Immunology of organ and tissue transplantation

Introduction 

Organ transplantation is the process of moving organs from one site to another, which can be within the body of the same person or between a donor and recipient. The complex mechanisms of the immunity system pose serious complications as it can reject the transplanted organs or tissues; hence, the immunology of organ transplantation is very important in organ or tissue transplant. By the end of the article, an analysis of the role of secondary lymphoid organs in immunology can be evaluated. 

What is the Immunology of organ transplantation?

In case of an organs such as kidney, it is transplanted to another individual belonging to the same species. The immunity system is suppressed using medication, which inhibits the immune system from attacking the foreign organ or the tissue. The immunology of organ transplantation refers to the series of events that occurs after an allograft or xenograft. In fact, one of the major setbacks to the success achieved from organ transplant is the immune response of the recipient to the donor organ or tissue. In order to prevent the sequence of events of the immunology of organ transplantation certain medications are provided to the patient. 

Types of organ and tissue transplantation

There are several types of transplantation of organs and tissues at present.

• Autograft

It is the transplantation of cells, tissues, organs between two different sites and it is done on the same individual. Generally, skin grafting falls under this category.

• Allograft

It is the most common type of organ and tissue transplantation in which organs or tissues are transplanted from the donor to the recipient of the same species. 

• Xenograft

It refers to the organ and tissue transplantation between two different species. This type of organ transplant has immense gravity for the future because it can solve the challenge of undersupply of viable organs. 

• Stem cell transplant

Stem cells have the capacity to develop into different types of cells in the body. Blood stem cells are donated to rejuvenate destroyed or damaged cells; it is most commonly used to treat certain types of cancer. 

Role of secondary lymphoid organs in immunology

In the immunology of organ transplantation, secondary lymphoid organs are key determinants of a successful transplantation. Commonly secondary lymphoid tissues are spontaneously adaptive in immune response, even in case of microbial and tumour antigens immune responses are initiated with secondary lymphoid tissues. On the other hand, there is disagreement about the role of secondary lymphoid organs in immunology of organ transplantation.  There are several distinguishing aspects, which differentiates the immune response to the transplanted organ from other foreign antigens. The T-cells of the recipient recognize the donor and major histocompatibility complex, which exists in high frequencies. Humans possess high frequencies of alloreactive memory, which memorises prior infections or similar sensitive events. A transplant represents a unique foreign antigen, which evidently highlights the need to understand the immune system effectively in order to target allograft rejection. As a result, the secondary lymphoid organs and tissues through primary and memory alloimmune response leads up to graft rejection. 

Current state of Immunology of organ and tissue   transplantation 

India being a vast country has an enormous pool of critical patients who are in need of organ transplant. In 1994, Transplantation of Human Organs Act was introduced to provide a system of storage, removal and transplantation of human organs in India. Regional Organ and Tissue Transplant Organisation is also active in India to source organs for transplantation.  In case of acquiring donors, there are major setbacks in terms of sourcing the organs from the living relatives of the patient. After eliminating unwilling family members, only 35% of the relatives are found medically and physically fit to donate organs to the patient. On the other hand, the numbers of surgeons present in India who are capable of performing such critical operations are sufficient, which is praiseworthy. One of the most concerning matters about organ transplant in India is the poor infrastructure of government hospitals, which poses a major hindrance to immunology of organ transplantation. 

Conclusion 

It can be deduced that organ transplant is a major feat to fight against complexities posed by organ failure. Immunology of organ transplantation is the rejection of the organ or the tissues by the immune system of the recipient. It is usually taught by medication, which subdues the immunity system of the recipient.