In our study, in MLR-high CLL patients with poor prognostic factors, that is, increased expression of CD38 and ZAP-70 in leukemic cells, we observed a significantly lower percentage of nonclassical monocytes with intracellular TNF expression and a significantly higher percentage of intermediate monocytes with intracellular IL-10 expression, allowing us to see a correlation between the functional maturation of the circulating monocytes and the degree of disease progression. The gene discussed is ZAP70; the disease is B-cell chronic lymphocytic leukemia.