This article is part of a themed section on Recent Advances in Targeting Ion Channels to Treat Chronic Pain. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.12/issuetoc.

Mammary tumors are among the most common neoplastic conditions in dogs, and there is evidence that inflammation plays a role in the development of some tumor types in dogs. The complement system is a major participant in the inflammatory process and the complement activation component, C5a, is a potent inflammatory peptide. This study investigated the mRNA expression of the major receptor for C5a (C5aR; CD88) in histopathological samples of canine mammary tumors by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) using canine-specific primers for CD88. A total of seven canine mammary tumors (four malignant carcinomas, two benign mixed mammary tumors, and one myoepithelioma) and eight normal mammary glands were analysed. All the tumor samples expressed low levels of CD88 mRNA, while none of the normal mammary tissues showed any detectable expression. These preliminary results suggest that C5a-CD88 interaction may play a contributory role in the inflammatory response associated with mammary tumor development in dogs. Further studies investigating the mechanisms behind complement activation and C5a receptor expression in canine mammary tumors are warranted.

Glial cell transplantation using olfactory ensheathing cells (OECs) holds a promising approach for treating spinal cord injury (SCI). However, integration of OECs into the hostile acute secondary injury site requires interaction and response to macrophages. Immunomodulation of macrophages to reduce their impact on OECs may improve the functionality of OECs. Vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), known for their immunomodulatory and neuroprotective functions, have provided improved outcomes in SCI animal models. Thus, VEGF and PDGF modulation of the SCI microenvironment may be beneficial for OEC transplantation. In this in vitro study, the effect of VEGF and PDGF on macrophages in an inflammatory condition was tested. Combined VEGF + PDGF reduced translocation nuclear factor kappa B p65 in macrophages without altering pro-inflammatory cytokines. Further, the ability of OECs to phagocytose myelin debris was assessed using macrophage-conditioned medium. Conditioned medium from macrophages incubated with PDGF and combined VEGF + PDGF in inflammatory conditions promoted phagocytosis by OECs. The growth factor treated conditioned media also modulated the expression of genes associated with nerve repair and myelin expression in OECs. Overall, these results suggest that the use of growth factors together with OEC transplantation may be beneficial in SCI therapy.

No abstract