Difference Between Allogeneic and Autologous Transplant

The key difference between allogeneic and autologous transplant depends on the source of the stem cells for transplantation. Allogeneic transplant uses new stem cells from a different donor while autologous transplant uses patient’s own stem cells.

Stem cells are undifferentiated cells that can divide and differentiate into different other types of cells. Consequently, these cells have the ability to self-renewal. Therefore, they are the foundation for our organs and tissues. Furthermore, they act as a repair system of our body. Since the stem cells are capable of producing more daughter cells of the same type or differentiating into specific cell types, they are used in stem cell therapies to replace malfunctioning or diseased tissues with healthy tissues. Stem cell therapy can be either allogeneic or autologous. It depends on the new stem cells used to replace the tissue in transplantation. In the stem cell therapy, if the stem cells used is patient’s own, it is known as an autologous transplant. But, if it is from a different donor, then it is called allogeneic transplant.

CONTENTS

1. Overview and Key Difference
2. What is Allogeneic Transplant
3. What is Autologous Transplant
4. Similarities Between Allogeneic and Autologous Transplant
5. Side by Side Comparison – Allogeneic vs Autologous Transplant in Tabular Form
6. Summary

What is Allogeneic Transplant?

Allogeneic transplant refers to a stem cell transplantation that uses new stem cells from a different donor. Allogeneic transplant restricts into younger patients than elderly patients. During the allogeneic transplant, it is utmost important to match the stem cells of the donor with the patient’s stem cells. Otherwise, the patient’s immune system will reject these cells. Hence, more commonly, siblings become perfect matches for this purpose. However, unrelated donors also can be perfect matches when tested. After the transplant, it is necessary to give immunosuppressive medications to the patient in order to minimize immune rejection.

The graft that uses in allogeneic transplant is more often contamination free with diseased or cancer cells. But, in comparison to autologous transplant, the allogeneic transplant has a higher risk for opportunistic infections, graft failure, treatment-related mortality, life threatening complications, etc. In general, an allogeneic transplant is commonly used in the treatments of leukaemias and myelodysplastic syndromes. Though allogeneic transplantation is not readily available, it is very important since it has a lower risk of disease recurrence.

What is Autologous Transplant?

Autologous transplant is a type of stem cell transplantation that uses patient’s own stem cells to replace diseased cells. It is readily available. Furthermore, it provides a lot of advantages. Opportunistic infections are less in autologous transplant. Moreover, there is a lower risk of graft failure, treatment-related mortality, life threatening complications, etc. Furthermore, it is no need to match the stem cells with patient’s stem cells.

Moreover, autologous transplant does not need immunosuppressive therapy after the transplantation. Most importantly, in autologous transplant, immune reconstitution is high compared to allogeneic transplant. Furthermore, graft rejection occurs very rarely in this transplant. Often, autologous transplant carries out for the elderly patients. In general, autologous transplants have been used more often in solid tumours, lymphoma, and myeloma.

What are the Similarities Between Allogeneic and Autologous Transplant?

• Allogeneic and autologous transplant are two types of stem cell transplantation methods.
• In both cases, new stem cells are used to replace diseased tissues.
• The selection of allogeneic and autologous transplant depends on the type of malignancy, the age of the recipient, availability of a suitable donor, the ability to collect a tumour-free autograft, the stage and status of the disease, etc.
• Both types of transplants may cause life threatening complications, graft failure, opportunistic infections, treatment-related mortality, etc.

What is the Difference Between Allogeneic and Autologous Transplant?

In an allogeneic transplant, the stem cells used, are from a different donor. But, in an autologous transplant, the stem cells used are the patient’s own stem cells. Therefore, this is the key difference between allogeneic and autologous transplant. In an allogeneic transplant, it is necessary to match the donor stem cells with patient’s stem cells. But, there is no need for this procedure in autologous transplant since it uses patient’s own stem cells. Thus, it is another difference between allogeneic and autologous transplant.

Moreover, a noteworthy difference between allogeneic and autologous transplant is that the allogeneic transplant has a higher risk of opportunistic infections than the autologous transplant. Not only that, the allogeneic transplant has a higher risk of graft failure and graft rejection than the autologous transplant. Hence, this is a significant difference between allogeneic and autologous transplant. However, an allogeneic transplant is good in comparison to autologous transplant since its disease recurrence rate is low than in autologous transplant. Furthermore, an allogeneic transplant is more suitable for younger patients while the autologous transplant is more suitable for elderly patients. So, we can consider this also as a difference between allogeneic and autologous transplant.

The below infographic presents more information on the difference between allogeneic and autologous transplant.

Summary – Allogeneic vs Autologous Transplant

Stem cell transplant can be either allogeneic or autologous. It depends on several factors. Allogeneic transplant uses new stem cells from a different donor. On the other hand, autologous transplant uses the patient’s own stem cells. This is the key difference between allogeneic and autologous transplant. Furthermore, the allogeneic transplant has a higher risk of graft failure, graft rejection, life threatening complications, treatment-related mortality, etc., than an autologous transplant. Furthermore, after allogeneic transplant, it is necessary to give immunosuppressive medication for the patient while it is no need in autologous transplant. This summarizes the difference between allogeneic and autologous transplant.

Reference:

1. Champlin, Richard. “Selection of Autologous or Allogeneic Transplantation.” Current Neurology and Neuroscience Reports., U.S. National Library of Medicine, 1 Jan. 1970. Available here  
2. “Stem-Cell Therapy.” Wikipedia, Wikimedia Foundation, 13 Jan. 2019. Available here  

Image Courtesy:

1.”21240534639″ by Libertas Academica (CC BY 2.0) via Flickr
2.”Bone marrow biopsy”By Photographer’s Mate 2nd Class Chad McNeeley – Navy News Service, 021204-N-0696M-180, (Public Domain) via Commons Wikimedia