Transplant

What Is a Transplant?

A transplant is a surgical procedure in which an organ, tissue, or group of cells is moved from a donor to a recipient to replace something the body can no longer do on its own. The donated material, called a graft, does the work a failing or damaged part once did: filtering blood, pumping it, oxygenating it, restoring sight, rebuilding bone, or repairing a burned wound.

What makes transplantation different from most other surgery is that it depends entirely on a gift. No amount of medical skill can perform a heart transplant without a donated heart. That connection, between donation and transplantation, is the foundation of everything we do at Donor Alliance.

The two main types of transplants

Transplantation falls into two broad categories: organ transplantation and tissue transplantation. Both save and heal lives. Both begin with a person who chose to give.

Organ transplantation

Organ transplants replace a failing, life-sustaining organ with a healthy one from a donor. Right now, more than 100,000 people in the United States are waiting for an organ transplant [1], and more than 1,300 of them live right here in Colorado and Wyoming.

The organs that can be transplanted include the kidneys, liver, heart, lungs, pancreas, and small intestine. The kidney is by far the most needed, making up the vast majority of the national waiting list. Kidney failure affects millions of Americans, and while dialysis can sustain life, a transplant offers a longer life and a dramatically better quality of it.

A liver transplant treats end-stage liver disease, cirrhosis, certain cancers, and acute liver failure. The liver is the only solid organ that regenerates, which is why a portion of a healthy liver can be donated by a living person and regrow in both the donor and the recipient. A heart transplant is performed when heart failure has progressed to the point where no other treatment can help. A successful transplant doesn’t just extend life; it restores it. Heart transplant recipients go on to run half-marathons, raise their children, and return to careers they thought they’d left behind.

Lung transplants treat severe pulmonary diseases like COPD, cystic fibrosis, and pulmonary fibrosis, and can be performed as a single lung or double lung transplant.  A pancreas transplant treats type 1 diabetes and, in some cases, can eliminate the need for insulin entirely. It’s most often performed alongside a kidney transplant in patients who have experienced kidney failure as a result of their diabetes.  Small intestine transplants are the rarest of the common organ transplants, used when the intestine has failed and a patient is unable to absorb nutrition any other way. 

Tissue transplantation

Tissue transplants are far more common than organ transplants in terms of sheer volume, with roughly one and a half to two and a half million tissue grafts used in the United States each year.  One tissue donor can heal more than 75 people.

Corneal transplants restore sight to people whose corneas have been damaged by disease, injury, or birth defects. More than 97% of corneal transplants successfully restore vision, and a single cornea donor can give the gift of sight to two people.  Skin grafts are life-saving for severe burn victims, and also used in trauma care, surgical wound closure, and reconstructive procedures. Bone grafts prevent amputations, rebuild limbs, and are used in spinal and orthopedic surgeries; after blood, musculoskeletal tissue is the most commonly transplanted material in medicine.  Donated heart valves repair cardiac defects and damaged valves, and in younger patients can even grow with the recipient over time. Tendons and ligaments rebuild joints and restore mobility, while donated veins and blood vessels restore circulation in bypass surgery and help surgeons save limbs that would otherwise be lost.

Where transplanted organs and tissues come from

Transplants draw from two sources: deceased donors and living donors.

A deceased donor is someone who has died under specific medical circumstances that allow their organs or tissues to be recovered. There are two pathways. Donation after brain death (DBD) occurs when the brain has completely and irreversibly stopped functioning, though machines temporarily maintain circulation to preserve the organs. Donation after circulatory death (DCD) occurs when a patient who is dying but not brain dead chooses to withdraw life support, and donation follows the natural stopping of the heart.  Donor Alliance has invested in advanced preservation technologies that expand the number of organs we can use from DCD donors, allowing us to give more people a chance at a transplant.

A living donor is a healthy person who chooses to donate a kidney or a portion of their liver while still alive. Because the kidneys do their work in pairs and the liver regenerates, these donations can be made without serious long-term risk to the donor’s health, though every living donor undergoes a thorough medical and psychological evaluation to confirm they’re a good candidate.  Living donor kidney transplants actually tend to produce better outcomes than deceased donor transplants, partly because they can be scheduled in advance, which reduces the time the organ spends outside the body. 

