High percentage of regulatory T cells before and after vitamin B12 treatment in patients with pernicious anemia.

INTRODUCTION: In some previous studies, vitamin B12 treatment showed immunomodulatory effects and restored the immunological abnormalities in patients with pernicious anemia (PA). In the present study, peripheral blood T cell subsets, including regulatory T cells (T(reg)s), were examined before and after vitamin B12 treatment in PA patients. PATIENTS AND METHODS: The percentages of CD4, CD8, Th1, Th2 and T(reg)s were examined in 23 PA patients before vitamin B12 treatment, in 23 other PA patients after vitamin B12 treatment and in 28 healthy controls. RESULTS: The mean percentage of CD8+ T cells was significantly higher in the control group (23.0%; 95% CI, 20.4-25.6%) than in the pre- (16.0%; 95% CI, 12.1-20.0%) and posttreatment groups (15.2%; 95% CI, 11.8-18.6%; p < 0.05). The CD4/CD8 ratio was significantly lower in the control group (2.01; 95% CI, 1.66-2.34) than in the pre- (3.45; 95% CI, 2.55-7.80) and posttreatment groups (2.97; 95% CI, 2.22-3.72; p < 0.05). There was no significant difference in the mean Th1/Th2 ratio among these groups. There were significant increases in the mean percentage of T(reg)s in the pre- (6.29%; 95% CI, 5.04-7.54%) and posttreatment groups (7.77%; 95% CI, 6.34-9.20%) compared with the control group (4.18%; 95% CI, 3.92-4.47%; p < 0.05). CONCLUSIONS: The percentage of T(reg)s was significantly higher in PA patients than in normal subjects, and this high T(reg) percentage was not different before and after vitamin B12 treatment. Other immunological alterations also did not recover after vitamin B12 treatment, so that these immunological changes appear to be the cause of PA and are not induced by vitamin B12 deficiency.

[Improvement in peripheral blood T cell subset imbalance in a house with an elimination system for various allergens].

We analyzed the change of peripheral blood T cell subsets after moving into a house with a Healthy Air system (HAS) elimination system for various allergens, e.g. pollens, house dusts, etc. The 20 subjects were divided into an allergic group (13 subjects) and control group (7 subjects). We measured complete blood counts (CBC), white blood cell differentiation (DIFF), CD4/CD8 ratio, Th1/Th2 ratio, and percentage of CD4+CD25+T-cells and regulatory T-cells in peripheral blood, and these data were compared before and 3 and 6 months after moving into the HAS house. There was no significant difference in CBC, DIFF, CD4/CD8 ratio, and Th1/Th2 ratio before and after the move. The mean levels and 95% confidence interval of CD4+CD25+T-cells in the allergic group were as follows: before, 16.66% (12.99-20.34%); at 3 months, 13.86% (10.49-17.22%); and at 6 months, 12.66% (9.28-16.05%), respectively. Those in the control group were as follows: before, 13.60% (5.27-21.93%); at 3 months, 12.51%(5.41-19.61%); and at 6 months, 11.77% (3.93-19.61%), respectively. CD4+CD25+T-cells were significantly decreased at 6 months after the move compared to before the move in the allergic group (p < 0.01). However, there was no significant difference between before and after the move in the control group. The mean levels of regulatory T-cells were not different between before and after the move in both groups. The mean level of CD4+CD25+T-cells in subjects that had improved allergic condition was significantly decreased at 6 months after the move compared to before the move (p < 0.05). These results suggest that decreases in allergens in the home environment may affect lymphocyte subsets.