Age-related changes in p56lck protein levels and phenotypic distribution of T lymphocytes in young rats

Clin Dev Immunol. 2005 Mar;12(1):75-84. doi: 10.1080/17402520400017393.

Abstract

p56lck is involved in the maturation of T-cells from double negative (DN) into double positive (DP) T-cells. The objective of this experiment was to determine changes in the levels of thymic and splenic T-cell p56lck using Western immunoblotting, along with the proportion and number ofT-cell subsets in thymus, spleen and blood using flow cytometry in growing Sprague-Dawley rats. Thymic p56lck levels were negatively correlated with age (r = - 0.42, p = 0.04) and positively correlated with age in the spleen (r = 0.50, p = 0.01). Nine-week-old rats had a higher percentage of thymic DN and CD8 cells with fewer DP cells compared to younger rats. There were minor differences in the proportions of T-cell subsets in the spleen and blood. T-cell numbers remained proportional to body weight in the lymphoid organs; however, the lower absolute number of T-cells in the younger rats might indicate that they are less able to respond to antigens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / physiology*
  • Animals
  • Body Weight
  • Lymph Nodes / cytology
  • Lymph Nodes / metabolism
  • Lymphocyte Count
  • Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / metabolism*
  • Male
  • Organ Size
  • Phenotype
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Antigen, T-Cell, alpha-beta / metabolism
  • Spleen / metabolism
  • T-Lymphocytes / cytology
  • T-Lymphocytes / metabolism*

Substances

  • Receptors, Antigen, T-Cell, alpha-beta
  • Lymphocyte Specific Protein Tyrosine Kinase p56(lck)