Research Paper|Volume 6, Issue 6|pp 440—453

Age-related increase of VGF-expression in T lymphocytes

Stefan Busse¹, Johann Steiner^1,^2,³, Justus Micheel¹, Henrik Dobrowolny¹, Christian Mawrin⁴, Tim J. Krause¹, Michael Adamaszek⁵, Bernhard Bogerts^1,², Ursula Bommhardt⁶, Roland Hartig⁶, Mandy Busse⁷

¹Department of Psychiatry, University of Magdeburg, Magdeburg, Germany
²Center for Behavioral Brain Sciences, Magdeburg, Germany
³Pembroke College, University of Cambridge, Cambridge, UK
⁴Department of Neuropathology, University of Magdeburg, Magdeburg, Germany
⁵Center of Neurological Rehabilitation, University of Leipzig, Leipzig, Germany
⁶Institute of Immunology, University of Magdeburg, Magdeburg, Germany
⁷Department of Pediatric Pulmonology, Allergology & Neonatology, Medical University of Hannover, Hannover, Germany

* * Equal contribution

Received: January 6, 2014Accepted: April 30, 2014Published: May 4, 2014

https://doi.org/10.18632/aging.100656

Copyright: © 2014 Busse et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

VGF is a protein expressed by neurons and processed into several peptides. It plays a role in energy homeostasis and promotes growth and survival. Recently, VGF mRNA was detected in peripheral leukocytes. Since it is known that aging is associated with a decrease in the development and function of neuronal as well as immune cells, we addressed the question whether a peripheral expression of VGF by CD3+ T cells and CD56+ NK cells is correlated with age. Therefore, the frequency of VGF+CD3+ and VGF+CD56+ cells was determined in mentally healthy volunteers aged between 22 and 88. We found an age-dependent increase in the number of VGF+CD3+ T cells that correlated with HbA1c and the body mass index (BMI). VGF-expression by NK cells was age-independent. Blockade of VGF reduced proliferation and secretion of cytokines such as IL-2, IL-17A, IL-1β, IL-10 and TNF by CD3+ T cells and PBMCs. Rapamycin-mediated T cell blockade significantly reduced the frequency of VGF-expressing T cells. We conclude that VGF contributes to survival and function of peripheral T cells. The age-dependent increase in VGF-expression could serve as mechanism that counterregulates the decrease in functionality of T lymphocytes.