To study transplantation,its types,pathway and types of rejections

1. NAME: Fahima Ashraf Kasi
CMS:35862
Semester: 5th

2.  The act of transferring cells, tissues, or
organs from one site to a different site,
 OR

3.  Solid organ
 Kidney
 Heart
 Liver
 Hematopoietic stem cells
 RBC

4.  Most common transplant
The reason for this success is due to
the fact that RBCs don’t express MHC
antigen and express only Rh blood
group antigens
So it is easy to match the RBCs of the
donor and recipient
why RBCs lack MHC molecules ?

5. 1. Auto graft
2. Syngraft
3. Allograft
4. Xenograft

6.  An autograft is a transplant or graft from one
area of the body to another area on the same
individual.

7.  An isograft is a transplant or graft of cell ,
tissue or organs from on individual to
another one that are genetically identical to
one another that is “syngeneic”. The only
example is identical twins.

8.  . It is the graft from one individual to another
individual of the same species that differ
genetically or may be hopefully genetically
identical (siblings).

9.  It is a graft between the donor and recipient
of different species.
 Example transferring an organ from miece to
the rabbit

11.  Histocompatible= antigentically alike
No immune response
 Histoincompatible= not antigentically alike
Immune response develope

24.  The goal of every transplant is to avoid
immune response
 The immune responses occurs only in case of
allogeneic and xenogeneic as others are
genetically identical to you
 So there are two different ways that are body
treat to transplant

25.  Direct pathway
 Indirect pathway

26.  Recognition of an intact MHC molecules
displayed by donor APC in the graft
 Basically self MHC molecules recognize the
structure of an intact allogeneic MHC
molecules
 Involves both CD4 and CD8 T cells

27.  Donor MHC peptide is processed and
presented by recipient APC
 Basically donor MHC molecule is handled like
any foreign antigen
 Involves only CD4 cells
 Antigen presentation by class 2 MHC
molecules

29.  Hyper acute rejection
 Acute rejection
 Chronic rejection

30.  Occurs within a few minutes to hours of transplantation
 Result of destruction of the transplant by preformed
antibody
 Some produced by recipient before transplant
 Generated because of previous transplant, blood
transfusion or pregnancies
 Antibodies activate the complement system and then
platelets and deposition causing hemorrhaging and
swelling
 Cell mediated immune response is not involve at all in
this reaction

32.  Seen in recipient who has not previously
sensitized to the transplant.
 It is of two types
1. Humoral acute rejection
2. Cellular acute rejection

33.  Also known as antibody mediated rejection
 Occurs within the first three months following
transplantation.
 In the case of kidney transplant this manifest
as a sudden decline in kidney function.
 Donor specific antibody is detected and c4d
is deposited on the endothelium of the
kidney due to activation of complement
 C4 is an element of complement cascade
 Its degradation product (c4d) adheres to
endothelial cells

34.  Symptoms
 Enlargement and tenderness of the grafted
kidney
 Rise in serum level
 Fall in urine out put
 Decrease renal blood flow

35.  Usually occurs 1-6 weeks to several years
following transcription when doses of
immunosuppressive drugs are lowered.
 Intense infiltration of lymphocyte &
macrophages , is taking place at the rejection
site.

37.  This type of rejection occurs months or year
after the transplanted tissue has adopted its
normal function
 Major chronic rejection complications include
micro vascular inflammation transplant
dysfunction and failure.
 The rejection rate vary depending on the site
of transplanted tissue.

38.  A major issue of transplantation is whether
the transplanted organ or tissue will be
accepted by the recipient or not
 In order to achieve this goal
immunosuppressive drugs have been used to
reduce the overall immunocompenence of the
recipient to foreign antigen.
 The immunosuppressive drugs are used for 3
purposes

39.  Induction therapy
 Maintenance therapy
 Specific therapy

40.  This therapy is use to suppress the immune
system.
 This therapy may be used before the
transplant.
 For deceased organ the therapy began at the
time of transplant and continues for 2 weeks
to reduce the incidence of rejection

41.  To assure that immune system is at bay to
facilitate survival of the graft combination
therapy is used to meddle with specific
immune system. Typically the dose of
immunosuppressive drug used in this therapy
is reduced than induction therapy to allow the
immune system function and to lower the
occurrence of opportunistic infection

42.  In some cases acute rejection may occur
months or year after transplantation
 Treatment with immunosupressive drugs are
used in these situation and doses levels are
similar to those used in induction therapy