L2 Architecture of I.S, T&B cells

Question 1

Name the acquired/adaptive and innate cells in the immune system

Answer 1

Acquired/adapted: T and B cells only

Innate: phagocytes, NK, eosinophil, basophil, monocyte

Question 2

What are the primary lymphoid organs?

Where are immune cells developed?

Answer 2

Bone marrow and thymus.

immune cells develop from bone marrow stem cells.

Question 3

Main function of B and T cells

Answer 3

To respond to antigens

Question 4

Complete this:

1. Antigen from peripheral tissues –> …
2. antigen from blood infections –> …
3. antigen from mucosal surfaces –> …

Answer 4

1. –> darins to lymph nodes
2. –> collets in the spleen
3. –> accumulates in MALT (mucosal-associated lymphoid tissues)

Question 5

What is the Lymphatic System

Answer 5

system of vessels that drain lymphatic fluid (leukocytes, proteins, cell debris, pathogens, cancer) from tissues and takes it back to the circulatory system through muscle contractions. It is not a circuit.

Question 6

what is an antibody

Answer 6

soluble proteins with a high affinity that can bind to foreign antigens and fight off infections, viruses, cancer cells.

Question 7

describe the structure of an antibody

Answer 7

2 constants,binds receptors on cells

2 variables, different amino acids to bind to specific antigens

Question 8

what is the first type on antibody made in an immune response

Answer 8

IgM. can be pentameric. Specific IgM

detected in plasma indicates a recent/ongoing infection.

Question 9

4 examples of way antibodies act:

Answer 9

1. neutralisation: e.g. coats virus in antibodies to stop function its function to bind to other receptors.
2. opsonisation: promote phagocytosis via receptors for antibodies on phagocytes.
3. activation of the complement system
4. trigger mast cells to release histamine

Question 10

Once B & T cells recognise an antigen they…

Answer 10

1. proliferate (proliferation): clonal selection/expansion –> clone, same specificity & binding
2. differentiation: B and T cells develop mature “effector” cell function.
   • B cells become antibody-secreting plasma cells
   • T cells become CTL or T helper cells
   • Some T and B cells become long-lived memory cells

Question 11

Where do T cells mature

Answer 11

thymus

Question 12

What does acquired immunity response involve?

Answer 12

B cell antibody production, T helper cells, cytotoxic T lymphocytes (CTL)

Question 13

What parts of B cells and T cells recognise in order to bind to other molecules?

Answer 13

B cells recognise part of an intact antigen.

T cells recognize a peptide antigen on MHC