Peripolesis

Peripolesis is thought to be a physiological mechanism involved in regulating some processes of immune response.

It was observed between lymphocytes and macrophages following skin grafts between subjects, and after immune challenge with antigens.

[1] Peripolesis was also observed in lung alveoli, where the peripolesed macrophages were not injured, but the cell membrane did appear to be temporarily altered.

[2] In patients with active sarcoidosis, which is characterized by lymphocyte-macrophage cooperation, lymphocyte peripolesis appeared to occur in clusters and could last for minutes to hours.

The lymphocytes could be seen moving around a macrophage while maintaining contact.