CD4 T cells, important components of the immune system, are found in specific locations throughout the body. Based on the provided information, these cells are present in significant numbers in certain immune organs, in very low numbers in the blood, and play a key role in the thymus, particularly noted in some species.
According to the reference, significant numbers of CD4 T cells exist among the lymphocytes in the immune organs kidney and spleen. This suggests that these organs serve as important reservoirs or sites of activity for CD4 cells.
In contrast to the immune organs, the concentration of CD4 cells in the blood is described as very low. This indicates that while they circulate, their primary locations for accumulation or function may be in specific tissues or organs rather than the general bloodstream.
The reference also highlights the thymus as a significant location, especially in the context of T cell maturation. In certain species, like the ginbuna crucian carp and rainbow trout, thymus lymphocytes are mainly comprised of CD4 cells, which is consistent with the known role of the thymus as the primary site for T cell development and maturation.
To summarize the locations mentioned:
- Kidney (Immune organ): Found in significant numbers among lymphocytes.
- Spleen (Immune organ): Found in significant numbers among lymphocytes.
- Blood: Present in very low numbers.
- Thymus: Lymphocytes mainly CD4 cells in ginbuna crucian carp and rainbow trout, consistent with its role as the site of T cell maturation.
These specific distributions underscore the specialized roles that different immune organs play in the lifecycle and function of CD4 T cells.
