Page 7 of 11

SU13.1-4 | Transplantation — Glossary

Glossary — SU13.1-4 | Transplantation

Key terms in this module. Tap a term to see its definition.

Acute rejection

Rejection over days to weeks, predominantly T-cell (cellular), presenting as graft dysfunction; usually reversible with intensified immunosuppression.

Alloantigen

A donor protein (chiefly HLA) recognised as foreign by the recipient's immune system.

Allograft

A graft between two genetically different members of the same species — the commonest clinical situation and the one the immune system rejects.

Allorecognition

Recipient T-cell recognition of donor HLA as foreign, by the direct (intact donor HLA) and indirect (processed donor antigen) pathways.

Antiproliferatives

Mycophenolate mofetil and azathioprine; inhibit lymphocyte proliferation; cause bone-marrow suppression.

Authorisation Committee

The statutory body that must approve a living donation by a non-near-relative, confirming consent is voluntary and that no commercial dealing is involved.

Autograft

A graft transferred within the same individual; never rejected.

Autonomy

The ethical principle of respecting genuine, informed and voluntary consent — from the donor in life or through their wishes and the family's decision after death.

Beneficence

The ethical principle of acting for the good of others — here, the benefit donation brings to the recipient.

Brain-stem death

Irreversible loss of brain-stem function, legally recognised as death under THOTA and certified by a board of medical experts; permits heart-beating deceased donation.

Calcineurin inhibitors

Ciclosporin and tacrolimus; block calcineurin and IL-2-driven T-cell activation — the backbone of maintenance therapy; nephrotoxic.

Chronic rejection

Rejection over months to years with progressive fibrosis and graft vasculopathy; treatment-resistant and the main cause of late graft loss.

Commercial dealing in organs

The buying, selling or trading of human organs — a punishable offence under THOTA and the central safeguard against exploitation of the poor.

Crossmatch

Test mixing recipient serum with donor lymphocytes to detect preformed anti-donor antibodies; a positive result contraindicates transplantation.

Deceased donor

A person who donates organs after death; the source of most organs and of hearts, lungs and pancreases.

Decoupling

The principle that the notification of death and the request for organ donation must be handled as two separate conversations, never merged.

Donation after brain death (DBD)

Deceased donation following certified brain-stem death in a ventilated, heart-beating donor with well-perfused organs — the ideal scenario.

Donation after circulatory death (DCD)

Deceased donation following death confirmed by irreversible cessation of circulation and respiration, requiring rapid retrieval to limit warm ischaemia.

Graft-versus-host disease

Donor immune cells attacking the recipient's tissues — the reverse direction of attack (bone-marrow/intestinal transplantation).

HLA class I

HLA-A, B and C, expressed on all nucleated cells, presenting antigen to CD8 cytotoxic T cells.

HLA class II

HLA-DR, DQ and DP, expressed on antigen-presenting cells, presenting antigen to CD4 helper T cells.

Human leucocyte antigens (HLA)

The human major histocompatibility complex molecules, encoded on chromosome 6, that mark a graft as foreign; highly polymorphic.

Hyperacute rejection

Rejection within minutes to hours from preformed anti-ABO/anti-HLA antibodies (type II); causes vascular thrombosis and is untreatable — prevented by matching.

Induction immunosuppression

Intense immunosuppression given at transplantation (e.g. basiliximab, anti-thymocyte globulin) to cover the early high-risk period.

Isograft

A graft between genetically identical individuals (identical twins); immunologically accepted.

Justice

The ethical principle of fair, transparent, need-based allocation of organs — not allocation by wealth or influence.

Living donor

A competent adult who donates a paired or partial organ (e.g. a kidney or liver segment) while alive, with informed voluntary consent and minimised risk.

Maintenance immunosuppression

Lifelong combination therapy continued to prevent rejection, balancing efficacy against toxicity.

MTOR inhibitors

Sirolimus and everolimus; block mTOR proliferation signalling; impair wound healing and cause dyslipidaemia.

Near-relative

Under THOTA, a spouse, son, daughter, father, mother, brother, sister, grandparent or grandchild — a living donor in this category needs no Authorisation Committee approval.

Non-maleficence

The ethical principle of avoiding harm — especially relevant to minimising risk to the living donor.

Organ donation

The giving of an organ or tissue, by a living person or after death, for transplantation into another; it benefits the recipient, not the donor.

Transplant coordinator

A trained professional who supports families through the donation decision and manages the donation pathway, often best placed to raise the donation request.

Transplantation

Transfer of an organ or tissue to replace failed function; its central obstacle is immunological rejection of the graft.

Transplantation of Human Organs Act (THOTA) 1994

The Indian statute (amended 2011) governing organ donation and transplantation — recognising brain-stem death, prohibiting organ commerce, and regulating living and deceased donation.

Xenograft

A graft between different species, which faces the most severe rejection.

36 terms in this module