Lymph Nodes

• Filter lymph fluid

• Remove bacteria and viruses

• Store white blood cells

Lymphatic System Lymphatic System StructuresStructures

4. Tonsils

• Masses of lymph tissue

• Contain lymph nodes and lymph vessels

• Protect nose and upper throat

Lymphatic System Lymphatic System StructuresStructures

5. Spleen

• Lymphatic tissue located in the cranial thoracic region

• Produces white blood cells

• Filters blood

• Stores red blood cells

Lymphatic System Lymphatic System StructuresStructures

6. Thymus

• Lymph gland located medially in the cranioventral area of the thoracic cavity

• Most active in young animals

• Place where some white blood cells produced in bone marrow reproduce and mature

Lymphatic System Lymphatic System StructuresStructures

7. Bone Marrow

• Located in the epiphysis of long bones

• Produces white blood cells

Lymphatic System Lymphatic System StructuresStructures

1. White Blood Cells (Leukocytes)

• Lymphocytes

• Attack specific antigens

• Formed in lymph structures & bone marrow

• Monocytes

• Very large

• Formed in bone marrow

• Mature in thymus

Lymphatic System Lymphatic System ComponentsComponents

2. Macrophages

• Phagocyte (eats cells)

• Develop from monocytes

• Eats invading cells

• Eats disabled antigens

Lymphatic System Lymphatic System ComponentsComponents

3. T-Cells

• A type of lymphocyte

• Produced in bone marrow

• Mature in thymus

• Coordinate immune system defenses

• Kill antigens directly on contact

Lymphatic System Lymphatic System ComponentsComponents

4. B-Cells

• Also called plasma cells

• A type of lymphocyte

• Produced in bone marrow

• Do not kill antigens directly

• Produce and release antibodies

Lymphatic System Lymphatic System ComponentsComponents

5. Antibodies

• Called Immunoglobulins (Ig)

• Produced by B-Cells

• Composed of proteins

• Attack and kill specific antigens

• “Lock and Key” method of attack

Lymphatic System Lymphatic System ComponentsComponents

Struktur Imunoglobulin

Rantai berat/panjang (Heavy Chains) & ringan/pendek (Light Chains)

Semua rantai disatukan oleh ikatan disulfida Dalam rantai (Intra-

chain) Antar Rantai (Inter-

chain)CH1

VL

CL

VH

CH2 CH3

Wilayah Engsel (Hinge Region)

karbohidrat

Ikatan disulfida

Struktur Imunoglobulin

Wilayah Variabel & Konstant VL & CL

VH & CH

Wilayah Engsel (Hinge Region) CH1

VL

CL

VH

CH2 CH3

Wilayah Engsel (Hinge Region)

karbohidrat

Ikatan disulfida

Struktur Immunoglobulin Domain penting

VL & CL

VH & CH1 - CH3 (kadang ada CH4)

Oligosakarida

CH1

VL

CL

VH

CH2 CH3

Wilayah Engsel (Hinge Region)

Karbohidrat

Ikatan Disulfida

Fragmen Imunoglobulin: Hubungan Struktur – Fungsi

Tempat Ikatan dengan antigen (Ag Binding;

Fab)

Berikatan dengan Reseptor Fc

Fab Ag binding

Fc Fungsi Efektor

F(ab’)2

Fragmen Imunoglobulin:

Pepsin

Fc Peptides

F(ab’)2

IgG - Gamma () heavy chains IgM - Mu () heavy chains IgA - Alpha () heavy chains IgD - Delta () heavy chains IgE - Epsilon () heavy chains

Klas Immunoglobulin

Struktur Monomer (7S)

IgG

IgG1, IgG2 and IgG4 IgG3

StrukturStrukturSifat-sifat◦ Ig serum utama◦ Ig utama dalam cairan extravaskuler◦ Transfer Plasenta◦ Fiksasi komplemen◦ Berikatan dengan Reseptor Fc receptors

Fagosit - opsonisasi Sel K - ADCC

IgG

Struktur Pentamer (19S) domain ekstra

(CH4) Rantai J

IgM

CH4

J Chain

Struktur Sifat-sifat

Ig serum ketiga terbanyak

Ig pertama yang dibuat oleh fetus dan sel B Ig permukaan sel B

Fiksasi komplemen

IgM

Bgn Ekor

Struktur Serum - monomer Sekresi (sIgA)

Dimer (11S) Rantai J Komponen

sekrotori

IgA

Rantai J

Komponen Sekretori

Struktur Sifat-sifat

Ig no. 2 terbanyak dalam serum Ig sekretori utama (Kekebalan lokal

dan mukosa) Airmata, Air liur, sekresi lambung

dan paru-paru

IgA

Struktur Monomer Domain ekstra

(CH4)

IgE

CH4

Struktur Sifat-sifat

Paling rendah dalam serum Berikatan dengan basofil dan sel

mast Bertanggung jawab dalam alergi Infestasi Parasit (Cacing)

