ABSTRACT. The immunotherapies, as a modern therapeutic approach, get an attention because of theirs’ promise to treat a large number of different medical disorders. Immunomodulation effects of low titres (10 HA/ml) of NDV (Newcastle Disease Virus) ZG1999HDS or La Sota were tested on TLT (Human macrophage cell line) bound to PBMC (Peripheral Blood Mononuclear Cells). During the immunomodulation, the amount of NO, H2O2, lysozym and induced antibacterial activity against Gram - positive bacteria (Staphylococcus aureus, MRSA, Streptococcus pyogenes, Streptococcus agalactiae and Streptococcus mutants) and against Gram - negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis and Acinetobacter baumanii) were analysed. In addition, the cytokine secretion, IL-1α, IL-2, IL-4, GM-CSF, TNF-α, IFN-α and IFN-α were evaluated. Firstly, the TLT cells are activated through the NDV ZG1999HDS or La Sota binding, followed by the NO “burst” and H2O2 and lysozyme level increase. Secondly, after the binding to the TLT cells and interaction with the PBMCs, the decrease of GM-CSF, and an increase of TNF – α and IFN – γ were found. Simultaneously, the decrease of pro – inflammatory cytokine IFN-α and the differentially increase of IL-1α, IL-2 and IL-4 were recorded. During the induction of the antibacterial response, against Gram - positive bacteria (Staphylococcus aureus, MRSA, Streptococcus pyogenes, Streptococcus agalactiae and Streptococcus mutants) the effect was one third higher with NDV ZG1999HDS compared to La Sota. Antibacterial response against Gram - negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis and Acinetobacter baumanii) was not so clear. In general, NDV ZG1999HDS or La Sota activated TLT cells, further bound to PBMC; the ZG1999HDS is stronger immunomodulator than La Sota.