Immune - Stem cell transplantation Flashcards
How does allogenic stem cell transplant work
Give high dose(lethal) of radio/chemo to patient - this kills proliferating cells in bone marrow
- Give SCT from donor (containing lymphoid SCs)
- The donor SCs develop into mature haemotopoeitic cells, thus replacing the patient’s immune system
How do we match a donor to the patient?
HLA type and blood group
HLA - what chromosome is it on? What do we match for?
Chr 6
We match for HLA- A/B/C/DR
How do we identify a patient’s HLA type now?
Look at their DNA with PCR
Does ethnicity have an effect on HLA type?
Some HLA types are common in all ethnicities
However, other HLA types are only seen in certain ethnicities
3 sources of stem cells for transplantation?
Bone marrow
Peripheral blood (after giving G-CSF)
Cord blood
How do we measure outcome of stem cell transplantation?
Relapse of original disease?
Overall survival
Disease free survival
Transplant related mortality
4 complications of SCT?
Graft failure (i.e. rejection)
GvHD
Infections
Relapse of initial disease
What factors affect SCT outcome?
Age of pt Gender of pt Disease phase Time to BMT donor - sibling or unrelated
In temporal order, what infections tend to affect SCT patients
Viral (HSV) –> fungal –> pneumococcal –> VZV reactivation
Which infection is associated with 92% mortality in SCT patients?
Aspergillosis
Risk factors for CMV reactivation in SCT patients?
- Patient and donor’s serological status (if they have been previously exposed to CMV, they’ll have antibodies against it!)
- Type of SC donor
- Type of transplant
- CMV viral load
Define graft versus host disease?
When the donor cells recognise the patient’s cells as foreign
Organs affected in acute GvHD?
Skin, GIT, liver
2 pathways of pathophysiology of GvHD?
Donor cells attack the host
Chemo/radio –> cytokine storm. Donor cells enter this cytokine storm and are aberrantly activated
