Revisiting thymus function.

Jacques F A P Miller

doi:10.3389/fimmu.2014.00411

Abstract

OPINION article Front. Immunol., 28 August 2014Sec. T Cell Biology Volume 5 - 2014 | https://doi.org/10.3389/fimmu.2014.00411

Highlights

The thymus has been an organ in search of a function
Unlike lymphocytes obtained by thoracic duct cannulation or from spleen and lymph nodes, thymus lymphocytes were generally poor in their ability to initiate immune reactions after adoptive transfer to appropriate recipients
Defects in immune responsiveness had never been documented in mice whose thymuses had been removed during adult life, a fact that had led some groups to conclude that “the thymus gland does not participate in the control of the immune response” (3)

Summary

Introduction

The thymus has been an organ in search of a function. The fact that it is a large mass of tissue in infancy was not appreciated at the beginning of the twentieth Century, as autopsies performed in infants succumbing to fatal illnesses such as diphtheria, revealed a small thymus. Grafting a neonatal thymus 6 months after thymectomy restored the potential for leukemia development (8), and the virus could be recovered from the non-leukemic tissues of thymectomized mice (9). At that time Gowans had shown that small lymphocytes were not short lived cells, as had been thought before, but immunologically competent cells with a long lifespan, recirculating from blood through lymphoid tissues into lymph and able to initiate immunological reactions when appropriately stimulated by antigen (13).

Results

Conclusion