I : Introduction to Immunology & The Immune System

Immunology

- Study of the reactions of a host when foreign substances (i.e bacteria) are introduced into the body.

Immunology

- The study of the body’s mechanism (i.e anaphylactic response):

• That discriminated between non-self & self

• Eliminates non-self components such as infectious agents

• Medically related consequences that arise when these mechanisms either fail or respond in an exaggerated form.

Antigens

- Foreign substances that induce a host response.

Antigens

- Antibody generator

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Antigens is all around us (t/f)

Antibody

- A glycoprotein produced by the body to neutralize & eliminate the antigens

Immunity

- Condition of being resistant to infection.

Attenuation / Change

- Making a pathogen less virulent

Attenuation / Change

- Purpose: takes a part of the weakened virus to process through heat, aging, or chemical means for the development of vaccines

Attenuation / Change

- remains the basis for many of the immunizations that are used today

heat, aging, or chemical means.

Attenuation / Change takes place through

Innate Immunity (IN)

-    The ability the body to resist infection by means of normally present, nonspecific body functions.

Innate Immunity (IN)

-    Considered non adaptive/nonspecific

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Innate Immunity (IN) (t/f)

-    Responses are the same for all pathogens/foreign substances to which one is exposed.

Adaptive Immunity (AI)

-    Type of resistance characterized by specificity for each individual & the ability to remember a prior exposure.

lymphocytes

Adaptive Immunity (AI)

-    Requires the activation of - in response to an infectious agent.

Serology         

-    The study of antigen-antibody reaction in vitro (outside)

Serology         

-    The technological application of immunologic principles in the detection & monitoring of dx states.

1798

·    Edward Jenner discovered the relationship between the exposure to cowpox & immunity to smallpox.

He injected material from cowpox to px, to develop immunity against smallpox which was called vaccination from “vacca” which means cow.

Edward Jenner

who discovered the relationship between the exposure to cowpox & immunity to smallpox.

He injected material from cowpox to px, to develop immunity against smallpox which was called vaccination from “vacca” which means cow.

vacca

cow

Edward Jenner injected material from cowpox to px, to develop immunity against smallpox which was called vaccination from “-” which means -.

1879

·    Louis Pasteur introduced the germ theory of the dx.

Louis Pasteur

1879

when & who accidentally discovered the use of attenuated vaccine while working with bacteria causing chicken cholera. (considered as the birth of immunology)

Louis Pasteur

who also developed that the body makes antibodies in response to infection in 1900.

1900

Louis Pasteur developed that the body makes antibodies in response to infection in -.

1920

Vacciners for diphtheria, tetanus, pertussis (whopping cough) & tuberculosis (BCG) were all available.

1930

·    Karl Landsteiner won the Nobel prize for the discovery of ABO antigens & antibodies.

·    He also coined the term “hapten”.

Karl Landsteiner

1930

who won the Nobel prize for the discovery of ABO antigens & antibodies.

·    He also coined the term “hapten”.

Karl Landsteiner

1930

who coined the term “hapten”.

1930

The search for the cells that produce the antibodies encouraged the study of cellular immunity.

429 BC

Thucydides noticed that smallpox survivors did not get re-infected

900 AD

Chinese inhaled smallpox scabs to produce protection from the then deadly dx, this was called variolation.

Chinese

900 AD

who inhaled smallpox scabs to produce protection from the then deadly dx, this was called variolation.

1717

Variolation reaches Turkey & the rest of Europe through the work of Lady Mary Wortley Montagu, poet & wife of the British ambassador to Turkey.

Lady Mary Wortley Montagu

1717

Variolation reaches Turkey & the rest of Europe through the work of -, poet & wife of the British ambassador to Turkey.

1876

·    Robert Koch isolated the anthrax virus & showed that it caused the dx.

1882

Robert Koch Isolated the causative agent of tuberculosis (-)

1891

when did Robert Koch explored delayed type hypersensitivity.

1883

Ellie Metchnikoff observed that foreign objects introduced into transparent starfish larvae became surrounded by motile cells that attempted to destroy these invaders. He called this phagocytosis, meaning “cells that eat cells”. He hypothesized that immunity was based on this function which was called cellular immunity.

Ellie Metchnikoff

phagocytosis

cellular immunity.

In 1883, who observed that foreign objects introduced into transparent starfish larvae became surrounded by motile cells that attempted to destroy these invaders. He called this - , meaning “cells that eat cells”. He hypothesized that immunity was based on this function which was called -

1890s

Emil von Behring demonstrated that diphtheria (with Wernicke) & tetanus toxin (with Kitasato) produced by microorganisms as they grow can be neutralized by the noncellular portion of blood of those previously infected. This was called humoral immunity.

Wernicke

Kitasato

humoral immunity.

Emil von Behring demonstrated that diphtheria (with -) & tetanus toxin (with -) produced by microorganisms as they grow can be neutralized by the noncellular portion of blood of those previously infected. This was called -

1896

·    Methods to detect the presence of antigens using serum (noncellular portion of the blood) were discovered.

·    Gruber & Durrham described bacterial agglutination.

·    Widal developed an agglutination test for typhoid fever shortly after.

·    Kraus later described precipitation.

Most serologic tests are based on agglutination & precipitation as end results of the tests.

  Gruber & Durrham

In 1896, who described bacterial agglutination.

Widal

In 1896, who developed an agglutination test for typhoid fever shortly after.

Kraus

In 1896, who later described precipitation.

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Most serologic tests are based on agglutination & precipitation as end results of the tests. (t/f)

1903

·    English physician Almroth Wright linked the 2 theories. He observed that certain humoral factors called “opsonins” acted to coat bacteria so that it would be more susceptible for phagocytosis.

