Normal Immunology

8/3/2019 Normal Immunology

1/29

NORMAL IMMUNOLOGY


2/29

Overall Characteristics of the Specific Immune System

Response (5 Cardinal Features)

Self/ Not Self Tolerance A unique feature of the immune system.

Discrimination of self from not- self is the recursiveability of the immune cells to engage in the processof exploring the cellular environment.

Healthy cells are left alone, and the immune cells

identify and mount responses against foreign cells aswell as cancerous or infected self- cells.

Example of error- free self- identification that leadsto self tolerance: maturation process of T Cells.

Self- regulation

The ability of the immune system to initiate,maintain, and down regulate immune activityindependent of the nervous system or othercontrols.


3/29

Overall Characteristics of the Specific Immune

System Response (5 Cardinal Features) Specificity

The ability of the immune system to design and implement asimmune response that is targeted only to a single, specificantigen or foreign cell.

Diversity The body has an ability to develop a specific response to an

indefinite number of different antigens. The human genetic repertoire provides us with an ability to

mount a specific response to about 10, 000 different antigens.

Memory

Once the immune system identifies antigen and mounts animmune response, it can store a memory of antigen and keep

memory cells available throughout the life span to provide aprompter response to secondary exposure


4/29

The Immune System

1. Central Lymphoid Organs

Bone Marrow It contains the parent or stem cells from which lymphoid cells are

derived.

Red marrow- provides all of the blood cells in the body.

Yellow marrow- stores lipids, serving as an energy reserve.

Immature T lymphocytes are formed in the bone marrow.

The originating cells (prulipotent hematopoietic stem cells) produce: All the circulating blood cells

Lymphoid and myeloid cells (WBC)s Erythrocytes (RBCs)

Thrombocytes (platelets)


5/29

Thymus Gland

A primary lymphoid gland located in the mediastinal area of the chest.

It weighs about 20 gm. At birth, grows rapidly in children, and reaches a maximum size

at puberty (about 35 gm.), after which it gradually begins the process of involution.

The thymus processes and matures lymphocytes in large numbers from the early years

of life until puberty at diminishing rates throughout adult life.

Lymphocyte maturation is the process of transformation of lymphocyte precursor cellsinto antigen- specific lymphocytes regulated only to respond to specific antigens under

proper conditions of antigen recognition.

Bone marrow produces immature immune cells

Immature cells travels via the blood

Cells reaches the cortex of thymus

Maturation and development

Reaches the medullary area of the thymus

Lymphocytes become differentiated and transforms into immunocompetent cells.

Cells enters the circulation.

Identifies and reacts to foreign tissues.


6/29

Bone marrow produces immature immune cells

Immature cells travels via the blood

Cells reaches the cortex of thymus

Maturation and development

Reaches the medullary area of the thymus

Lymphocytes become differentiated and transforms into immunocompetent cells.

Cells enters the circulation.

Identifies and reacts to foreign tissues.


7/29

. Peripheral Lymphoid Organs and

Tissues

Lymph Nodes Are encapsulated secondary lymphoid organs that

systematically distributed throughout the body to receive

and process the lymph circulation. Mucosa- Associated Lymphoid Tissue (MALT)

Aggregates of lymphoid tissue that are found in manyorgans specially the GI and respiratory tracts.

Gut- associated lymphoid tissues (GALT)

Lymph node- like tissues in the GI tract that collect antigen fromepithelial surfaces in the lumen of the bowel.

The lymphocytes form a follicle that protrudes within the lumen toenhance potential contact with antigen entering the GI tract.

Include: tonsils, adenoids, vermiform appendix, and Payer's patches.


8/29

Peripheral Lymphoid Organs and

Tissues

Bronchial- associated lymphoid tissue (BALT)

It has specificity for airborne pathogens.

It is facilitated by the flow of mucus out of the lungs through

the ciliary action of the columnar epithelial cells and the

cough reflex.


9/29

Peripheral Lymphoid

Organs and Tissues

Spleen

The largest internal lymphatic organ, weighing about180 to 240 gm.

It can function as a reservoir for blood in its venoussinuses and pulp.

It also processes RBCs that squeeze through its pores.

Phagocytic cells, especially macrophages, line the

pulp and sinuses of the spleen. These cellsfunction in the process of immunity to clearblood- borne pathogens


10/29

Peripheral Lymphoid Organs and

Tissues Structural and Physiologic Barriers in Bodily Defense

Physical barriers

Intact skin Primary barrier to entry into the body.

The tight junctions of the skin in the skin, the presence of antibacterialpeptides, and the shedding property of surface cells in the skin makes itdifficult for pathogens to colonize or enter.

The Mucous membranes Serve as physical barriers to invasion because of cellular alignment, ciliated

epithelial functions, longitudinal flow over their surfaces, the movement ofmucus, the presence of microbeactive enzymes, various pH levels, and fattyacids.

Saliva

Tears

Urine flow


11/29

Peripheral Lymphoid

Organs and Tissues Physiologic Barriers

Acidic pH A barrier to pH- sensitive pathogens.

