Human IgM Inhibits the Formation of Titan-Like Cells in Cryptococcus neoformans.

ABSTRACT: Human studies have shown associations between cryptococcal meningitis and reduced IgM memory B cell levels, and studies in IgM- and/or B cell-deficient mice have demonstrated increased Cryptococcus neoformans dissemination from lungs to brain. Since immunoglobulins are part of the immune milieu that C. neoformans confronts in a human host, and its ability to form titan cells is an important virulence mechanism, we determined the effect of human immunoglobulins on C. neoformans titan cell formation in vitro (i) Fluorescence microscopy showed normal human IgG and IgM bind C. neoformans (ii) C. neoformans grown in titan cell-inducing medium with IgM, not IgG, inhibited titan-like cell formation. (iii) Absorption of IgM with laminarin or curdlan (branched and linear 1-3-beta-d-glucans, respect

SUBMITTER: Trevijano-Contador N 

PROVIDER: S-EPMC7093138 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature