Preliminary study of "erythroblast island" in the bone marrow of hematocytopenic patients with positive BMMNC-Coombs test / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the mechanism of 'erythroblast island (EI)' formation in the bone marrow of patients with immun-related hemocytopenia (IRP).</p><p><b>METHODS</b>The category of BM-auto antibody (au Ab) in 48 patients with IRP was detected with FCM. The BM-au Ab in the 'EI' of these cases were explored with immuonhistofluorescence (IF). Clinical and laboratory characteristics of these cases were also analyzed retrospectively.</p><p><b>RESULTS</b>IgG could be detected in the 'EI' on the BM smear of 14 cases (29.17%), BM-au Ab mainly deposited at the edge/membranes between macrophage and erythroblasts rather than cyto plasm. Positive reaction were seen in all the cases with GlycoAIgG. The red blood cell count [(1.8 ± 0.5) × 10(12)/L] and hemoglobin level [(59.6 ± 16.2)g/L] were significantly lower than that in the IF(-) group [(2.5 ± 0.9) × 10(12)/L and (83.4 ± 25.0) g/L] (P < 0.05). The percentage of reticulocyte [(2.0 ± 0.8)%], serum level of IBIL [(9.4 ± 4.7) µmol/L], percentage of erythroblats in sternum BM (0.441 ± 0.139) and response rate to therapy (85.7%) in IF(+) group were significantly higher than that in IF(-)group [(1.3 ± 1.0)%, (6.6 ± 6.7)µmol/L, 0.298 ± 0.082, 61.3%, respectively] (P < 0.05).</p><p><b>CONCLUSION</b>Macrophage was connected with erythroblasts through autologous IgG in the 'EI's of some patients with IRP. 'EI' were the places where macrophages devoured and destroyed erythroblasts rather than erythroid development and differentiation. The pathogenetic mechanism of IRP might be associated with macrophages phagocytosing and destroying BM hematopoietic cells.</p>

Study on the dendritic cell subsets in peripheral blood and its relationship with the expressions of T-bet and GATA-3 in lymphocytes in severe aplastic anemia / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the dendritic cell (DC) subsets and transcriptive factors, T-bet, GATA-3, and immune imbalance in acquired severe aplastic anemia (SAA).</p><p><b>METHODS</b>The DC1 (HLA-DR+Lin-CD11c+) and DC2 (HLA-DR+Lin-CD123+) in peripheral blood mononuclear cells (PBMNC) were measured with flow cytometry (FCM), the expressions of T-bet mRNA and GATA-3 mRNA in PBMNC with semiquantitative RT-PCR and the plasma level of IFN gamma and IL-4 with ELISA in 29 SAA patients and 16 healthy controls.</p><p><b>RESULTS</b>The percentages of DC1 in PBMNC were (0.44 +/- 0.24)% and (0.73 +/- 0.30)% in untreated and recovered SAA patients respectively, both were higher than that in controls (0.29 +/- 0.10)% (P < 0.05). The percentage of DC2 in the untreated cases was lower than that of recovered ones or controls [(0.18 +/- 0.14)% vs (0.28 +/- 0.20)% and (0.29 +/- 0.13)%] (P < 0.05). DC1/DC2 ratios were 3.45 +/- 2.71 and 2.90 +/- 0.95 in untreated and recovered groups respectively, both were higher than that in controls (1.15 +/- 0.56) (P < 0.05). No statistic difference in DC1/DC2 ratio was found between untreated and recovered patients (P < 0.05). The relative mRNA expression levels of transcriptive factor T-bet were 0.37 +/- 0.07, 0.20 +/- 0.07 and 0.17 +/- 0.05 in the above 3 groups, respectively, untreated group being higher than that of recovered group or healthy controls (P < 0.05). There was no statistic difference of GATA-3 expression among the 3 groups (P > 0.05). T-bet/GATA-3 ratio was 0.72 +/- 0.13 in untreated group, being higher than that of recovered group (0.33 +/- 0.08) or controls (0.35 +/- 0.11). The plasma level of IFN gamma in the untreated group was (50.9 +/- 1.1) ng/L, which was higher than that of recovered group [(49.7 +/- 0.9) ng/L] or controls [(49.7 +/- 0.7) ng/L]. There was significant positive correlations between T-bet and DC1/DC2 ratio (r = 0.445, P < 0.01), as well as between T-bet and IFN gamma (r = 0.402, P < 0.01).</p><p><b>CONCLUSION</b>Either DC1/DC2 or T-bet/GATA-3 ratio might become an index to estimate immune imbalance. High-expressed T-bet was related to the progress of SAA. In patients with SAA, DC1/DC2 ratio returns to normal range later than that of routine blood test does, indicating that immunosuppressive therapy should not be withdrawn too earlier.</p>