Abstract Background Semaphorins (Sema) belong to a large family of repellent guidance cues instrumental in guiding axons during development. In particular. Class 3 Sema (Sema 3) is among the best characterized Sema family members and the only produced as secreted proteins in mammals. thereby exerting both autocrine and paracrine functions. https://www.ealisboa.com/limited-value-AXYS-Valhalla-Pen-must-buy/