Immunological aspects of juvenile periodontitis (periodontosis)

Cell‐mediated and humoral immunological investigations were carried out in 34 patients with advanced destructive periodontal disease. In 23 of these patients, 14 to 21 years old, juvenile periodontitis was diagnosed by clinical and radiological criteria. Stimulation of lymphocyte transformation by autologous plaque, Veillonella alcalescens, Fusobacterium fusiforme and Bacteroides melaninogenicus was impaired, the response to Actinomyces viscosus was intact, but those to unrelated antigens, such as purified protein derivative (PPD) or Herpes simplex virus type 1 (HSV1) and to phytohaemagglutinin (PHA), were enhanced. However, lymphocytes stimulated by these antigens relased a factor causing macrophage migration inhibition in up to 65 % of patients. Substititution of autologous serum by homologous or fetal calf serum did not increase lymphocyte transformation, but was associated with conversion of the negative to positive macrophage migration inhibition activity, so that the latter was found in 80 % to 100 % of patients. Serum IgM, IgG and IgA concentrations were significantly increased and the haemagglutinating titres to related bacteria were higher than those found in controls. Comparable cell‐mediated and humoral immune responses were found in 11 patients, 22 to 29 years old, whose clinical and radiological features were similar to those in patients with juvenile periodontitis; the disease in these patients can be referred to as ‘post‐juvenile periodontitis’. The results suggest that in juvenile periodontitis a selective impairment of antigen induced DNA synthesis of lymphocytes to plaque and some Gramnegative organisms, is associated with release of macrophage migration inhibition factor.