Immunologic Effects of Sirolimus in Patients With Vascular Anomalies.

Emerging data have suggested that sirolimus may be a treatment option for complicated vascular anomalies (VAs). The present study aimed to investigate the immunologic effects of sirolimus treatment for 6 months in patients with VAs. Blood samples obtained from the patients enrolled in 2 multicenter studies to investigate the efficacy of sirolimus for VAs before and after sirolimus treatment for 6 months were used. Data for total white blood cell count, absolute lymphocyte count, serum immunoglobulins (Igs) levels (IgG, IgA, IgM), lymphocyte proliferation assays with mitogens including phytohemagglutinin and concanavalin A, and flow cytometric analysis of lymphocyte subsets were evaluated. A total of 18 patients with VAs receiving sirolimus treatment were included in the study. Comparisons of white blood cell, absolute lymphocyte count, IgG, IgA, IgM, and reaction rates of phytohemagglutinin and concanavalin A revealed no significant differences before and after treatment. No significant differences were observed in the absolute counts of lymphocyte subtypes before and after treatment, except for regulatory T-cell counts, which were significantly decreased after treatment. Severe infections were not observed during sirolimus treatment. The immunologic parameters assessed in the present study were hardly affected by sirolimus treatment for 6 months in patients with VAs.

Expression of CD34 and CD105 as markers for angiogenesis in oral vascular malformations and pyogenic granulomas.

The objective of this study was to assess angiogenic activity by analyzing anti-CD105 and anti-CD34 immunostaining in 20 cases of vascular malformations (VMs) and 20 cases of oral pyogenic granulomas (OPG). In addition, the usefulness of these markers for the differential diagnosis of these two oral tumors was evaluated. The results showed no significant difference in mean microvessel count between the anti-CD105 (P = 0.803) and anti-CD34 (P = 0.279) antibody. The mean number of vessels was 18.75 and 59.72 for oral VMs immunostained with anti-CD105 and anti-CD34 antibody, respectively, whereas in OPG the mean number was 20.22 and 48.09, respectively. CD34 was found to be more effective than CD105 in identifying blood vessels. However, the anti-CD105 antibody seems to be more related to vascular neoformation. Overall, this study supports the role of angiogenic factors in the etiopathogenesis of oral VMs and PG, but the results showed that quantification of angiogenesis cannot be used as a marker for the differential diagnosis of these two types of lesions.