In the category “immune system helpers”, we pooled all the trials that tested vaccines, antibodies or immunoglobulins, generally used as a preventive approach to avoid infections. Vaccines are the most recurrent result, representing 55.6% of the total items found.
It is worthy of note that not a single basic research review on vaccines was retrieved using the two keywords (“biofilm” and “bacterial infections”), although a search on Pubmed.gov using the keyword “vaccine” to be included in study title results in more than 1,500 reviews over the past five years. This observation suggests that vaccines are not investigated as a strategy against biofilms, at least in reviews published in this time period.
Alternatively, this can be a limitation of the searching criteria used.
Interestingly, some solutions are gaining attention in the clinical trials, such as the possibility to use biofilm structural moieties to prepare specific antibiofilm vaccines. Specifically, Gil et al, 2014 describe an in vivo model where mice are immunized by Staphylococcus aureus biofilm matrix exoproteome. This significantly reduced the number of bacterial cells inside a biofilm and on the surrounding tissue [i]. Other authors, such as Rafaat et al, 2019, describe the use of monoclonal antibodies to fight S. aureus both in preclinical and clinical studies [ii,iii].
Gil, C.; Solano, C.; Burgui, S.; Latasa, C.; García, B.; Toledo-Arana, A.; Lasa, I.; Valle, J. Biofilm matrix exoproteins induce a protective immune response against Staphylococcus aureus biofilm infection. Infect. Imm. 2014, 82(3): 1017-1029.
Raafat, D.; Otto, M.; Reppschläger, K.; Iqbal, J.; Holtfreter, S. Fighting Staphylococcus aureus biofilms with monoclonal antibodies. Trends Microbiol. 2019, 27(4), 303-322.
Speziale, P.; Rindi, S.; Pietrocola, G. Antibody-based agents in the management of antibiotic-resistant Staphylococcus aureus diseases. Microorganisms. 2018, 6(1), 25.