Nonspecific Immunity

Provides immediate non-specifc response to pathogens

Adaptive immunity

creates immunological memory after initial responses to a specific pathogen. Responses are quicker & more intense

Major histocompatibility complex

a group of cell surface molecules which allows the ability to distinguish self from non-self

Epitope

specific region on antigen that T-Lymphocytes bind to

Antibody-mediated immunity

B cell production of antibodies which facilitate phagocytosis

Cytokines

factors that mediate communication between cells involved in immune response

List some of the body’s nonspecific defenses

Anatomical barriers like acidic secretions such as organic, gastric and bile acids

flushing actions such as sweating, tears, saliva, mucous, cilia hairs, escalator and peristalsis which remove potentially harmful bacteria

microbiome which helps prevent bacterial colonization

inflammatory response, fever and ongoing phagocytosis

Describe the key features of adaptive immunity

¹Specificity [responds to specific substances]

²Recognition [recognizes microorganisms]

³Learning [pathogen is remembered once encountered]

⁴Memory

⁵Self-recognition

What are major histocompatibility complex (MHC) proteins

MHC proteins, once displayed, are essentially just antigens.

What are the differences between Class I MHC and Class II MHC proteins?

class one: located in all cells and help immune system recognize an infected cell.

class two: proteins are only found in phagocytes and allow immune system to recognize and destroy foreign antigens.

class two: cells become APCs.

Describe the structure and/or function of cytotoxic T cells, helper T cells, suppressor T cells, and B cells.

¹Cytoxic T Cells (Class I) attack & destroy infected and abnormal cells displaying antigens.

²Helper T Cells (Class II) stimulate immune response by T cells and B cells.

³Suppressor T Cells (Class I) control or moderate immune response by T cells and B cells.

⁴B Cells are responsible for antibody-mediated immunity and are produced and matured in bone marrow. They also form specific antibodies and are studded with antibodies.

What is an antibody and what is its purpose

Antibodies are y-shaped proteins that link WBCs to pathogens.

Antibodies consists of 2 F_ABs and 1 F_c and are specific to their antigen.

The F_AB arms are the binding sites for the antigen. 

¹IgG: the major antibody in the body. It binds to macrophages, is the only one to cross placenta and bind to microphage. Makes up 75% of antibodies. 

²IgA: this is an antibody found most of the times in secretions. It can be found in saliva, breast milk, respiratory and urogenital secretions. It also protects mucous membranes and only makes up 15% of antibodies.

³IgM: this antibody is prominent in early immune response and forms natural antibody ABO blood groups. It only makes up 10% of antibodies.

⁴IgD: this antibody is an antigen receptor on the B cell membrane and only makes up 0.2% of all antibodies.

⁵IgE: this antibody is the lowest IgE and takes up only 0.004% of all antibodies. They bind to mast cells and basophils and are involved in parasitic infections, allergies, and hypersensitivity reactions.

Compare immunodeficiency disorders, hypersensitivity reactions, and autoimmune diseases.

¹All are abnormalities

²ID & HR both have some form of subtype. ID has Primary [genetic] & Secondary [malnutrition, HIV, cancer or medication], while HR has ¹Immediate hypersensitivity (Type I), ²Antibody-mediated (Type II), ³Immune complex-mediated (Type III) and Cell-mediated (Type IV)

contrast immunodeficiency disorders, hypersensitivity reactions, and autoimmune diseases.

ID has increase paranoia to disease caused by some type of deficiency while HR is an immune response on steroids [excessive], while AD confuses the immune system to fight against its body’s own tissues. 

¹Immediate Hypersensitivity TYPE I

²Antibody-Mediated TYPE II

³Immune Complex-mediated TYPE III

⁴Cell-Mediated TYPE IV

an anaphylactic reaction which means it is an exaggerated allergic reaction to a foreign protein resulting from previous exposure to it. Its mediated by the IgE antibody, basophils and mast cells and some examples include hay fever, asthma and food allergies. 

²Antibody-Mediated TYPE II

This is mediated by IgM & IgG antibodies in which the antibodies attach to the host cells. Some examples include Grave’s disease, Myasthenia gravis and Erythroblastosis fetalis.

³Immune Complex-mediated TYPE III

⁴Cell-Mediated TYPE IV