Transplantable organs and tissues may refer to both organs and tissues that are relatively often transplanted (here "major organs and tissues"), as well as organs and tissues which are relatively seldom transplanted (here "non-major organs and tissues"). In addition to this it may also refer to possible-transplants which are still in the experimental stage.

Major organs, tissues or cells

Heart

Heart transplantation is performed on patients with end-stage

heart failure Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome caused by an impairment in the heart's ability to Cardiac cycle, fill with and pump blood. Although symptoms vary based on which side of the heart is affected, HF ...

or severe

coronary artery disease Coronary artery disease (CAD), also called coronary heart disease (CHD), or ischemic heart disease (IHD), is a type of cardiovascular disease, heart disease involving Ischemia, the reduction of blood flow to the cardiac muscle due to a build-up ...

. The most common procedure is to take a working

heart The heart is a muscular Organ (biology), organ found in humans and other animals. This organ pumps blood through the blood vessels. The heart and blood vessels together make the circulatory system. The pumped blood carries oxygen and nutrie ...

from a recently deceased organ donor (

allograft Allotransplant (''allo-'' meaning "other" in Ancient Greek, Greek) is the Organ transplant, transplantation of cell (biology), cells, Biological tissue, tissues, or Organ (anatomy), organs to a recipient from a genetically non-identical donor of ...

) and implant it into the patient. The patient's own heart may either be removed ( orthotopic procedure) or, less commonly, left in to support the donor heart ( heterotopic procedure). It is also possible to take a heart from another species (

xenograft Xenotransplantation (''xenos-'' from the Greek meaning "foreign" or strange), or heterologous transplant, is the transplantation of living cells, tissues or organs from one species to another.artificial one, although the outcome of these two procedures has been less successful in comparison to the far more commonly performed

Lung

While lung transplants carry certain associated risks, they can also extend life expectancy and enhance the quality of life for end-stage pulmonary patients. While the precise details of surgery will depend on the exact type of transplant, there are many steps which are common to all of these procedures. Prior to operating on the recipient, the transplant surgeon inspects the donor lung(s) for signs of damage or disease. If the lung or lungs are approved, then the recipient is connected to an IV line and various monitoring equipment, including

pulse oximetry Pulse oximetry is a noninvasive method for monitoring blood oxygen saturation. Peripheral oxygen saturation (SpO2) readings are typically within 2% accuracy (within 4% accuracy in 95% of cases) of the more accurate (and invasive) reading of art ...

. The patient will be given general

anesthesia Anesthesia (American English) or anaesthesia (British English) is a state of controlled, temporary loss of sensation or awareness that is induced for medical or veterinary purposes. It may include some or all of analgesia (relief from or prev ...

, and a machine will breathe for them. It takes about one hour for the pre-operative preparation of the patient. A single lung transplant takes about four to eight hours, while a double lung transplant takes about six to twelve hours to complete. A history of prior chest surgery may complicate the procedure and require additional time.

Heart-lung

A heart-lung transplant is a procedure carried out to replace both

and

lungs The lungs are the primary organs of the respiratory system in many animals, including humans. In mammals and most other tetrapods, two lungs are located near the backbone on either side of the heart. Their function in the respiratory syste ...

in a single operation. Due to a shortage of suitable donors, it is a rare procedure; only about a hundred such transplants are performed each year in the United States. The patient is anesthetised. When the donor organs arrive, they are checked for fitness; if any organs show signs of damage, they are discarded and the operation cancelled. In order to avoid removal of recipient organs when donor organs are not viable, it is standard procedure that the patient is not operated on until the donor organs arrive and are judged suitable, despite the time delay this involves. Once suitable donor organs are present, the

surgeon In medicine, a surgeon is a medical doctor who performs surgery. Even though there are different traditions in different times and places, a modern surgeon is a licensed physician and received the same medical training as physicians before spec ...

makes an incision starting above and finishing below the sternum, cutting all the way to the bone. The skin edges are retracted to expose the sternum. Using a bone saw, the sternum is cut down the middle. Rib spreaders are inserted in the cut, and spread the ribs to give access to the heart and lungs of the patient. The patient is connected to a

heart-lung machine Cardiopulmonary bypass (CPB) or heart-lung machine, also called the pump or CPB pump, is a machine that temporarily takes over the function of the heart and lungs during open-heart surgery by maintaining the circulation of blood and oxygen throu ...

