Impact of Polyvalent Mechanical Bacterial Lysate on lymphocyte number and activity in asthmatic children: a randomized controlled trial

BACKGROUND: Polyvalent Mechanical Bacterial Lysate (PMBL®) contains antigens of bacteria responsible for respiratory infections. PMBL® has been proven to reduce the number of respiratory infections, and in its use, immunological benefits have been seen in allergic patients. PMBL® activates both innate and specific immune responses. The lysate induces dendritic cells, T and B lymphocytes and IgA secretion, as well as the production of antibodies directed against administered bacterial antigens. Moreover, it increases the response against other bacteria and viruses. The immunologic mechanism of lysate’s action is not yet clearly determined. The objective of this study was to assess the effect of PMBL® on T cells in children with allergic asthma. METHODS: This study was a part of the EOLIA study. Herein, 49 children with allergic asthma and house dust mites allergy were included: 21 in PMBL® and 28 in the Placebo group, both, drug and placebo were administered sublingually. The tests were done at baseline and 12 weeks after the last tablet intake. The lymphocytes CD45+, lymphocytes T CD3+, CD3+CD25+, CD3+CD69+, Th CD3+CD4+, CD4+CD25+, CD4+CD25+ high, CD4+CD69+, Treg CD4+CD25+FOXP3, Tc CD3+CD8+, CD8+CD25+, CD8+CD69+, NK-like T CD3+CD16+CD56+ and NK cells CD3−CD16+CD56+ were described. RESULTS: At baseline, no significant differences between groups relative to blood count cells were observed, except for eosinophils. After 12 weeks, we observed an increase of T lymphocytes count. In addition, CD4+CD25+FOXP3+, CD8+ and CD3−CD16+CD56+ and (insignificantly) Th count increased. However, CD69+ and CD25+ subset of CD3+ significantly decreased. CONCLUSIONS: The EOLIA study demonstrated that PMBL® administration 10 days per month for 3 months changed the panel of T lymphocytes. Trial registration Clinical Trial Registration: This study was a part of the EOLIA (Efficacy Of mechanical bacterial Lysate In Allergic children), a clinical study NCT02541331. Frederic Durmont, MD Lallemand Pharma International AG. Date of registration 09/08/2013. URL of trial registry record: https://clinicaltrials.gov/ct2/show/study/NCT02541331.