Soluble factors in tissue and tissue secretions

Many chemicals are bacterially active and function throughenzymatic reactions.

High tissue or body temperature A defensive mechanism against temperature- sensitive

pathogens.

Commensal organisms in the GI tract Serve to regulate pH, available pathogen food supply, and

available binding sites and access points for microbial invasion.


12/29

Peripheral Lymphoid

Organs and Tissues . Cells of the Immune System

Cells of Innate, Non- specific Immunity

It includes the interaction of phagocytes with antigen as well as chemical mediators from other WBCs.

Macrophages The mature cells of the mononuclear phagocyte system (or monocyte- macrophage system).

They function in phagocytosis of antigen and in processing and presenting antigen to specific

lymphocytes. They serve an essential function in removing foreign and devitalized mineral from the body.

They trap and process antigens to present them to specialized lyphocytes.

Neutrophils The most numerous and the most important cellular component of the innate, non- specific immune

response.

They serve to complete the phagocytic family of cells and a first-line defender in the body againstbacterial invasion, colonization and infection.

Eosinophils They are believed to play a pivotal role in defense against parasitic infections. They are components of

innate immunity but can be activated by lymphocytes, and serve an adapted immunity

Basophils They play a role in protecting mucosal surfaces throughout the body, and, like mast cells, they release

substances that assist other cells in the inflammatory response.

Mast Cells Derived from bone marrow cells that are distinct from basophils.

They serve to provide substances that are supportive and enhancing of immune responses.


13/29

Peripheral Lymphoid

Organs and Tissues Cells of Adaptive, Specific Immunity

They are essential for producing immunity to disease and protectionfrom other foreign agents.

B Lymphocytes

Are responsible for humoral immunity or immunoglobulin- mediated immunity, which isspecific immunity for antigens that are found outside of the host cells.

They originate in the bone marrow and mature either there or in some other site.

They are capable of proliferating and differentiating into plasma cells and memory cellswhen exposed into a specific antigen.

Plasma cells- capable of secreting large quantities of specific immunoglobulin, theimmune active portion of humoral immunity. Immunoglobulin secreted by plasmacells is called antibody.

Memory cells- serve the purpose of stockpiling a specific clone of B cells, so that

immediate production of large quantities of the specific immunoglobulins resultswhen the cells are next exposed to a particular antigen.


14/29

Immunoglobulins

1IgG- makes up about 75% of the antibodies normally circulating in plasma.

IgG has been shown to carry the major burden in neutralizing bacterial toxins.

This function is essential in accelerating the process of phagocytosis.

2IgA- most of IgA is in the form of secretory IgA in the external body secretions

such as saliva, sweat, tears, bile, and colustrum. It provides a defense against

pathogens on exposed surfaces of the body, especially those entering the

respiratory and GI tract.

3IgM- Often called the macroglobulin (because it is the largest). It is the first

immunoglobulin produced in quantity during an immune response, and so rise

early in the course of infection. It is efficient in agglutinating antigen, fixing

complement, and lysing cell walls.

4IgD- is present in plasma in very low concentration and is readily broken down.Its exact function is not well understood, but its presence on lymphocyte surfaces

together with IgM suggests that it may be a receptor that helps find antigens to

the cell surfaces. Its levels are elevated in chronic infections.

5IgE- serves to activate mast cells. It is normally fixed on tissue surfaces.


15/29

Cells of Adaptive, Specific Immunity

T Lymphocytes They account for about 75% of the serum lymphocytes. They

originate from stem cells in the bone marrow but are matured inthe thymus gland and are sometimes called thymocytes.

They can be functionally divided into three subgroups: Helper T Cells- stimulates B Lymphocytes to differentiate into

antibody producers and serve to activate cytotoxic Tlymphocytes and other T cell responses; they are thereforeresponsible for activating the specific immune response.

Killer T Lymphocytes- bind to the surface of the infected cells,disrupt its membranes, and kill it by altering intracellular

environment. Suppressor T Cells- reduce the humoral response. The

production of immunoglobulins against a particular antigencan be reduced or abolished in the presence of these cells.


16/29

Types of Immunity

Innate (Natural) Immunity Refers to those factors a person is born with to prevent disease.

These can either be: physical barriers (skin, mucous membranes, cough etc.)

Chemical barriers

Internal factors (mononuclear phagocytes and leukocytes)

Acquired Immunity Refers to passive and active immune process.

Passive active immunity- occurs in early neonatal life, when some of the mothersimmunity, which was passed through the placenta prenatally, continues to protect theinfant from the disease. It protects for the first few months of life.

Acquired active immunity- involves the response mounted by the persons immune

system. Scientists have discovered the process of inducing acquired immunity throughvaccination.


17/29

Types of Immunity

Adaptive Immunity It is responsible for the protection of the human body from the disease. It

requires a cellular and/or humoral response to an antigen.

