File:Breast-and-other-cancer-dormancy-as-a-therapeutic-endpoint-speculative-recombinant-T-cell-receptor-1471-2407-10-251-S1.ogv

English: Video clip. The body is constantly attacked by infections and defended by a collection of antibodies. The infections are represented by 'lightings' that have colours: light or dark blue and silver. The antibody filter has the same colours. The circle is the body containing a tube, which is the lymphoid vessel. The tissue cells (coloured red, yellow, white, brown and purple) are in the central upper part. T cells are located in the lymph node at the edge of the lymphoid vessel. A large APC is located in the lower part. Tissue cell-derived peptides determine TCR specificity. Colours of T cells designate the self pMHCs, which rescued them during positive selection. Complementary self pMHCs and TCRs have identical colours. For the sake of simplicity, in the animation the many different self pMHCs in a single cell are neglected. One T cell recognizes only one self pMHC. The animation shows how the whole system is capable of determining whether a given pMHC is self or non-self. An individual T cell is unable to make such a decision. Together, however, they can because there is a complementary TCR for every self pMHC in the immune system that recognizes an individual peptide fragment. The self pMHCs are presented, one by one, as they flow via the lymph into the lymph node. Eventually, all soluble self pMHCs are captured by complementary TCRs. In this way all tissue cells remain intact. Finally, a viral infection, designated by green colour, enters the body and infects a cell changing its self peptide into a foreign peptide (fpMHC). The soluble f pMHC molecule (the danger signal in the Homeostatic Role of T cells model) freely crosses the lymphoid tissue because no complementary TCR is present. Eventually, fpMHC is captured by an APC, which initiates 2 independent processes. Firstly, the APC activates cytotoxic T cells to locate and eliminate the infection. The T cells travel via the blood vessel into the tissues. In the meantime the virus infects other cells in the body and is also released to the environment represented by small green dots. Secondly, the APC initiates hypermutation in B cells represented by coloured dots at the lower right part of the screen. Eventually, the green colour will appear as a new B cell clone and also become part of the extended immune defence filter.