Biomaterials and immune system: cellular reactivity towards PTFE and Dacron vascular substitutes pointed out by the leukocyte adherence inhibition (LAI) test.

Thirty-eight patients affected by peripheral vascular insufficiency, and twelve healthy volunteers, were submitted to a cellular immunity test: LAI test, in which leukocytes fail to adhere to glass in contact with a sensitizing antigen. Patients were divided as follows: Class 1: Dacron+PTFE grafted patients, Class 2: Dacron, Class 3: PTFE, Class 4: controls. Total leukocytes, mononuclear cells, T and B lymphocytes were used as cellular populations. Finely minced Dacron and PTFE fabric vascular prostheses were employed as targets. This research showed that a T cellular immune-reactivity towards Dacron and PTFE respectively occurs in Dacron and PTFE grafted patients, and that reactivity is greater in case of Dacron. Wider researches are required to state the immune system role in fabric prostheses patency; at this regard, must be kept in mind that T lymphocytes release thrombogenic factors in course of cellular immune response.