TrkB mRNA and protein in mouse spleen: structure of the spleen of functionally deficient TrkB mice

Abstract

Whereas it is nowadays clear that neurotrophins are involved in the regulation of various aspects of the functioning of immune system, knowledge of their actual immunomodulatory roles is still fragmentary and incomplete. In this respect, knock-out mouse models remain particularly unexplored. In the present study, the expression of the TrkB neurotrophin receptor in murine spleen was addressed at the mRNA (reverse transcription/polymerase chain reaction) and protein (Western blot) levels. Once the presence of TrkB at both levels was demonstrated, the age-dependent changes in the pattern of expression of the receptor were analyzed and quantified, and TrkB-positive cells were identified by immunohistochemistry. TrkB-immunoreactive cells, identified as red pulp macrophages, were detected in the spleen throughout postnatal development and adult life; their numbers peaked at the age of 15 days. The absence of functional TrkB did not appear to result in morphological changes as assessed by light and electron microscopy of spleens from 15-day-old mice knockout for the trkB gene. The present results support the idea that, in the murine spleen, TrkB and its ligands are involved in macrophage physiology in a developmentally regulated fashion, but they do not seem to be essential for macrophage survival.

The Neurotrophic Receptor Ntrk2 Directs Lymphoid Tissue Neovascularization during Leishmania donovani Infection

“…Spleen tissue sections were analyzed for the expression of Ntrk2, the receptor for Bdnf to investigate a possible role for this pathway in vascular remodeling in vivo . In the naïve spleen, Ntrk2 expression was restricted to a population of F4/80 + red pulp MPs, corresponding to previous reports [ 31 ] ( Fig. 4B ).…”

Expression of NGF, BDNF and their high-affinity receptors in ovine mammary glands during development and lactation

“…Neurotrophins are mainly studied on nervous cells; however, as multifunctional growth factors, they can exert various effects through their receptors on non-neuronal cells such as kidney (Caroleo et al 2015), testis (Müller et al 2006), thymus (Maroder et al 2000), lymph node (García-Suárez et al 1997), skin (Di Marco et al 1993), spleen (Pérez-Pérez et al 2004), ovary (Seifer et al 2006), salivary glands and mammary ducts (Shibayama and Koizumi 1996;Sariola 2001).…”