, which circulates and oxygenates blood. The surgeon removes the failing heart and lungs. Most surgeons endeavour to cut blood vessels as close as possible to the heart to leave room for trimming, especially if the donor heart is of a different size than the original organ. The donor heart and lungs are positioned and sewn into place. As the donor organs warm up to body temperature, the lungs begin to inflate. The heart may fibrillate at first - this occurs because the

cardiac muscle Cardiac muscle (also called heart muscle or myocardium) is one of three types of vertebrate muscle tissues, the others being skeletal muscle and smooth muscle. It is an involuntary, striated muscle that constitutes the main tissue of the wall o ...

fibres are not contracting synchronously. Internal paddles can be used to apply a small electric shock to the heart to restore proper rhythm. Once the donor organs are functioning normally, the heart-lung machine is withdrawn, and the chest is closed.

Kidney

Kidney transplantation is the organ transplant of a

kidney In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organ (anatomy), organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and rig ...

in a patient with

end-stage renal disease Chronic kidney disease (CKD) is a type of long-term kidney disease, defined by the sustained presence of abnormal kidney function and/or abnormal kidney structure. To meet criteria for CKD, the abnormalities must be present for at least three mo ...

. Kidney transplantation is typically classified as deceased-donor (formerly known as cadaveric) or living-donor transplantation depending on the source of the recipient organ. Living-donor renal transplants are further characterized as genetically related (living-related) or non-related (living-unrelated) transplants, depending on whether a biological relationship exists between the donor and recipient.

Liver

Liver transplantation is the replacement of a diseased

liver The liver is a major metabolic organ (anatomy), organ exclusively found in vertebrates, which performs many essential biological Function (biology), functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of var ...

with a healthy liver

. The most commonly used technique is orthotopic transplantation, in which the native liver is removed and the donor organ is placed in the same anatomic location as the original liver. Liver transplantation nowadays is a well accepted treatment option for end-stage liver disease and acute liver failure.

Pancreas

A pancreas transplant involves implanting a healthy

pancreas The pancreas (plural pancreases, or pancreata) is an Organ (anatomy), organ of the Digestion, digestive system and endocrine system of vertebrates. In humans, it is located in the abdominal cavity, abdomen behind the stomach and functions as a ...

(one that can produce insulin) into a person who has

diabetes Diabetes mellitus, commonly known as diabetes, is a group of common endocrine diseases characterized by sustained high blood sugar levels. Diabetes is due to either the pancreas not producing enough of the hormone insulin, or the cells of th ...

. Because the pancreas performs functions necessary in the digestion process, the recipient's native pancreas is left in place, and the donated pancreas attached in a different location. In the event of rejection of the new pancreas, the recipient could not survive without the native pancreas still in place. The healthy pancreas comes from a donor who has just died or it may be a partial pancreas from a living donor. Whole pancreas transplants from living donors are not possible, again because the pancreas is a necessary organ for digestion. At present, pancreas transplants are usually performed in persons with insulin-dependent diabetes who have severe complications.

Intestine

Currently, approximately half are pediatric recipients. View Data Reports > National Data > Transplant, Intestine, & Transplant by Recipient Age">US Dept of Health and Human Services, Health Resources and Services Administration, Organ Procurement and Transplantation Network" > View Data Reports > National Data > Transplant, Intestine, & Transplant by Recipient Age
Retrieved 1 October 2010 The most common indications in adults are

ischemia Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems ...

(22%),

Crohn's disease Crohn's disease is a type of inflammatory bowel disease (IBD) that may affect any segment of the gastrointestinal tract. Symptoms often include abdominal pain, diarrhea, fever, abdominal distension, and weight loss. Complications outside of the ...

