Safety Studies of Pneumococcal Endolysins Cpl-1 and Pal
Marek Harhala,
Daniel C. Nelson,
Paulina Miernikiewicz,
Ryan D. Heselpoth,
Beata Brzezicka,
Joanna Majewska,
Sara B. Linden,
Xiaoran Shang,
Aleksander Szymczak,
Dorota Lecion,
Karolina Marek-Bukowiec,
Marlena Kłak,
Bartosz Wojciechowicz,
Karolina Lahutta,
Andrzej Konieczny,
Krystyna Dąbrowska
Affiliations
Marek Harhala
Bacteriophage Laboratory, Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla Street 12, 53-114 Wroclaw, Poland
Daniel C. Nelson
Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, USA
Paulina Miernikiewicz
Bacteriophage Laboratory, Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla Street 12, 53-114 Wroclaw, Poland
Ryan D. Heselpoth
Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, USA
Beata Brzezicka
Bacteriophage Laboratory, Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla Street 12, 53-114 Wroclaw, Poland
Joanna Majewska
Bacteriophage Laboratory, Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla Street 12, 53-114 Wroclaw, Poland
Sara B. Linden
Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, USA
Xiaoran Shang
Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850, USA
Aleksander Szymczak
Bacteriophage Laboratory, Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla Street 12, 53-114 Wroclaw, Poland
Dorota Lecion
Bacteriophage Laboratory, Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla Street 12, 53-114 Wroclaw, Poland
Karolina Marek-Bukowiec
Research and Development Center, Regional Specialized Hospital, 51-124 Wrocław, Poland
Marlena Kłak
Research and Development Center, Regional Specialized Hospital, 51-124 Wrocław, Poland
Bartosz Wojciechowicz
Perlan Technologies Sp. z o. o., 02-785 Warsaw, Poland
Karolina Lahutta
Bacteriophage Laboratory, Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla Street 12, 53-114 Wroclaw, Poland
Andrzej Konieczny
Research and Development Center, Regional Specialized Hospital, 51-124 Wrocław, Poland
Krystyna Dąbrowska
Bacteriophage Laboratory, Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla Street 12, 53-114 Wroclaw, Poland
Bacteriophage-derived endolysins have gained increasing attention as potent antimicrobial agents and numerous publications document the in vivo efficacy of these enzymes in various rodent models. However, little has been documented about their safety and toxicity profiles. Here, we present preclinical safety and toxicity data for two pneumococcal endolysins, Pal and Cpl-1. Microarray, and gene profiling was performed on human macrophages and pharyngeal cells exposed to 0.5 µM of each endolysin for six hours and no change in gene expression was noted. Likewise, in mice injected with 15 mg/kg of each endolysin, no physical or behavioral changes were noted, pro-inflammatory cytokine levels remained constant, and there were no significant changes in the fecal microbiome. Neither endolysin caused complement activation via the classic pathway, the alternative pathway, or the mannose-binding lectin pathway. In cellular response assays, IgG levels in mice exposed to Pal or Cpl-1 gradually increased for the first 30 days post exposure, but IgE levels never rose above baseline, suggesting that hypersensitivity or allergic reaction is unlikely. Collectively, the safety and toxicity profiles of Pal and Cpl-1 support further preclinical studies.
