Universities have a key role to play in the progress and development of the Knowledge Society. They should lead the way in the design of teaching strategies that promote knowledge building. Personal learning environments (PLE) represent a groundbreaking new development in educational practices through the incorporation of Information and Communications Technology (ICT), and an opportunity to promote the creation of universities without walls able to meet the demands of the knowledge society. This study focuses on the relationships established by the participants (students and teachers) in two higher education instructional sequences using institutionally-powered PLE (iPLE). One of the sequences was carried out at the University of Barcelona and the other at the University of Andorra. Both used the same technological support, the "Elgg" platform, which allows users to build their own personal work and learning environment. The main hypothesis of the study is that the relationships formed depend on the techno-pedagogical design of the teaching and learning process. The results show that in both cases the relationships that the participants establish with their peers and teachers are indeed related to the characteristics and requirements of the particular techno-pedagogical designs. Although the technological environment allowed all the participants to establish relationships with others, the main interactions were found in small working groups created to carry out learning and assessment activities. In conclusion, we stress the importance of planning teaching and learning activities and assessment processes that are able to exploit the full potential of PLE.