(13%), trauma (12%), and desmoid tumor (10%); and in pediatrics,

gastroschisis Gastroschisis is a birth defect in which the baby's intestines extend outside of the abdomen through a hole next to the belly button. The size of the hole is variable, and other organs including the stomach and liver may also occur outside the b ...

(21%),

volvulus A volvulus is when a loop of intestine twists around itself and the mesentery that supports it, resulting in a bowel obstruction. Symptoms include abdominal pain, abdominal bloating, vomiting, constipation, and bloody stool. Onset of symp ...

(18%), and

necrotizing enterocolitis Necrotizing enterocolitis (NEC) is an intestinal disease that affects premature or very low birth weight infants. Symptoms may include poor feeding, bloating, decreased activity, blood in the stool, vomiting of bile, multi-organ failure, and p ...

(12%). Higher graft and patient survival rates are seen at the more experienced transplant programs. Within the last few years, 1-year graft and patient survival at more experienced centers have reached 60% to 70% and 65% to 80%, respectively.

Cornea

Corneal transplantation is a

surgical procedure Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery s ...

where a damaged or diseased

cornea The cornea is the transparency (optics), transparent front part of the eyeball which covers the Iris (anatomy), iris, pupil, and Anterior chamber of eyeball, anterior chamber. Along with the anterior chamber and Lens (anatomy), lens, the cornea ...

is replaced by donated corneal tissue which has been removed from a recently deceased individual having no known diseases which might affect the viability of the donated tissue. The cornea is the clear part of

eye An eye is a sensory organ that allows an organism to perceive visual information. It detects light and converts it into electro-chemical impulses in neurons (neurones). It is part of an organism's visual system. In higher organisms, the ey ...

in front of the iris and

pupil The pupil is a hole located in the center of the iris of the eye that allows light to strike the retina.Cassin, B. and Solomon, S. (1990) ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company. It appears black becau ...

. The surgical procedure is performed by

ophthalmologists Ophthalmology (, ) is the branch of medicine that deals with the diagnosis, treatment, and surgery of eye diseases and disorders. An ophthalmologist is a physician who undergoes subspecialty training in medical and surgical eye care. Following a ...

, medical doctors who specialize in eyes, and are often done on an outpatient basis (the patient goes home following surgery).

Skin

Skin grafting is often used to treat: * Extensive

wound A wound is any disruption of or damage to living tissue, such as skin, mucous membranes, or organs. Wounds can either be the sudden result of direct trauma (mechanical, thermal, chemical), or can develop slowly over time due to underlying diseas ...

ing or trauma *

Burns Burns may refer to: Astronomy * 2708 Burns, an asteroid * Burns (crater), on Mercury People * Burns (surname), list of people and characters named Burns ** Burns (musician), Scottish record producer Places in the United States * Burns, ...

* Areas of prior infection with extensive skin loss * Specific surgeries that may require skin grafts for healing to occur Skin grafts are often employed after serious injuries when some of the body's skin is damaged. Surgical removal (excision or debridement) of the damaged skin is followed by skin grafting. The grafting serves two purposes: it can reduce the course of treatment needed (and time in the hospital), and it can improve the function and appearance of the area of the body which receives the skin graft.

Blood

Blood transfusion is the process of transferring

blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood is com ...

or blood-based products from one person into the

circulatory system In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart ...

of another. Blood transfusions can be life-saving in some situations, such as massive blood loss due to trauma, or can be used to replace blood lost during

surgery Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery s ...

