Autoimmunity Flashcards
what is central tolerance?
deletion of self-reactive lymphocytes in primary lymphoid tissue
what is peripheral tolerance?
inactivation of self-reactive lymphocytes in peripheral tissues, that escaped central tolerance
what cell mediates peripheral tolerance?
regulatory T cells (TREG cells)
what is self tolerance?
when lymphocytes do not respond to specific self-antigens
what four types of T cells can a Th0 cell differentiate into?
TH1
TFH
TH2
TREG
what do TREG cells do?
inactivate lymphocytes
how do TREG cells suppress autoreactive T cells?
produce anti-inflammatory cytokines
what results in autoimmunity?
the failure of immunological tolerance
what is a monogenic autoimmune disorder?
one where a single gene defect causes the disease
name a monogenic autoimmune disorder
IPEX syndrome
what causes most autoimmune disorders?
defects in many different types of genes
when does IPEX syndrome present?
early childhood
name three symptoms of IPEX syndrome
severe infections
eczema
diarrhoea
what other disease do IPEX patients get at a young age?
diabetes mellitus
what is the cure for IPEX syndrome?
haematopoietic stem cell transplantation (HSCT)