Open AccessHuman serum proteins bind to Sporothrix schenckii conidia with differential effects on phagocytosis
Author(s) -
Silvia Guzman Beltrán,
Jazmín Sanchez Morales,
Augusto González-Canto,
Alma Escalona Montaño,
Haydée Torres Guerrero
Publication year - 2020
Publication title -
brazilian journal of microbiology
Language(s) - English
Resource type - Journals
eISSN - 1678-4405
pISSN - 1517-8382
DOI - 10.1007/s42770-020-00276-3
Subject(s) - phagocytosis , transferrin , mannose receptor , transferrin receptor , sporothrix schenckii , microbiology and biotechnology , biology , human serum albumin , conidium , blood proteins , innate immune system , sporotrichosis , chemistry , macrophage , immune system , biochemistry , immunology , in vitro , botany
Serum is an important source of proteins that interact with pathogens. Once bound to the cell surface, serum proteins can stimulate the innate immune system. The phagocytosis of Sporothrix schenckii conidia by human macrophages is activated through human serum opsonisation. In this study, we have attempted to characterise human blood serum proteins that bind to the cell wall of S. schenckii conidia. We systematically observed the same four proteins independent of the plasma donor: albumin, serum amyloid protein (SAP), α-1 antitrypsin (AAT), and transferrin were identified with the help of tandem mass spectrometry. Phagocytosis depended on the concentration of the SAP or α-1 antitrypsin that was used to opsonise the conidia; however, transferrin or albumin did not have any effect on conidia internalisation. The presence of mannose did not affect macrophage phagocytosis of the conidia opsonised with SAP or α-1 antitrypsin, which suggests that these proteins are not recognised by the mannose receptor.