Clinical determinants that were associated with higher binding and neutralizing Ab titers included early Rai stage disease (0–II), low serum β2-microglobulin (≤2.4 mg/L) levels, lack of prior CLL therapy, vaccination ≥12 months following anti-CD20 therapy, and no requirement for IVIg therapy (all p ≤ 0.04; Table 3). The gene discussed is HLA-G; the disease is B-cell chronic lymphocytic leukemia.