The last analyzed TLR9 showed a statistically significant increase in the percentage of analyzed subpopulations of lymphocytes showing its positive expression both in patients with CVID (9.14 times for CD4+TLR9+; 6.43 times for CD8+TLR9+; and 5.91 times for CD19 +TLR9+) and CLL (6.84-fold for CD4+TLR9+; 5.77-fold for CD8+TLR9+; and 5.20-fold for CD19+TLR9+) in relation to a group of healthy volunteers, as well as among themselves (Figure 9) (Table 3). Here, TLR9 is linked to common variable immunodeficiency.