During embryonic development, T lymphoid precursor cells colonize the thymus. Chemoattraction by the fetal thymus is thought to mediate T precursor cell colonization. However, the molecules that attract T precursor cells to the thymus remain unclear. By devising time-lapse visualization in culture, the present results show that alymphoid fetal thymus lobes attract T precursor cells from fetal l...

During embryonic development, T-lymphoid precursor cells colonize the thymus. Chemoattraction by the fetal thymus is thought to mediate T-precursor cell colonization. However, the molecules that attract T-precursor cells to the thymus remain unclear. By devising time-lapse visualization in culture, the present results show that alymphoid fetal thymus lobes attract T-precursor cells from fetal l...

A chemical fractionation procedure, previously found applicable to bovine thymus and bovine and ovine palatine tonsils, was used to fractionate rabbit and hog thymus. With respect to the chemical fractionation steps, yields of fractions, and optical and electrophoretic properties, extracts from hog and rabbit thymus were indistinguishable from similar extracts prepared from calf thymus. The stu...

Congenitally thymusless nude mice that lacked functional T cells were reconstituted with H-2-compatible or -incompatible thymus grafts taken from either fetal, newborn, or adult mice and transplanted under the kidney capsule or subcutaneously. Transplantation with unirradiated fetal (15--17 d) or newborn thymus grafts reconstituted the nude mice as assessed by their subsequent generation of vir...

Background & Objective: The thymus gland significantly affects fetal immune system maturation. Additionally, there is a linear association between size and its performance. Given the high prevalence of vitamin D deficiency in Iran scarce studies with conflicting results, subjecting maternal concentration effect on thymus, we decided to investigate relation mid-gestation. This study also aimed g...

Maintenance of the peripheral T-cell pool throughout the life requires uninterrupted generation of T cells. The majority of peripheral T cells are generated in the thymus. However, the thymus does not contain hematopoietic progenitors with unlimited self-renewing potential, and continuous production of T cells requires importation of such progenitors from the bone marrow into the thymus. Thymus...

The endodermal epithelial thymus anlage develops in tight association with neural crest (NC)-derived mesenchyme. This epithelial-NC interaction is crucial for thymus development, but it is not known how NC supports thymus development or whether NC cells or their progeny make any significant contribution to the adult thymus. By nude mouse blastocyst complementation and by cell surface phenotype,...

Thymic lymphocytes are continuously replaced by stem cells entering the thymus. The thymus of animals receiving lethal total body irradiation, followed by administration of bone marrow or spleen cells, is repopulated by cells derived from the inoculure (1-6). Similarly, repopulation of the unirradiated thymus eventually occurs in animals in which only the lower third of the body was irradiated ...

From the facts stated in this paper it is evident that the thymus gland of mammals contains a substance which is capable of producing tetany when fed to the larvae of certain species of salamanders (Ambystoma opacum and Ambystoma maculatum). As long as the larvae have not developed their own thymus glands, they are able, by means of some mechanism, to counterbalance the tetanic action of the th...