. Blood transfusions may also be used to treat a severe

anaemia Anemia (also spelt anaemia in British English) is a blood disorder in which the blood has a reduced ability to carry oxygen. This can be due to a lower than normal number of red blood cells, a reduction in the amount of hemoglobin availab ...

thrombocytopenia In hematology, thrombocytopenia is a condition characterized by abnormally low levels of platelets (also known as thrombocytes) in the blood. Low levels of platelets in turn may lead to prolonged or excessive bleeding. It is the most common coag ...

caused by a blood disease. People with

hemophilia Haemophilia (British English), or hemophilia (American English) (), is a mostly inherited genetic disorder that impairs the body's ability to make blood clots, a process needed to stop bleeding. This results in people bleeding for a long ...

sickle-cell disease Sickle cell disease (SCD), also simply called sickle cell, is a group of inherited haemoglobin-related blood disorders. The most common type is known as sickle cell anemia. Sickle cell anemia results in an abnormality in the oxygen-carrying ...

may require frequent blood transfusions. Early transfusions used

Whole Blood Whole blood (WB) is human blood from a standard blood donation. It is used in the treatment of massive bleeding, in exchange transfusion, and when people donate blood to themselves (autologous transfusion). One unit of whole blood (approxima ...

, but modern medical practice is to use only components of the blood.

Hematopoietic stem cells

Hematopoietic stem cell transplantation (HSCT) is the transplantation of blood stem cells derived from the

bone marrow Bone marrow is a semi-solid biological tissue, tissue found within the Spongy bone, spongy (also known as cancellous) portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production (or haematopoiesis). It i ...

(that is, bone marrow transplantation) or

. Stem cell transplantation is a medical procedure in the fields of

hematology Hematology (American and British English spelling differences#ae and oe, spelled haematology in British English) is the branch of medicine concerned with the study of the cause, prognosis, treatment, and prevention of diseases related to bloo ...

and

oncology Oncology is a branch of medicine that deals with the study, treatment, diagnosis, and prevention of cancer. A medical professional who practices oncology is an ''oncologist''. The name's Etymology, etymological origin is the Greek word ὄγ ...

, most often performed for people with diseases of the

, or certain types of

cancer Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...

. Stem cell transplantation was pioneered using bone-marrow-derived stem cells by a team at the

Fred Hutchinson Cancer Research Center The Fred Hutchinson Cancer Center, formerly known as the Fred Hutchinson Cancer Research Center and also known as Fred Hutch or The Hutch, is a cancer research institute established in 1975 in Seattle, Washington (state), Washington. History ...

from the 1950s through the 1970s led by

E. Donnall Thomas Edward Donnall "Don" Thomas (March 15, 1920 – October 20, 2012)Frederick R. Appelbaum.Perspective: E. Donnall Thomas (1920–2012) Science 338(6111):1163, 30 November 2012 was an American physician, professor emeritus at the University o ...

, whose work was later recognized with a

Nobel Prize The Nobel Prizes ( ; ; ) are awards administered by the Nobel Foundation and granted in accordance with the principle of "for the greatest benefit to humankind". The prizes were first awarded in 1901, marking the fifth anniversary of Alfred N ...

in Physiology and Medicine. Thomas' work showed that bone marrow cells infused intravenously could repopulate the bone marrow and produce new

blood cell A blood cell (also called a hematopoietic cell, hemocyte, or hematocyte) is a cell produced through hematopoiesis and found mainly in the blood. Major types of blood cells include red blood cells (erythrocytes), white blood cells (leukocytes), ...

s. His work also reduced the likelihood of developing a life-threatening complication called

graft-versus-host disease Graft-versus-host disease (GvHD) is a syndrome, characterized by inflammation in different organs. GvHD is commonly associated with bone marrow transplants and stem cell transplants. White blood cells of the donor's immune system which rema ...

. The first physician to perform a successful human bone marrow transplant was Robert A. Good. With the availability of the stem cell growth factors GM-CSF and

G-CSF Granulocyte colony-stimulating factor (G-CSF or GCSF), also known as colony-stimulating factor 3 (CSF 3), is a glycoprotein that stimulates the bone marrow to produce granulocytes and stem cells and release them into the bloodstream. Function ...

, most hematopoietic stem cell transplantation procedures are now performed using stem cells collected from the

peripheral blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the Cell (biology), cells, and transports Metabolic waste, metabolic waste products away from th ...