Tissues can come from deceased donors of almost any age. There’s no strict cutoff. Medical suitability is evaluated at the time of donation.

How transplants work: from the waiting list to the operating room

Getting on the national transplant waiting list begins with a referral to a transplant center, a hospital equipped and staffed to perform transplants. The center conducts an extensive evaluation that covers the patient’s medical history, surgical candidacy, psychological readiness, and social support system. If the patient is accepted, the transplant center registers them in the national system managed by the United Network for Organ Sharing, known as UNOS. 

UNOS administers the Organ Procurement and Transplantation Network (OPTN), the national framework established by the National Organ Transplant Act of 1984 that governs how organs are matched and distributed.  When a deceased donor organ becomes available, the OPO serving that hospital, Donor Alliance in the case of Colorado and most of Wyoming, enters the donor’s information into the UNOS system. A new match list is generated for that specific organ, ranking candidates based on blood type compatibility, tissue type compatibility, medical urgency, body size, time on the list, and geographic proximity to the donor hospital. 

Race, gender, sexual orientation, religion, income, and social status are never part of the allocation process. 

The transplant team of the top-ranked candidate is contacted and given a short window to accept or decline the organ on their patient’s behalf. If they decline, the offer moves to the next person on the list. Once accepted, the logistics move quickly. Organs have narrow preservation windows: hearts and lungs are typically viable for four to six hours, livers for 12-24 hours, and kidneys for 24-36 hours with modern preservation technology. That urgency is why you’ll sometimes see news coverage of police escorts and chartered flights. Getting the organ to the recipient in time is never routine.

The science of matching: why compatibility matters

Transplantation works because the human immune system can learn to tolerate a new organ. But it doesn’t do so easily, and it doesn’t do so on its own. 

The immune system uses proteins called human leukocyte antigens (HLA) to distinguish the body’s own cells from foreign ones. Every person inherits a unique HLA profile from their biological parents. When a transplanted organ arrives with a different HLA profile, the immune system recognizes it as foreign and can attempt to attack it. This is called rejection.

Matching reduces that risk. Blood type compatibility is the baseline requirement. HLA typing identifies the specific antigen markers in both donor and recipient, and a closer match means a lower rejection risk. Crossmatching tests whether the recipient already has antibodies that would react immediately against the donor’s cells; a positive crossmatch typically means the transplant shouldn’t proceed with that donor. A test called the panel reactive antibody (PRA) test measures how sensitized a recipient is overall, which gives transplant centers a sense of how difficult it may be to find a compatible match.

Even with a good match, the immune system must be managed long-term. Solid organ recipients take immunosuppressive medications, sometimes called anti-rejection drugs, for the rest of their lives. These medications lower the immune response enough that the body tolerates the transplanted organ. The trade-off is a higher vulnerability to infection, which is why post-transplant care and monitoring are ongoing, lifelong commitments.

Transplant Outcomes

Modern transplantation works remarkably well, and outcomes have improved consistently over decades thanks to advances in matching, surgery, and immunosuppression. There’s many variables that factor into post-transplant outcomes; find up to date information on the Long-Term Outcome Explorer. 

Common questions and misconceptions about transplants

Does wealth or celebrity status get someone to the top of the waiting list? No. The matching system is blind to all of it. Rank is determined by medical need, compatibility, and time waiting. 

Can a doctor who knows I’m a registered donor deprioritize my care? No. The medical team treating you is entirely separate from the donation and transplant team. Donation is only considered after every life-saving effort has been made and death has been declared by the hospital’s medical team.

Is there an age limit for receiving a transplant? There’s no strict cutoff. Transplant centers evaluate candidacy individually, and patients well into their 70s and older successfully receive transplants each year.

Can a person who has already received a transplant donate their organs after death? Yes, in some cases. This is evaluated individually based on the function and condition of the organ, and in many instances, a previously transplanted organ can go on to save another life. 

Does tissue donation prevent an open-casket funeral? No. Recovery is performed by a surgical team with the same care given to any operating room procedure, and it doesn’t affect the ability to have an open-casket service. 

