A foreign substance to the body that triggers an immune response-

Antigen

Which of the following are characteristics of innate immunity?

Inflammation, Fast Response, Cytokine production

T cells of the immune system include-

helper T cells (CD4+) and cytotoxic T cells (CD8+)

Another term for white blood cells is?

Leukocytes

Leukocytes migrate to a site of infection in response to-

Chemokines

The first line of defense against microorganisms that infect the body is referred to as _____.

Innate Immunity

What are examples of a physical immune response?

skin, mucus

Innate immunity is ___________ and activated within hours of exposure to a pathogen. While adaptive immunity is ____________ and responds several days after initial exposure,

non-specific, specific

Which antibody is involved in allergies and parasitic infections?

IgE

Which antibody is expressed in mucosal tissues and forms dimers after secretion?

IgA

Which antibody is produced by B-cells as the first line of defense against antigen invasion?

IgM

Which antibody is the most common and is important for the secondary immune response?

IgG

The function of IgG1 is to -

neutralizes viruses, activates complement, and promotes antibody-dependent cell cytotoxicity.

IgG2 is mainly effective against-

bacterial infections

IgG3 fights ________ infectstion and activates complement.

viral

IgG4 is associated with -

allergic reactions

The Th1 effector cell is responsible for -

anti-viral and anti microbial immunity

What effector cell has this function?

"clearance of extracellular pathogens (fungi, bacteria)"

Th17

Which effector cell has immunity against extracellular parasites, allergens, and toxins?

Th2

What is the function of the effector cell pTreg?

tolerance against enviornmental antigens and microbiota.

What is the function of the effector cell eTreg?

tolerance against self-antigens (autoimmunity).

TLR cytokines

IL, TNF, IFN, TGF

What is an IL (interleukin) cytokine?

acts as a signaling protein to regulate the immune system

TNF is a-

A pro-inflammatory cytokine produced by immune cells. Important for regulating immune response and inflammation.

IFN (interferon) cytokine does-

signals molecules to modulate immune response, more specifically against viral infections.

What cytokine regulates cell growth, differentiation, and plays an important role in immunity, development, and disease?

TGF

Antigenic variation allows pathogens to -

escape from immunity

Some viruses persist ____________ by ceasinfg to replicate until immunity wanes

in vivo

What can contribute to persistent disease?

Immunosuppression or inappropriate immune response.

What is the result of T-cell defects?

low antibody levels

Defective humoral immune function is caused by defects in _____________ ______________.

complement components

Defects in phagocytic cells permit -

widespread, chronic bacterial infections

HIV is a retrovirus that infects what cells?

CD4 T-cells, dendritic cells, and macrophages.

HIV RNA is transcribed by-

reverse transcriptase.

Why are the low levels of CD4 T cells caused by HIV dangerous?

It can cause increased susceptibility to opportunistic infection, which can lead to death.

A type I reaction is-

IgE-Mediated Hypersensitivity.

What occurs in a Type I Hypersensitivity reaction?

An immediate allergic reaction in response to an allergen. Antibodies trigger mast cells to release histamine and other mediators.

A type II reaction is-

IgG-Mediated Cytotoxic Hypersensitivity.

A type III reaction is-

Immune Complex Mediated Hypersensitivity.

A type IV reaction is-

Cell-Mediated Hypersensitivity.

What occurs in a Type II Hypersensitivity?

antibodies (IgG or IgM) bind to cells/tissues, causing damage through complement activation or other immune responses. (autoimmune)

What occurs in a Type III Hypersensitivity?

Deposition of soluble immune complexes (antigen-antibody aggregates) in tissues. Inflammation and tissue damage occur by attracting neutrophils and activating complement.

What occurs in a Type IV hypersensitivity?

T-cell-mediated immune response that occurs 48-72 hours after exposure. Contact dermatitis, drug reactions, and transplant rejection can be caused. T-cells recognize an antigen, destroy healthy cells, and trigger inflammation via cytokines.

Phagocytes-

A general term describing white blood cells that engulf and digest foreign pathogens in a process called phagocytosis. Neutrophils and macrophages are phagocytes.

Granulocytes-

The general term describing white blood cells that are granulated (neutrophils, basophils, and eosinophils).

Macrophages-

Macrophages are found in the body tissues. They are large phagocytic cells that become powerful stimulators of an immune response when they engulf a pathogen.

Monocytes-

They become macrophages.

Neutrophils-

kills, communicates, and causes inflammation.

What does complement do?

mark and cripple enemies, activate and guide immune cells.

Dendritic cells-

Identify enemies and activate other cells.

Eosinophils and Basophils both-

cause inflammation, battle parasites, and activate other cells.

(True or False) A virgin killer T cell is in a standby mode and can become a killer T cell.

True

Killer T cells attack what kind of cells?

infected/cancer cells

A ________ T cell communicates and activates other cells.

helper

A B cell produces __________

antibodies

The function of antibodies is to-

mark and disable enemies, and to activate complement.