Lecture 14

Question 1

What is the property of HLA/b/c class 1?

Answer 1

• Found on virtually 
all nucleated cells.
• Co-dominant.
• Polymorphic.
• Present peptides 
to CD8 T cells.

Question 2

What is the property of HLA-DP/ DQ/ DR?

Answer 2

• Found on B cells and 
specialised APCs.
• Co-dominant.
• Polymorphic.
• Present peptides 
to CD4 T cells.

Question 3

describe cytokines?

Answer 3

• Low molecular weight glycoproteins
• Secreted by CD4 T cells and other cells
• Regulate immune and inflammatory response:
- quality
- amplitude
- duration
• Often called interleukins (between leukocytes)
• Produced transiently and locally
(paracrine or autocrine rather than endocrine)
• Multiple, overlapping actions depend on:
• concentration
• presence of other cytokines
• type of receptive cell
• history of receptive cell
• Immune ‘hormones’ but also affect and
produced by other systems

Question 4

what are the innate responses of cytokines?

Answer 4

• Pro-inflammatory (e.g. interleukin-1).
• Important early in infections.
• Limit tissue damage.
• Initiate adaptive immune mechanisms.
• Affect body temperature.
• Alter sleep patterns.

Question 5

what are the Adaptive Response Cytokines?

Answer 5

• Control B cell activation 
(e.g. interleukin-4).
• Control cytotoxic T cell 
activation 
(e.g. interferon-γ)

Question 6

what do Chemotactic Cytokines do?

Answer 6

• Chemokines.
• Promote neutrophil 
chemotaxis at sites 
of inflammation 
(e.g. interleukin-8)

Question 7

what do Haematopoietic Cytokines do?

Answer 7

• Affect blood cell development 
to produce cell types needed 
in certain situations
• Neutrophils during infection 
(e.g. G-CSF = Granulocyte 
Colony-Stimulating Factor)

Question 8

describe two types of adhesin molecules?

Answer 8

Selectins
• Weak interactions
• Direct cell traffic around body
• A bit like velcro
Integrins
• Strong cell-cell adhesion
• Hold cells in tissues together
• Hold lymphocytes together for activation

Question 9

what are Co-stimulator Molecules?

Answer 9

• Pairs of surface molecules expressed 
in cell-cell interactions.
• B7 on APC
• CD28 on T cells
• Expressed transiently.
• Modulate immune activation processes