Around this time, it was acknowledged that the serum factor was formed when an antigen is introduced. The serum factors were called “antibodies” which is also known as immunoglobulins.

Almroth Wright

In 1903, who linked the 2 theories. He observed that certain humoral factors called “opsonins” acted to coat bacteria so that it would be more susceptible for phagocytosis.

antibodies

immunoglobulins

In 1903, it was acknowledged that the serum factor was formed when an antigen is introduced. The serum factors were called “-” which is also known as -.

Leukocytes

1. N - Neutrophils / Polymorphonuclear Neutrophilic (PMN) Leukocyte

2. E - Eosinophils

3. B - Basophils

4. M - Monocytes / Macrophages

5. L - Lymphocytes

Cells of the Immune System

Neutrophils / Polymorphonuclear Neutrophilic (PMN) Leukocyte

Approximately 50 – 70% of total peripheral WBC

Neutrophils / Polymorphonuclear Neutrophilic (PMN) Leukocyte

Has a nucleus with 2 – 5 segments & cytoplasm filled with primary & secondary granules that contain enzymes & chemicals.

Neutrophils / Polymorphonuclear Neutrophilic (PMN) Leukocyte

Function

·   1^st responder to infection, phagocytosis

Neutrophils / Polymorphonuclear Neutrophilic (PMN) Leukocyte

Function

In the tissues they may wander randomly or be attracted to a specific area by chemotactic factors or chemotaxins.

Neutrophils / Polymorphonuclear Neutrophilic (PMN) Leukocyte

Eosinophils

-       Characterized by the presence of large granules within their cytoplasm that can be stained with a dye called eosin, which gives them their name.

Eosinophils

1 – 3% of circulating WBCs.

Eosinophils

·   Has bilobed nucleus & cytoplasm filled with orange-red granules that also contain certain enzymes.

Eosinophils

Less efficient phagocytes than PMNs (bc they are present in smaller numbers & they lack digestive enzymes)

Eosinophils

Function

·   Have an important role in neutralizing basophil & mast cell products.

Fc epsilon receptor (FcεR)

Function of Eosinophil

·   Helminths coated with IgE are recognized by eosinophils via -  & release major basic protein & eosinophil cationic protein.

Fc epsilon receptor (FcεR

Function of EosinophilsF

·   Helminths coated with IgE are recognized by eosinophils via -  & release major basic protein & eosinophil cationic protein.

Kill parasites, neutralize basophil & mast cell products, regulate mast cells

Eosinophils

Basophils

<1% of circulating WBCs.

Basophils

·   Contain coarse densely staining deep bluish-purple granules that often obscure the nucleus.

Basophils

Granules contain histamine (contracts smooth muscle), eosinophil chemotactic factor of anaphylaxis, & heparin (anticoagulant).

Basophils

Function

Induce & maintain allergic reactions, stimulates production of IgE.

Basophils

Monocytes / Macrophages

-       4 – 10% of circulating WBCs

Monocytes / Macrophages

-       Roam around lungs, liver & connected tx.

30 hrs

Monocytes stay in the peripheral blood for up to - hrs then migrates to the tx & become known as macrophages.

macrophages

Monocytes stay in the peripheral blood for up to 30 hrs then migrates to the tx & become known as -.

Monocytes / Macrophages

·   Largest cells in peripheral blood, 12 – 22 µm in diameter

12 – 22 µm

Monocytes is the largest cells in peripheral blood, - in diameter

Monocytes / Macrophages

·   Has an irregularly folded or horseshoe-shaped nucleus that occupies almost ½ of the entire cell’s volume.

irregularly folded or horseshoe-shaped nucleus

Monocytes has - nucleus that occupies almost ½ of the entire cell’s volume.

Monocytes / Macrophages

Cytoplasm stain dull-grayish blue & has a ground-glass appearance (fine dustlike granules)

dull-grayish blue

ground-glass appearance (fine dustlike granules)

Monocytes’ cytoplasm stain - & has a -

Alveolar cell

Monocytes / Macrophages location & names:

·   Lungs:

Microglial cell

Monocytes / Macrophages location & names:

·   Brain:

Mesangial cell

Monocytes / Macrophages location & names:

·   Kidney:

Kupffer cell

Monocytes / Macrophages location & names:

·   Liver:

Osteoclasts

Monocytes / Macrophages location & names:

·   Bone:

Histocyte

Monocytes / Macrophages location & names:

Connective Tx:

Lymphocytes

-       20 – 40% of circulating WBCs.

found in lymph nodes, spleen, other secondary lymphoid organs

Location of lymphocytes

Lymphocytes

·   Key mediators of adaptive immunity

Lymphocytes

·   Heterogenous in lineage, function, & phenotype & are capable of complex biologic responses & activities

F

·   Heterogenous in lineage, function, & phenotype & are capable of complex biologic responses & activities

Lymphocytes is homogenous in lineage, function, & phenotype & are capable of complex biologic responses & activities (t/f)

CD markers (clusters of differentiation).

All lymphocytes look the same but be identified by panels of monoclonal antibodies by the proteins they possess. These proteins are called -

1. T Cell

2. B Cell

3. NK Cell

Subtypes of Lymphocytes

T Cell

Subtypes of Lymphocytes

- – produce cytokines (cell mediated immunity) (differentiates in the thymus)

thymus

T cells differentiates in the -

B Cells

Subtypes of Lymphocytes

– produce antibody in adaptive immune response (humoral immunity)

Bone marrow

B cells is found in

NK Cells

Subtypes of Lymphocytes

– involved in innate immunity(found mainly in the liver, spleen & peripheral blood)

1. Macrophages

2. Mast Cells

3. Dendritic Cells

Tissue Cells

·   Lungs

·   Liver

·   Brain

·   Bone

·   CT

Other tx

Locations of Macrophages