IIH L22-L27 Clinical Immunology Block Flashcards
What are polyclonal antibodies? L22
ABs secreted by different B cell lineages
What are monoclonal antibodies? L22
ABs secreted by a single cell lineage
Example of monoclonal antibody? L22
Muromomab (anti-CD3)
Advantages of clonal antibodies over natural antibodies? L22
High specificity
Relatively long half-life
What are Antibody Drug Conjugates (ADCs)? L22
Highly potent chemotherapy agents are attached to an antibody and given to a pt. This increases the dose of drug that can be given while reducing toxicity.
What is Adoptive Cell Therapy (ACT)? L22
T cells are taken from a pt’s blood or tumour, and expanded in the lab to large numbers using cytokines. The T cells are then infused back into the pts and the tumour may be destroyed.
Three types of transplants? L23
Autologous- from the same pt
Allogeneic- from a different person
Xenogeneic- from an animal
3 class-I HLA antigens? L23
HLA-A
HLA-B
HLA-C
3 class-II HLA antigens? L23
HLA-DR
HLA-DP
HLA-DQ
How many sets of HLA antigen do we have? L23
Two; one from mother and one from father
What is the chance two siblings will be ‘HLA-identical’? L23
25%
HLA antigens are important in transplantation because…
L23
They mediate T cell rejection of the organ
They are major targets for AB mediated rejection of a graft
Define minor histocompatibility molecules. L23
Any other polymorphic molecule which can be recognised by T cells
E.g. H-Y antigens can mediate rejection of organs derived form men transplanted into women
What is Graft vs Host Disease (GvHD)? L23
The transferred T cell immunity attacks the host
Do SCT pts have to take immunosuppressants permanently? L23
No as tolerance usually develops and they can permanently stop all immunosuppressants
HLA matching is more important for SOT or SCT? L23
SCT
What is screened for SOT? L23
Antibodies in pt against the HLA molecules on the donor
Blood group antigen of the donor
What is hyper-acute rejection? L23
Where antibodies bind to the graft and activate complement and destroy the graft within a few hours. Recipients are ABO blood group typed to prevent this happening.
What is alloimmunisation? L23
Patients develop antibodies against HLA proteins which are non-self
What is Acute allograft rejection? L23
Occurs within 7 days post transplant and is mediated by T cell rejection of the graft. Treated with high dose immunosuppressants.
What is Chronic allograft rejection? L23
The adaptive immune system gradually rejects the kidney tissue or the vascular tissue supplying the kidney. T cells and macrophages are seen at the sit of organ injury.
5 main types of HSCT? L23
Autograft HLA-identical sibling allograft Matched Unrelated Donor (MUD) allograft Haploidentical allograft Cord blood allograft
What is ‘conditioning’ and what is myeloablative?
Treating a pt with high dose chemotherapy before HSCT transplant. Myeloablative is when the conditioning completely destroys the haemopoeitic system.
What is ‘engrafting? L23
Allowing space for the donor HSC to grow, achieved by conditioning