, rather than from the bone marrow. Collecting peripheral blood stem cells provides a bigger graft, does not require that the donor be subjected to

general anesthesia General anaesthesia (UK) or general anesthesia (US) is medically induced loss of consciousness that renders a patient unarousable even by painful stimuli. It is achieved through medications, which can be injected or inhaled, often with an analgesi ...

to collect the graft, results in a shorter time to engraftment, and may provide for a lower long-term relapse rate. Hematopoietic stem cell transplantation remains a risky procedure with many possible complications; it has traditionally been reserved for patients with life-threatening diseases. While occasionally used experimentally in nonmalignant and nonhematologic indications such as severe disabling auto-immune disease and

cardiovascular disease Cardiovascular disease (CVD) is any disease involving the heart or blood vessels. CVDs constitute a class of diseases that includes: coronary artery diseases (e.g. angina, heart attack), heart failure, hypertensive heart disease, rheumati ...

, the risk of fatal complications appears too high to gain wider acceptance.

Non-major organs, tissues or cells

Penis

The penis may be an

from a human donor, or it may be grown artificially, though the latter is untested in humans.

Uterus

A uterine transplant is the replacement of a

uterus The uterus (from Latin ''uterus'', : uteri or uteruses) or womb () is the hollow organ, organ in the reproductive system of most female mammals, including humans, that accommodates the embryonic development, embryonic and prenatal development, f ...

which has undergone

necrosis Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. The term "necrosis" came about in the mid-19th century and is commonly attributed to German pathologist Rudolf Virchow, who i ...

. Though the procedure has significant potential, it has been performed only a few times.

Thymus

Thymus The thymus (: thymuses or thymi) is a specialized primary lymphoid organ of the immune system. Within the thymus, T cells mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders. The thymus ...

transplantation can be used to treat infants with

DiGeorge syndrome DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a syndrome caused by a microdeletion on the long arm of chromosome 22. While the symptoms can vary, they often include congenital heart problems, specific facial features, frequent ...

, which results in an absent or hypoplastic thymus, in turn causing problems with the

immune system The immune system is a network of biological systems that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to bacteria, as well as Tumor immunology, cancer cells, Parasitic worm, parasitic ...

T-cell T cells (also known as T lymphocytes) are an important part of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell receptor (TCR) on their ce ...

mediated response. It is exclusively used in people with complete DiGeorge anomaly, which are entirely athymic. This subgroup represents less than 1% of DiGeorge syndrome patients.

Main Pulmonary Artery transplantation in Thymus Cancer

First main pulmonary artery transplant (homograft) was described to extend

treatment possibility for the first time in 2023 by Prof. Stefano Cafarotti (with Torre, Patella and Demertzis) in Switzerland, Ente Ospedaliero Cantonale.

Heart valve

Biological valves are valves of animals, like pigs, which undergo several chemical procedures in order to make them suitable for implantation in the human heart. The porcine (or pig) heart is most similar to the human heart, and therefore represents the best anatomical fit for replacement. Implantation of a porcine valve is a type of

Xenotransplantation Xenotransplantation (''xenos-'' from the Greek meaning "foreign" or strange), or heterologous transplant, is the transplantation of living cells, tissues or organs from one species to another.artery An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in ...

repair,

nerve A nerve is an enclosed, cable-like bundle of nerve fibers (called axons). Nerves have historically been considered the basic units of the peripheral nervous system. A nerve provides a common pathway for the Electrochemistry, electrochemical nerv ...

repair, then vein repair. The operation typically lasts 8 to 12 hours. By comparison, a typical

heart transplant A heart transplant, or a cardiac transplant, is a surgical transplant procedure performed on patients with end-stage heart failure when other medical or surgical treatments have failed. , the most common procedure is to take a functioning heart ...

operation lasts 6 to 8 hours. The recipient of a hand transplant needs to take

immunosuppressive drug Immunosuppressive drugs, also known as immunosuppressive agents, immunosuppressants and antirejection medications, are drugs that inhibit or prevent the activity of the immune system. Classification Immunosuppressive drugs can be classifie ...

s, as the body's natural

will try to reject, or destroy, the hand. These drugs cause the recipient to have a weak immune system and react severely even from minor infections. In 2008, surgeons in Munich transplanted two whole arms. The long-term results remain to be seen.