Berikatan dengan Reseptor Fc Eusinofil

IgE

Bahan yg dapat merangsang respon imun Dibedakan menjadi:

- imunogen:bahan yg dpt menimbulkan respon imun- hapten: molekul yg dpt bereaksi dg antibodi tetapi tdk dapat merangsang pembentukan antibodi

Epitop: bagian antigen yg dpt menginduksi pembentukan antibodi

Epitop dapat diikat secara spesifik oleh bagian dr antibodi atau reseptor pd limfosit

ANTIGEN

Type epitop of ANTIGEN

Unideterminant univalen

Unideterminant multivalen

Multideterminant univalen

Multideterminant multivalen

Menurut Sifat kimiawinya Polisakarida Lipid Asam nukleat protein

PEMBAGIAN ANTIGENPEMBAGIAN ANTIGEN

Antibodies – disease-fighting proteins produced by the body in

response to a specific antigen

• Have binding sites that match antigenic determinants on antigens

• Binding sites are chemical, not physical

The Antigen/Antibody The Antigen/Antibody ResponseResponse

“The Lock and Key“The Antigen/Antibody The Antigen/Antibody

ResponseResponse• Antibody binding sites match antigen

surfaces like a key fits into a lock

• Most antigen binding sites are keyed to a matching antibody in a healthy immune system.

“Search and Destroy”

The Antigen/Antibody The Antigen/Antibody ResponseResponse

• Antigens have many binding sites on their surfaces.

• Antibody molecules locate antigens and bind to the surfaces, sometimes in chains.

• Antibodies disable (kill) antigens

• Antibodies block antigens from attaching to body cells

• Antibodies “call” macrophages to come and consume disabled antigens

The Antigen/Antibody The Antigen/Antibody ResponseResponse

“Shackled” Prisoners = membelenggu narapidana

How does it work?The Antigen/Antibody The Antigen/Antibody

ResponseResponse

• Antigens invade body

• Patrolling macrophages locate, recognize antigens as enemies, and ingest them.

• Macrophages “read” antigens and encode T-cells with antigen binding site instructions.

• Macrophages “dispatch” T-cells with antigen codes.

How does it work?The Antigen/Antibody The Antigen/Antibody

ResponseResponse• T-cells pass antigen binding instructions

to B-cells (plasma cells)

• Plasma cells produce and release antibodies that match antigen binding sites

How does it work?The Antigen/Antibody The Antigen/Antibody

ResponseResponse

• Macrophages find disabled antigens and consume them.

• Some T-cells “remember” antigens for faster response the next time an attack occurs.

Search & DestroySearch & Destroy

The Army WithinThe Army Within

1. Good general health

2. Good nutrition

3. Vaccines (specific antigens)

4. Antitoxins (antibodies)

5. Immune system boosters

• Stimulate lymphocyte production

• Improve lymphocyte response time

How can we help it fight it’s battles?

Phagocytosis

Neutrophile to go out from blood vessel to site of infection: diaphedesis

Specific oligosaccharide (of neutrophil)bind with lectin (of endothelial cells)

opsonization of Bacteria in plasma by opsonin particle, to phagocyte

Beautiful Macrophage in action

Neutrophil phagocyte of streptococcus

Fagositosis: letupan oksisidatif(Oxidative Burst)

Rangkaian gambar mikroskopis neutrofil yang bergerak menuju dan memakan jamur (bulatan oval). Penambahan indikator warna nitroblue tetrazolium (NBT) menunjukkan bahwa sel leukosit tersebut mampu membunuh jamur dengan menggunakan kemampuan oksidatifnya yang mematikan (H202, NO,

dlsb.)

Respiratory burstRespiratory burst

H2O2 + 1O22O2

- + 2H+

Superoxide dismutase

H2 O2 + Cl-

myeloperoxidaseOCl- + H2O

H2O + O22 H2 O2

catalase

OCL- + H2O1O2 + Cl- + H2O

                               

 

Sel Pembunuh Alami (Natural Killer Cells/NK)

Setidaknya ada dua sel pembunuh:—sel T sitotoksik (Tc/T8/Tcd8+) dan NK.

Dalam aksinya Tc perlu mengenal antigen khas dan NK tidak memerlukannya. Keduanya mempunyai granula penuh bahan kimia mematikan

Fagosit dan Granulosit•Leukosit besar yang dapat ‘menelan’ dan

mencerna bahan asing•Monosit dalam darah dan makrofag di

jaringan, neutrofil dalam darah dan dapat pindah ke jaringan

bila diperlukan •Makrofag adalah sel serba-guna:

sebagai pemakan, sintesis berbagai bahan kimia yang kuat, dan berperan penting dalam mengaktivkan sel T

•Neutrofil tidak hanya fagosit tapi juga granulosit: punya granula penuh bahan kimia potensial yang berperan dalam penghancuran mikroba dan reaksi radang

•Granulosit yang lain adalah eosinofil dan basofil

•Sel Mast adalah sel bergranula dalam jaringan