MLT 115 Mod 2 Lymphocytes Pt 1

These flashcards cover the foundational concepts in serology, focusing on the immune response, lymphoid tissues, and their functions.

What are the two types of lymphoid tissues in the spleen?

Red pulp and white pulp.

What immune response do Peyer's patches in the small intestine initiate?

They release IgA to attack ingested antigens.

What happens when there is excessive lymph node production?

It can lead to Hodgkin's lymphoma.

What substance is secreted by T cytotoxic cells that helps in immune response?

Lymphokines.

What are interferons?

They are cells with antiviral and antitumor properties.

What is the significance of T lymphocytes in the blood?

80% of T lymphocytes are found in peripheral blood and are crucial for the immune response.

What does lymphadenopathy mean?

Swollen lymph nodes.

What is the thoracic duct?

A major lymphatic vessel that collects lymph from the body and transports it to the bloodstream.

What are the major types of granulocytes and monocytes?

They include segmented neutrophils, basophils, eosinophils, and monocytes.

What are the components of Primary Lymphoid Tissue?

Bone marrow and thymus.

How does the thymus change over a person's life?

It is highly active in children but diminishes in size and activity with age.

What structures make up Secondary Lymphoid Tissue (6 structures)?

Adenoids, appendix, lymph nodes, peyer’s patches, spleen and tonsils.

What are Peyer's patches and where are they found?

A part of the GALT, they are clumps of lymphoid tissue located in the small intestine.

Where are lymph nodes frequently located in the human body?

Cervical (neck), axillary (armpit), inguinal (groin), and mediastinal (sternum) areas.

What is lymphadenopathy?

Enlarged lymph nodes caused by immune response activation, commonly called "swollen glands."

What are the two main tissue types in the spleen and their functions?

Red pulp removes worn-out red blood cells, and white pulp stores lymphocytes and immune cells.

What is GALT and what are the 3 immunological roles it plays?

Gut-Associated Lymphoid Tissue; it produces IgA, allows lymphocyte recirculation, and helps determine tolerance to food antigens (using IgE during allergic reactions).

What is the significance of the Thoracic Duct?

It is a great source of T lymphocytes and serves as the main channel for circulating lymph fluids.

What is BALT and where is it precisely located?

Bronchus-Associated Lymphoid Tissue; it is found around the respiratory tract, specifically the trachea and bronchial tubes.

What cancer is associated with a loss of control in B lymphocytes within BALT?

Hodgkin's Lymphoma.

What is SALT and how does it function?

Skin-Associated Lymphoid Tissue; they are bone-marrow derived cells that fight pathogens at the skin level (e.g., responding to Poison Ivy).

What is the distribution of T-lymphs between peripheral blood and lymph nodes?

80% of T-lymphs are in peripheral blood, while 20% are stored in lymph nodes.

What causes Graft vs. Host Disease?

It occurs when incompatible transplanted T cells from a donor attack the recipient's tissues due to circulation between lymph nodes and blood.

What is the difference between Afferent and Efferent lymphatic vessels?

Afferent vessels lead into the lymph nodes, while Efferent vessels lead out.

What are mast cells and where are they commonly located?

They are tissue basophils found particularly in the lungs that cause collagen reactions.

What is the typical life span of T lymphocytes compared to B lymphocytes?

T lymphocytes can live for months or years, whereas B lymphocytes usually survive for only a few days.

How are T Helper Cells ($T_{h}$) subdivided functionality?

They are divided into T1 (cell-mediated immunity) and T2 (antigen presentation).

What are the functions of T Cytotoxic Cells?

They directly kill infected or malignant cells, release lymphokines, and secrete interferons.

What is the role of T Regulator/Suppressor Cells?

They control the immune response by turning off T helper and T cytotoxic cells once the threat is neutralized.

What are lymphokines?

They are cytokines and chemical messengers secreted by Cytotoxic T cells that act on antigens.

How long does it take for T lymphocytes to mature?

3 weeks