Pathophysiology: Immunity

Briefly define monoclonal antibodies.

Identical antibodies produced in response to a single antigen from clones of a single parent cell.

What are the two distinct responses of the immune system?

Innate and Adaptive

What is the normal white blood cell count?

4,000-11,000

Describe neutrophils

Bodies first line of defense against bacterial infections

IgM

First antibody to be produced during antigen and/or antibody response. It is effective against microbes and activates the complement chain

IgE

Involved in allergic response. found in blood and located on mast cells and basophils.

Why would it be dangerous to give live vaccines to a pregnant woman?

It could harm the woman due to the fact that the baby is compromising her immunity

What two types of cells are mainly responsible for phagocytosis?

Neutrophils and Macrophages

Identify types of cells of the immune system and their origins.

Neutrophils: bone marrow Basophils & Mast cells: bone marrow Esinophils: bone marrow Monocytes (Macrophages): bone marrow Natural Killer (NK) Cells: bone marrow Red Blood Cells (RBCs): bone marrow T & B Cells: Bone marrow

Identify physical, chemical, and mechanical barriers to infection.

Physical: epithelial cells of the skin an linings of the GI and genitourinary, and respiratory tracts. Mechanical: sloughing off a skin cells, coughing or sneezing, vomiting, and urination. Chemical: secretions like mucous, perspiration, saliva, breast milk, tears, and earwax

What is the concern regarding women with autoimmune disease and pregnancy?

Pregnant women with an autoimmune disease are more likely to produce antigens that will attack the fetus, increasing the risk for spontaneous abortion

Eosinophils

Reduce the inflammatory response, for Ex: by producing enzymes that destroy histamines

Briefly explain the complement system.

System of plasma proteins (C1 to C9) which take part in a cascade of reactions to generate active components. these attract white cells, coat pathogens and form a membrane attack system, which splits open foreign cells.

Lymphocytes

T & B cells are vital for specific immunity and the production of the antibodies, and null cells, including NK cells

Briefly explain the process of the binding of an antibody to an antigen.

The antibody has 2 binding sites for specific antigen that they attach to when they come in close contact and recognize that specific part of the antigen.

What are the functions of the immune system?

To monitor, recognize, respond to and cease immune activity. The immune system monitors the body's internal environment for the presence of any pathogen or any changes in cells that may result in tumor formation.

What is agammaglobulinemia? And what is the outcome?

a lack of gamma globulin in the blood plasma, causing immune deficiency.

Describe the reticuloendothelial system and its function.

a network of macrophages, associated wit lymphocytes, found in connective tissues, bone marrow, lymph nodes, the spleen, the liver, the brain, and the lungs. Functions include filtering out and destroy other particles and dead cells, and identifying foreign substances.

chemotaxis

a process by which the release of chemicals attracts defense cells

What is Severe Combined Immunodeficiency?

a severe defect in both the T- & B-lymphocyte systems

T-Cells

a type of lymphocyte that play a central role in cell-mediated immunity.

What is C reactive protein and why do we measure it?

an acute-phase protein, which activates monocytes and is a useful marker of inflammation, injury, or infection.

What are opsonins?

an antibody or other substance that binds to foreign microorganisms or cells, making them more susceptible to phagocytosis.

What is cell mediated immunity?

an immune response that does not involve antibodies, but rather involves the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen.

Explain antigen-antibody complexes.

antibodies bind antigens by a lock and key mechanism to produce antigen/antibody complexes. These are a key feature of the specific immune system, which stimulates the non-specific system and inflammation.

T helper cells

are able to activate the adaptive immune response, increasing its rate and intensity, and boosting the effectiveness of the innate immune response.

What is an autoimmune disorder?

arise from an abnormal immune response of the body against substances and tissues normally present in the body.

How long is an infant protected by maternal antibodies?

first 2-3 month of life

IgD

helps activate B cells. Found in lymph and blood

IgA

helps fight allergies and is secreted in tears, saliva, mucous, protects lungs, GI tract, genitalia, also secreted in colostrum. Provides protection on mucous membranes

What are antibodies?

highly specific protein secreted by B lymphocytes following exposure to an antigen

What are lymphokines?

hormones that regulate the immune response.

Differentiate active, passive types of acquired immunity.

immunity arising from exposure to antigens & transfer of antibodies from one individual to another Ex: Mother to child

Monocytes: (macrophages)

ingest foreign material, immune regulation, and wound-healing

Name the four main anitmicrobial substances.

interferons, complement, iron-binding proteins, and antimicrobial proteins

Thymus gland

involved in the selection of the lymphocytes that will go on to help defend us against infection while protecting us from lymphocytes that could potentially attack our own organs (autoimmune disease)

What are the roles of the thymus gland?

involved in the selection of the lymphocytes that will go on to help defend us against infection while protecting us from lymphocytes that could potentially attack our own organs (autoimmune disease).

What are the main functions of T cells?

kill body cells that have become infect with pathogens and are therefore inaccessible to antibodies, maintain an inflammatory response at the site of persistent infection, and regulate many features of acquired and innate immune responses.

Basophils

mediate hypersensitivity reactions of the immune system

IgG

most common, enhances phagocytosis, neutralizes toxins and protects against bacteria and viruses.

What happens with the primary immune response (first exposure)? the secondary immune response (second or subsequent exposure)? What are the implications of these?

occurs when immune cells encounter an antigen for the first time. This is mainly mediated by IgM antibodies. IgM antibodies proliferate and make plasma cells and memory cells so they may "remember" if they ever encounter that same antigen again. Exposure to the same antigen again elicits secondary immune response. In contrast to above process secondary response has few IgM antibodies but it is mainly mediated by IgG antibodies.

Discuss B cells as plasma cells and memory cells.

play a role in antibody-mediated immunity and secrete antibodies necessary to fight infections. Come from the secondary immune system and have an affinity for a specific antigen that can last years.

B-Cells

produce antibodies

What is hypersensitivity?

refers to undesirable reactions produced by the normal immune system, including allergies and autoimmunity. These reactions may be damaging, uncomfortable, or occasionally fatal

What are inflammatory mediators?

soluble, diffusible molecules that act locally at the site of tissue damage and infection, and at more distant sites. They can be divided into exogenous and endogenous mediators.

What is adaptive immunity?

specific immune response. The antigen must be processed and recognized, then the adaptive immunity creates an army of immune cells designed specifically to attack that antigen

What is an antigen?

substances that can stimulate an immune response

What is Humoral immunity?

the aspect of immunity that is found in ECF and is mediated by antibodies, complement proteins and certain antimicrobial peptides.

margination

the process in which free-flowing leukocytes exit the central blood stream, and initiate leukocyte and endothelial cell interactions by close mechanical contact.

Primary lymphoid tissues

the thymus and the bone marrow

Cytotoxic T-cells

use toxic and perforin chemicals to kill the body's cells when they become infected with intracellular pathogens