Age-related differences in expression of signal differentiation factors for human thymic epithelial cells

Abstract

Expression of transcription proteins PAX1, Hoxa3, and TLP regulating differentiation of thymic epithelial cells is detected in human thymus starting from gestation week 22 until the age of 95 years. Expression of transcription factors significantly decreased during aging. Apart from the decrease in the expression of signal differentiation factors in cultured thymic epithelial cells, proliferative activity of T lymphocytes cocultured with thymic epithelial cells also decreased in aging cultures, which demonstrated the important regulatory effect of transcription proteins on maturation and maintenance of T lymphocytes. Taking into account the important role of transcription proteins in the regulation of proliferation and function of T lymphocytes, whose number sharply decreases during aging, the maintenance of the level of expression of transcription factors during aging is a promising trend in modern biogerontology.

Peptides Regulate Cortical Thymocytes Differentiation, Proliferation, and Apoptosis

“…The obtained results cohere with the experimental data which revealed a stimulating effect of the synthetic peptides of thymus and epiphysis on the differentiation of the polypotent cells [3, 6]. The retina peptides were shown earlier to stimulate proliferative activity of the pigmented epithelium [3].…”

“…The retina peptides were shown earlier to stimulate proliferative activity of the pigmented epithelium [3]. The experimental results obtained and the literature data available suggest that the peptide regulation is based on the ability of peptides to stimulate the proliferative activity and differentiation of cells.…”

“…An overt lowering of thymus functional activity in humans can be traced from the beginning of puberty and is associated with an early involution of this organ [3, 4]. Thymus involution is largely manifested by the reduced count of cortical thymocytes and mature T cells [1, 5].…”

Age-Associated Remodeling of Thymopoiesis: Role for Gonadal Hormones and Catecholamines

“…Therefore, if this age-associated decline in winged helix nude expression is not a result of fewer TECs present, it may be indicative of an altered TEC differentiation [125] . In addition, in human thymus, the expression of transcription proteins PAX1 and Hoxa3 regulating differentiation of TECs has been shown to decrease with advancing age [127] . Furthermore, an age-associated decrease in the expression of subunit 8 of keratin (K8) by TECs has been reported [125] .…”