Evidence for Extrathymic Changes

Extrathymic Development of Vcd 4 - positive T Cells

Summal~ It is known that rearrangement of the T cell antigen receptor (TCIL) gene occurs in the thymus during T cell development and consequently results both in the deletion of DNA between the variable (V) and diversity/joining segments and in the formation of a circular DNA with recombination signal sequences. Here, we provide evidence that Vot14 + TCR gene rearrangements take place in extrat...

Extrathymic development of V alpha 14-positive T cells

It is known that rearrangement of the T cell antigen receptor (TCR) gene occurs in the thymus during T cell development and consequently results both in the deletion of DNA between the variable (V) and diversity/joining segments and in the formation of a circular DNA with recombination signal sequences. Here, we provide evidence that V alpha 14+ TCR gene rearrangements take place in extrathymic...

Evidence for a step - wise program of T cell development within the human tonsil

Human T cell development within the thymus is a well-characterized event, and it is known that a functional thymus is required for normal T cell generation to take place. Individuals with poor thymic function, from either congenital abnormality or post-natal injury, have a difficult time mounting a proper immune response and suffer from debilitating immune deficiency. Thus, it would be highly b...

Evidence for the Extrathymic Origin of Intestinal TCR T Cells in Normal Rats and for an Impairment of This Differentiation Pathway in BB Rats

Molecular Evidence for a Thymus-Independent Partial T Cell Development in a FOXN1−/− Athymic Human Fetus

The thymus is the primary organ able to support T cell ontogeny, abrogated in FOXN1(-/-) human athymia. Although evidence indicates that in animal models T lymphocytes may differentiate at extrathymic sites, whether this process is really thymus-independent has still to be clarified. In an athymic FOXN1(-/-) fetus, in which we previously described a total blockage of CD4(+) and partial blockage...