our p b p n blog.
this is : liveric.blogspot.com
A blog set up for the subject
Principles of Biochemistry & Physiology for Nutrition (PBPN)
by students of A7A1
just for Mdm Kalpana!:D
Our Question:
Our immune system tends to mount an immune response to the entry of an antigen from the same species (e.g. renal transplant).
- Discuss on the factors to be considered to prevent renal transplant rejection.
- Artificial implants (like pace makers, knee/hip joints?) and corneal transplants are not rejected by our immune system? Why?
Topic of Discussion:
* What is Immune System and How Does It Work?
* Renal Transplant Rejection
* Artificial implants and Corneal Transplants
* Q&A Session
* Interesting Facts!!
* Glossary
navigations are on top.=)
Monday, February 9, 2009
Topic:
Renal Transplantation Rejection
What is renal transplantation?
How does our body reject the newly transplanted kidneys?
And what are the factors to prevent the rejection of the transplanted kidneys?
Renal transplantation is a surgical procedure to replace malfunctioned kidneys that have already reached the end stage of organ failure (Brostoff, Male, Roitt & Roth, 1985).
Our immune system rejects the newly transplanted kidneys as it recognizes the organ to be “foreign” hence attacking the organ leading to rejection. The T cells or T lymphocytes in our body is responsible in rejecting the transplanted kidneys. The T lymphocytes distinguish a “self” from a “non-self” by the protein surface of the Major Histocompatibility Complex (MHC) or Human Leukocytes Antigens (HLA). The HLA cell surface protein of each individual recognizes the own body cells and prevent rejection reactions. The HLA identifies foreign molecules as well, presenting them to the T lymphocytes, which attacks the foreign molecules (University of Pennsylvania School of Medicine, 2008).
There are 3 types of rejection: hyperacute,acute and chronic rejection.
Factors we can prevent the rejection of transplanted kidneys are:
- to match the HLA of donor and recipient as to minimize the chances of rejection OR
- to use immunosuppressive drugs (Brostoff et. al,1985)
The HLA molecules are derived from our parents so it differs in each individual thus matching HLA molecules in transplant is difficult unless donor and recipient are related,example: sibling. There are three classes of HLA loci, HLA-A, HLA-B and HLA-C that need to be matched for the transplantation(Brostoff et. al,1985).
Immunosuppressive drugs are used to control rejection in transplanted kidneys and it work in 3 ways:
Firstly, it inhibits the activation of T lymphocytes. Drugs used are ciclosporin, sirolimus and tacrolimus
Secondly, it inhibits the cell division of T lymphocytes. Drugs used are 6-MP, Azathioprine and MPA.
Lastly, it acts as an anti-inflammatory agent. Drugs used is corticosteroids (Brostoff et. al,1985)
Long term intake of these drugs can lead to high chances of infection.
Reference:
- Brostoff, J., Male, D., Roitt, I., & Roth, D.B. (1985). Immunology: Transplantation and Rejection. Canada: Elsevier Ltd.
- University of Pennsylvania School of Medicine (2008, December 9). Understanding Donor-recipient Genetics Could Decrease Early Kidney Transplant Complications. ScienceDaily. Retrieved February 1, 2009, from http://www.sciencedaily.com /releases/2008/11/081125161540.htm