This type of immunity is an active process of specifics recognition of antigenand the production of a bank of cells that remember the antigen and quicklyrespond to repeat antigen introduction.

Cell- mediated Immunity Is mediated through contact between T cells and antigen and by cystokines.

The interaction sets off a complex series of steps leading to subsequentdestruction of the antigen.

Stages of the Immune Response (Please see attachment)

I. Recognition Stage II. Prilifiration Stage

Response Stage

Effector Stage


18/29

INTEGRATION OF THE NURSING PROCESS

I. ASSESSMENT: Identifying modifiable risks based on:

Health History Age

People at the extremes of the lifespan are more likely to developproblems related to immune system functioning than are those inmiddle years.

Nutrition

Adequate nutrition is essential for optimal functioning of the immunesystem.

Vitamins: Essential for DNA and protein synthesis, if inadequate, may lead to protein-

calorie deficiency and subsequently to impaired immune function.

Also help in the regulation of cell proliferation and maturation of immunecells.

Fatty acids: the building blocks that that make up the structuralcomponent s of cell membrane.

Depletion of protein reserves results in atrophy of lymphoid tissue,depression of antibody response, reduction in the number of circulatingT cells, and impaired phagocytic function.


19/29

INTEGRATION OF THE NURSING

PROCESS Infection and Immunity

Immunizations received recently and those in childhood and the usualchildhood disease.

Known past or present exposure to tuberculosis.

A history of past and present infections and the dates and types of treatmentsthat were used, along with a history of any multiple persistent infections, FUO,

lesions or pores, or any type of drainage, are obtained. Allergy

History of any allergy and types of allergens: Pollens

Dust

Plants

Cosmetics

Food

Medications

Vaccines etc.

Symptoms experienced

History of testing and treatment


20/29

Disorders and Diseases

Autoimmune disorders:

More common in females Believed to be the result of the activity of the sex hormones.

Lupus erythematosus

Rheumatoid arthritis

Psoriasis

Neoplastic Disease

Any history of cancer, its type and date of diagnosis.

Dates and results of any cancer screening tests. All treatments that the patient has received or is currently

receiving, such as radiation or chemotherapy.

Family History of cancer


21/29

Disorders

and Diseases Chronic Illness and Surgery

History of Chronic Illness: DM

Renal diseases

COPD

History of surgical removal of: Spleen

Lymph nodes

Thymus

History of organtransplantation

Special problems Burns and other forms of injury

and infection

Physiologic and Psychologicalstressors

Medications and BloodTransfusions

Large doses of:

Antibiotics

Corticosteroids

Cytotoxic agents

Salicylates

NSAID

Anesthetics Single or multiple blood

transfusions


22/29

Disorders and Diseases

Lifestyle and other factors

Smoking

Alcohol consumption

Dietary intake

Nutritional status

Amount of perceived stress

Occupational or residential exposure to radiation and

pollutants

Physical Examination (Indications of


23/29


Immune Dysfunction)

Skin Lesions

Dermatitis

Purpura

Urticaria

Inflammation

Any Discharge

Temperature is recorded Note chills and sweating

Posterior cervical, axillary, and inguinal lymph nodes are

palpated Location Size

Consistency

Tenderness


24/29


Immune Dysfunction

Joints

Tenderness

Swelling

Limited ROM

Respiratory System Changes in RR

Cough

Abnormal lung

sounds Rhinitis

Hyperventilation

Bronchospasm

CardiovascularSystem Hypotension

Tachycardia

Dysrhythmia

Vasculitis Anemia

GastrointestinalSystem Hepatosplenomegaly

Colitis

Vomiting

Diarrhea


25/29


Immune Dysfunction

Genitourinary system

Frequency and burning on urination

Hematuria

Discharge

Neurosensory Cognitive dysfunction

Hearing loss

Visual changes

Headaches and migraines Ataxia

Tetany

Selected Tests for Evaluating


26/29


Immunologic Status

Leukocytes and Lymphocyte Tests

WBC Count and differential

Bone marrow high

Humoral (Antibody- mediated) Immunity Tests B- cell quantification with monoclonar antibody

In vivo immunoglobulin synthesis with T- cells subsets

Specific antibody response

Total serum globulins and individual immunoglobulins Phagocytic Cell Function Tests

Nitroblue tetrazolium reductase assay


27/29


Immunologic Status Complement Component Tests

Total serum hemolytic complement

Individual complement component titrations

Radial immunodiffusion

Electroimmunoassay Radioimmunoassay

Immunophlelometric assay

Immunoelectrophoresis

Hypersensetivity Tests Scratch test Patch test

Intradermal test

Radioallergosorbent test (RAST)


28/29

PLANNING AND IMPLEMENTATION

Maintenance and Promotion of Normal

Immune System Response

Dietary/ nutritional instruction

Vaccination/ Immunization


29/29

PLANNING AND IMPLEMENTATION

Prevention Against Microbial Invasion

Aseptic Techniques

Universal Precaution

Normal Immunology

Documents

Transcript of Normal Immunology