Serum BAFF and APRIL levels in patients with autoimmune hemolytic anemia and their clinical significance.

B cell-activating factor of the tumor necrosis factor family (BAFF) and a proliferation-inducing ligand (APRIL) play crucial roles in B cell development, survival, and antibody production. Autoimmune hemolytic anemia (AIHA) is an acquired autoimmune disease that occurs when antibodies target autologous red blood cells. Here, we analyzed the serum levels of BAFF and APRIL and their respective clinical associations in patients with AIHA. Serum BAFF and APRIL levels in patients with AIHA were significantly higher (P < 0.01) than in healthy individuals. Serum BAFF and APRIL levels were significantly augmented in patients with lower hemoglobin levels (hemoglobin was <8 g/dL) and higher LDH activity (LDH > 480 IU/mL). Glucocorticoid treatment dramatically reduced serum levels of BAFF and APRIL. Thus, serum BAFF and APRIL levels may reflect the clinical activity of this disease. Our results indicate that analysis of serum concentrations of BAFF and APRIL potentially represents a useful tool for the assessment of AIHA disease activity and progression.

BAFF level increased in patients with autoimmune hemolytic anemia.

INTRODUCTION: BAFF (B-cell activating factor of the TNF family), an important regulator of B-cell, has been observed to be over-expressed in a variety of autoimmune diseases. Autoimmune hemolytic anemia (AIHA) is an acquired autoimmune disease occurred when antibodies directed against autologous red blood cells. We assessed serum levels of BAFF in AIHA patients with different serological characteristics. METHODS: Serum BAFF levels were measured in 44 AIHA patients with different direct antiglobulin test (DAT) results and 25 healthy controls. The correlation of BAFF expression with DAT results and serological characteristics was assessed. RESULTS: Serum levels of BAFF in AIHA patients were significantly higher than in healthy subjects (AIHA: 1382.7 ± 1412.8 pg/ml, healthy control: 725.0 ± 415.7 pg/ml, P = 0.0057). Serum BAFF levels were significantly higher in patients with IgG(+)C3(+) or IgG(+) than healthy controls (DAT: negative) (P = 0.012, 0.004, respectively). No significant correlations were presented between serum BAFF levels and four serological parameters: hemoglobine, percentage of reticulocyte, total serum bilirubin, and lactate dehydrogenase. CONCLUSIONS: AIHA patients present higher serum BAFF levels than healthy controls, especially for those of IgG(+)C3(+) DAT result. This might lead to a new approach of AIHA treatment.