Preferred Label : Th1/Th2 Differentiation Pathway;
NCIt synonyms : Th1 Th2 Differentiation Pathway;
NCIt related terms : Th1/Th2 Differentiation;
Alternative definition : BIOCARTA: Helper T cells are found in two distinct cell types, Th1 and Th2, distinguished
by the cytokines they produce and respond to and the immune responses they are involved
in. Th1 cells produce pro-inflammatory cytokines like IFN-g, TNF-b and IL-2, while
Th2 cells produce the cytokines IL-4, IL-5, IL-6 and IL-13. The cytokines produced
by Th1 cells stimulate the phagocytosis and destruction of microbial pathogens while
Th2 cytokines like IL-4 generally stimulate the production of antibodies directed
toward large extracellular parasites. IL-5 stimulates eosinophil responses, also part
of the immune response toward large extracellular parasites. Th1 and Th2 are produced
by differentiation from a non-antigen exposed precursor cell type, Thp. Exposure of
Thp cells to antigen by antigen-presenting cells may result in their differentiation
to Th0 cells, not yet committed to become either Th1 or Th2 cells, although the existence
of Th0 cells is controversial. Cells committed as either Th1 or Th2 cells are called
polarized, whether they are effector cells actively secreting cytokines or are memory
cells. The stimulation of Thp cells by exposure to antigen-presenting cells induces
the proliferation of undifferentiated cells, and their expression of IL-2 and IL-2
receptor. The differentiation of Th1 cells and Th2 cells depends on the cytokines
they are exposed to. IL-12 causes Th1 differentiation and blocks Th2 cell production,
while IL-4 causes Th2 differentiation and antagonizes Th1 development. IL-18 also
induces Th1 differentiation. Polarized Th1 and Th2 cells also express distinct sets
of chemokine receptors that further modify their homing and other cellular responses.
Improved understanding of Th1 and Th2 differentiation will improve our overall understanding
of the immune system, its response to infection, and aberrant responses that lead
to disease. (This definition may be outdated - see the DesignNote.);
NCIt note : The BIOCARTA Definition (ALT_DEFINITION) for this pathway concept was provided by
BioCarta. This property was not created by, nor is it maintained by the NCI Thesaurus
staff. Additionally, BioCarta is no longer updating its pathway data; thus, the BIOCARTA
Definition might be outdated or inaccurate. Please see the Terms and Conditions for
Use at http://www.biocarta.com/.;
Biocarta ID : h_th1th2Pathway;
Origin ID : C39252;
UMLS CUI : C1515339;
Semantic type(s)
- has_gene_product_element
- pathway_has_gene_element