A brief history of transplantation

The first successful organ transplant was performed on December 23, 1954, when Dr. Joseph Murray and his team in Boston transplanted a kidney between identical twins, Richard and Ronald Herrick. Because the twins were genetically identical, Richard’s immune system accepted Ronald’s kidney without rejection. Murray was awarded the Nobel Prize in Physiology or Medicine in 1990.  In 1962, his team performed the first successful transplant from an unrelated, deceased donor using immunosuppressive drugs, opening the door to transplantation for the broader population. 

The first successful liver transplant was performed by Dr. Thomas Starzl in 1967 at what is now known as the University of Colorado Hospital. 

The introduction of cyclosporine in the 1980s changed everything. This immunosuppressive drug dramatically reduced rejection rates and transformed transplantation from a high-risk experimental procedure into a reliable, life-extending treatment.  Today, more than 875,000 Americans with organ failure have received transplants, and the field continues to advance. Researchers are now conducting clinical trials in xenotransplantation, using gene-edited animal organs in human patients, as one potential long-term answer to the organ shortage. 

Why donation is the foundation of transplantation

The shortage of donated organs and tissues is the central limiting factor in transplantation. Surgical skill, matching technology, and post-transplant care have all advanced enormously. The gap between need and supply remains.

Thirteen people die every day in the United States waiting for an organ transplant that didn’t arrive in time. There are more than 100,000 people on the national waiting list right now, and a new name is added every eight minutes. And yet, because of the circumstances required for organ donation, it’s incredibly rare that it is possible. 

Registration matters. Every person who registers as an organ, eye, and tissue donor expands the pool of potential donors, increases the chances that someone waiting will find a match, and gives their family the clarity of knowing their decision. In 2025, 314 deceased donors in our region led to 1,036 organ transplants. 

If you’re ready to make that decision, you can register today through Donate Life Colorado at DonateLifeColorado.org or through Donate Life Wyoming at DonateLifeWyoming.org. 

References

1. U.S. Department of Health and Human Services, Health Resources and Services Administration. “Organ Donation Statistics.” OrganDonor.gov. https://www.organdonor.gov/learn/organ-donation-statistics
2. U.S. Department of Health and Human Services, Health Resources and Services Administration. “Organs.” OrganDonor.gov. https://www.organdonor.gov/learn/organ-donation/organs
3. American Association of Tissue Banks. “About Tissue Banking.” AATB.org. https://www.aatb.org/about-tissue-banking
4. Eye Bank Association of America. “Eye Banking FAQs.” EBAA.org. https://www.ebaa.org/eye-banking-faqs/
5. Organ Procurement and Transplantation Network (OPTN). “Deceased Donation.” OPTN.transplant.hrsa.gov. https://optn.transplant.hrsa.gov/learn/about-donation/deceased-donation/
6. Scientific Registry of Transplant Recipients (SRTR). “SRTR Annual Data Report 2023.” SRTR.org. https://www.srtr.org/reports/srtransplant-annual-data-reports/
7. United Network for Organ Sharing (UNOS). “How We Match Organs.” UNOS.org. https://unos.org/transplant/how-we-match-organs/
8. International Society for Heart and Lung Transplantation (ISHLT). “ISHLT Fast Facts.” ISHLT.org. https://www.ishlt.org/registries-and-data/ishlt-international-registry-for-heart-and-lung-transplantation/ishlt-fast-facts
9. Nobel Prize Outreach. “Joseph E. Murray – Biographical.” NobelPrize.org. https://www.nobelprize.org/prizes/medicine/1990/murray/biographical/
10. Virginia Commonwealth University, Health Equity Program. “Medical Research and the First Heart Transplant in the South.” VCU.edu. https://healthequity.vcu.edu/history-and-health-program/learning-modules/medical-research-and-the-first-heart-transplant-in-the-south-/
11. U.S. Food and Drug Administration. “Xenotransplantation.” FDA.gov. https://www.fda.gov/vaccines-blood-biologics/xenotransplantation
12. Long-Term Outcome Explorer hrsa.gov Long-Term Outcomes Explorer | SRTR Patient Friendly Website