Lipopolysaccharides from Microcystis Cyanobacteria-Dominated Water Bloom and from Laboratory Cultures Trigger Human Immune Innate Response

Abstract

Massive toxic blooms of cyanobacteria represent a major threat to water supplies worldwide. Here, the biological activities of lipopolysaccharide (LPS) isolated from Microcystis aeruginosa, the most prominent cyanobacteria in water bloom, were studied. LPS was isolated from complex environmental water bloom samples dominated by M. aeruginosa, and from laboratory cultures of non-axenic as well as axenic M. aeruginosa strains PCC7806 and HAMBI/UHCC130. Employing human blood-based in vitro tests, the LPS isolated from complex water bloom revealed the priming of both major blood phagocyte population monocytes and polymorphonuclear leukocytes documented by the increased surface expression of CD11b and CD66b. This was accompanied by a water bloom LPS-mediated dose-dependent induction of tumor necrosis factor α, interleukin-1β, and interleukin-6 production. In accordance with its priming effects, water bloom LPS induced significant activation of p38 and ERK1/2 kinases, as well as NF-κB phosphorylation, in isolated polymorphonuclear leukocytes. Interestingly, the pro-inflammatory potential of LPS from the axenic strain of M. aeruginosa was not lower compared to that of LPS isolated from non-axenic strains. In contrast to the biological activity, water bloom LPS revealed almost twice higher pyrogenicity levels compared to Escherichia coli LPS, as analyzed by the PyroGene test. Moreover, LPS from the non-axenic culture exhibited higher endotoxin activity in comparison to LPS from axenic strains. Taking the above findings together, M. aeruginosa LPS can contribute to the health risks associated with contamination by complex water bloom mass.

Effects of Dietary Ferulic Acid on the Intestinal Microbiota and the Associated Changes on the Growth Performance, Serum Cytokine Profile, and Intestinal Morphology in Ducks

“…Additionally, members of family bacilli , including the Gram-negative bacilli were among the most common causative agents of infectious diseases, and triggers of the inflammation ( Dandachi et al, 2019 ). Phylum Cyanobacteria were reported to be immune suppressing ( Gemma et al, 2016 ), but some members in Cyanobacteria , for example Microcystis aeruginosa , whose lipopolysaccharide could trigger human immune response ( Moosová et al, 2019 ). Moreover, phylum Elusimicrobia were proved to be positively correlated to multiple proinflammatory cytokines and promoted the occurrences of immunological stress in colitis rats ( Tao et al, 2017 ), which was in line with our finding.…”

Effects of cyanobacterial toxins on the human gastrointestinal tract and the mucosal innate immune system

“…Although the effects of Escherichia coli LPS are stronger, LPS from blooms and cultured strains of M. aeruginosa as well activates NF-κB in human immune cells and subsequently leads to the production and release of pro-inflammatory cytokines [157,158]. On the other hand, LPS have also showed anti-inflammatory properties.…”

“…These immune cells express TLR4 and can be activated by LPS crossing the mucosal/epithelial barrier due to the increased permeability of inflamed epithelia [167]. In vitro studies show for example that LPS from M. aeruginosa blooms and strains activates blood cells, namely human polymorphonuclear leukocytes and monocytes, which are involved in the innate immune defense [157,158]. Furthermore, rat microglia were shown to be activated by LPS from different cyanobacterial species [173][174][175].…”

Anabaenopeptins: What We Know So Far

“…Cyanotoxins are among the most studied compounds originated from cyanobacteria since they are capable of negatively affecting human and animal health [ 4 , 5 ]. These metabolites can vary drastically concerning their action mechanism and chemical structure, which include peptides, alkaloids, and lipopolysaccharides [ 6 , 7 , 8 ]. The majority of publications related to peptides from cyanobacteria have mainly focused on the class of microcystins with over 300 characterized variants [ 9 , 10 ].…”