IMMUNOLOGY EXAM 4/12/26

Adaptive (Specific) Immunity

components that ADAPT over time and protect against SPECIFIC pathogens

Adaptive immunity is considered a _______ with two components.

dual system

Cell-Mediated Immunity

targets & destroys intracellular (inside host cells) pathogens using T cells

T cells use ___________ to generate an immune response.

TCRs

Humoral Immunity

targets & destroys extracellular (outside host cell) pathogens using B cells and antibodies

Cytotoxic T cells are primarily involved in _________

cell-mediated immunity

The humoral response is initiated by production of:

antibodies

What are primary lymphoid organs?

organs where immature T & B lymphocytes mature into NAIVE (inactive) forms

List the primary lymphoid organs

thymus, bone marrow

Thymus

where T cells develop

Bone marrow

where B cells develop

Both T & B lymphocytes are produced in bone marrow, but T cells _______________.

migrate to the thymus to fully develop

Secondary Lymphoid Organs:

organs where naive T & B lymphocytes are ACTIVATED & begin immune functions

List the secondary lymphoid organs:

lymph nodes, spleen, and tonsils

Secondary lymphoid organs description:

Sites where foreign molecules (antigens) are brought into contact with populations of lymphocytes

T cells and B cells are produced in the:

Bone marrow

T cells mature in the ______ & B-cells mature in the _______.

Thymus; Bone marrow

The secondary lymphoid organs are

where foreign antigens interact with lymphocytes

Which of the following are two of the secondary lymphoid organs?

Spleen & lymph nodes

What major advantage is conveyed by having a system of adaptive immunity?

It enables a rapid defense against an antigen that has been previously encountered.

Adaptive immunity (cell-mediated & humoral) generates immune responses toward foreign ________ in the body

antigens

Antigens

Molecules reacting specifically with T cells, B cells, or antibodies (derived from ANTIbody GENerator)

Antigens

differ in effectiveness to elicit an immune response (small antigens not immunogenic)

Immunogenic Antigens:

Any antigen that causes a strong immune response

Epitopes:

Distinct regions that B cell & T cell receptors or antibodies directly bind to

Epitopes:

A portion of antigen recognized by antibody

B cells only respond to ______ antigens (antigens NOT presented by a host cell).

free

T cells only respond to antigens that are ________ on antigens presenting cells.

presented

APCs:

specific immune cells that process & present antigens for T cell activation

List of APCs:

dendritic cells, macrophages, b cells

Many phagocytic immune cells such as macrophages and dendritic cells commonly engulf foreign or dangerous materials in the body. If these cells engulf antigens, the cells will present the antigens on their surface. Which immune cells will respond to these “presented” antigens and trigger an immune response if necessary?

T cells

Cell-Mediated Immunity

adaptive immunity that targets & destroys intracellular pathogens using T cells

Which of the following answers is a major difference between cell-mediated and humoral immunity?

• Cell-mediated immunity utilizes T cells while humoral immunity utilizes B cells to respond to infection

• Cell-mediated immunity involves antigens presented on APCs while humoral immunity involves free antigens

T-Cells:

Have thousands of IDENTICAL T-Cell receptors embedded in their membrane

TCRs

receptors allowing T-cells to recognize and “attack” specific intracellular pathogens

Each TCR consists of 2 polypeptide (alpha & beta chains) linked via DISULFIDE bonds and contain ______ different regions.

2

Variable Region

region that varies between different TCRs & directly bind the PRESENTED antigen

In the variable region:

amino acid sequence VARIATION accounts for the many different types of antigens different TCRs bind

Constant Region