Neonatal Female Mice Research Articles

Histological observations on thymus grafts placed under the renal capsule in mice, with special reference to the occurrence of lymphoid nodules.

Histological studies were made of thymus grafts in dd-mice. Whole thymuses were removed from neonatal female mice, and grafted to the mother animals in the subcapsular space of the kidney. Thymus grafts rapidly regenerated, grew and then involuted in almost the same way as the normal thymus. Immediately after grafting, thymus grafts showed an extensively necrotic central area surrounded by a narrow peripheral zone of surviving cortical tissue. By 8 days after grafting, grafts regenerated from the peripheral zone and restored a structure essentially identical to the normal thymus. Most histological features of thymus grafts were similar to those of the normal thymus of corresponding age, although the cortex and medulla were irregularly distributed in grafts. In addition, many thymus grafts contained lymphoid nodules with germinal centers within the medulla. The mechanism by which lymphoid nodules appeared in thymus grafts is unknown, but is discussed in some detail in light of the recent information available.