The Study Of Dendritic Cells After Allogeneic Hematopoietic Stem Cell Transplantation

Objective: (1) To compare the dendritic cells reconstitution after different allogeneic hematopoietic stem cell transplantation in early time and if allogeneic graft CD34+ cell dose correlated with dendritic cells reconstitution after transplantation; (2) To detect the peripheral blood dendritic cells subsets of the patients with aGVHD or cGVHD before and after GVHD, and studied the role of dendritic cells subsets in aGVHD and cGVHD. Methods: (1) From June 2004 to March 2005, Twenty-eight patients undergoing allo-HSCT were enrolled in this study. There were 16 patients who undergone normal HSCT, 8 patients who undergone Haploidentical HSCT and 4 patients who undergone Nonmyeloablative HSCT. Three-color immunofluorescence staining was performed to study the alteration of the percentage and absolute number in circulating peripheral blood dendritic cells subsets on day 14, day 30, day 60 after transplantation among three distinct type HSCT. (2) We taken the normal HSCT and Haploidentical HSCT patients as our research objects. We compared the percentage and absolute number of circulating peripheral blood dendritic cells subsets at early time transplantation by the allogeneic graft CD34+ cell dose between the patients who undergone normal HSCT and Haploidentical HSCT. (3) Three-color immunofluorescence staining was applied to study the alteration of the percentage and absolute number of circulating peripheral blood dendritic cells subsets of the patients with aGVHD or cGVHD before and after GVHD, and studied the role of dendritic cells subsets in aGVHD and cGVHD. Results: (1) The dendritic cells subsets number of myeloablative HSCT patients were very low. No difference was observed in the kinetics of DC1 and DC2 reconstitution between the normal HSCT group and Haploidentical HSCT group patients(P > 0.05). There was significant difference between myeloablative HSCT group and normal healthy individuals(P < 0.01). There was significantly different between the non-myeloablative HSCT group and the myeloablative HSCT group in the kinetics of DC1 and DC2 reconstitution(P < 0.05). The significant differences were not observed between the different time in each transplantation groups > 0.05). (2)The median number of CD34+ cell infused was 4.51 X 106/kg (2.75~8.39X 106/kg) . We averagely divided the patients into three groups by CD34+ cell dose. CD34+ cell dose of the first group was 2.75-4.30X 106/kg. The second group was 4.30-6.85 X 106/kg. The third group was 6.85~8.39X 106/kg. Therefore, we compared the early dendritic cell reconstitution of the three groups patients. There was no significant difference between the three group in different time after transplantation (P<0.05). (3) The percentage and number in circulating peripheral blood dendritic cells subsets of the patients with aGVHD were decreased compared with those beforeaGVHD. The percentage and absolute number of DC1 and DC2 has significant difference between the two groups(P<0.05). The percentage and absolute number of dendritic cells subsets were significantly lower in patients with aGVHD than in patients without aGVHD. There was significantly different in percentage and absolute number of DC2 between the two groups(P<0.05). There was significantly different between the pre-treatment and post-treatment in patients with aGVHD(P<0.05). (4) The percentages of DC1 and DC2 in patients with cGVHD were significantly higher than healthy subjects(P< 0.05). The percentage and absolute number of peripheral blood dendritic cells subsets of the patients with cGVHD significantly droped after treatments. There was significant difference between the pre-treatment and post-treatment (P<0.05). Conclusion: (1) The early reconstitution of dendritic cells subsets in Nonmyeloablative HSCT patients is earlier than the patients who undergone myeloablative HSCT. The early reconstitution of dendritic cells subsets in normal HSCT and Haploidentical HSCT patients were slower. (2)Allogeneic graft CD34+ cell dose did not correlate with dendritic cells reconstitution after transplantation. (3) The peripheral blood dendritic cells subsets of the patients with aGVHD was decreased during the period of aGVHD. (4) The number of DC 1 and DG2 was increased in patients with cGVHD.