Leg

ischiopagi Ischiopagi comes from the Greek word ''ischio-'' meaning hip (ilium) and ''-pagus'' meaning fixed or united. It is the medical term used for conjoined twins (Class V) who are united at the pelvis. The twins are classically joined with the vertebr ...

conjoined twins Conjoined twins, popularly referred to as Siamese twins, are twins joined '' in utero''. It is a very rare phenomenon, estimated to occur in anywhere between one in 50,000 births to one in 200,000 births, with a somewhat higher incidence in south ...

, a healthy leg was transplanted from a dying conjoined twin to her sister. There is no need for immunosuppression because of the identical genetic make-up of the donor and recipient. The first leg transplant between genetically different people was performed in 2011, led by surgeon Pedro Cavadas. The procedure provided two legs to a double amputee, and recovery went well for about eight months. By then the man was able to stand up in a swimming pool. However, due to an unrelated illness, immunosuppressants had to be stopped, and the legs consequently needed to be amputated.

Ovary

Ovary transplantation, giving rise to successful pregnancies, will result in children who will have the genetic inheritance of the organ donor and not the recipient. It has so far only been carried out on

identical twins Twins are two offspring produced by the same pregnancy.MedicineNet > Definition of Twin Last Editorial Review: 19 June 2000 Twins can be either ''monozygotic'' ('identical'), meaning that they develop from one zygote, which splits and forms two e ...

, since the use of an ovarian transplant from a genetically identical donor prevents rejection of the donated organ. This bypasses the need for immune suppressants to maintain the function of the donated ovary, which is not vital for survival. More significantly, many immunosuppressants, such as

mycophenolate mofetil Mycophenolic acid is an immunosuppressant medication used to prevent rejection following organ transplantation and to treat autoimmune conditions such as Crohn's disease and lupus. Specifically it is used following kidney, heart, and live ...

, may cause birth defects. Ovary transplants in non-genetically identical individuals have been attempted, however they have ultimately failed. One example of this is

Lili Elbe Lili Ilse Elvenes (28 December 1882 – 13 September 1931), better known as Lili Elbe, was a Danish painter, transgender woman, and one of the earliest recipients of gender-affirming surgery (then called sex reassignment surgery). Elbe was a p ...

who received an ovary transplant in the early 1930s but died shortly thereafter due to various complications.Vaia Tsolas, Christine Anzieu-Premmereur, ''A Psychoanalytic Exploration of the Body in Today's World: On The Body'' (2017, )
page 234

Islets of Langerhans

Islet cell transplantation has the possibility of restoring beta cells and curing

. The Chicago Project headed at

University of Illinois The University of Illinois Urbana-Champaign (UIUC, U of I, Illinois, or University of Illinois) is a public university, public land-grant university, land-grant research university in the Champaign–Urbana metropolitan area, Illinois, United ...

at Chicago Medical Center is investigating ways to regenerate beta cells ''in vivo''. With that being said, beta cells experience

apoptosis Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...

early and thus are destroyed within a normal-functioning pancreas. The source of this seems to come from the transfer of Pander, a gene that works by attaching to

RNA Ribonucleic acid (RNA) is a polymeric molecule that is essential for most biological functions, either by performing the function itself (non-coding RNA) or by forming a template for the production of proteins (messenger RNA). RNA and deoxyrib ...

. Pander, when active, causes the beta cells to be blocked at

S phase S phase (Synthesis phase) is the phase of the cell cycle in which DNA is replicated, occurring between G1 phase and G2 phase. Since accurate duplication of the genome is critical to successful cell division, the processes that occur during S ...

, which induces apoptosis. This loss of beta cell mass eventually leads to a loss of most of the transplanted beta cells.

References

{{Organ transplantation Transplantation medicine