mAb binds GIPLs and the surface of amastigotes, and induces IL-10 from macrophages.

<p><b><i>A</i></b>. A newly developed mAb (26H3T-B4) was bound to <i>L. mexicana</i> axenic amastigotes at varying amounts per 10⁶ axenic amastigotes and detected using PE-goat anti-mouse IgG by flow cytometry, with geometric mean fluorescence intensity (GMFI) calculated for samples in triplicate; a mouse IgG1 isotype control was used at the same concentrations (isotype ctrl). Triplicate samples with no antibody (no Ab) are shown with a line for comparison. At all concentrations, GMFI were different for 26H3T-B4 vs. isotype control; GMFI for 26H3T-B4 were also different from no antibody controls. <i>P</i><0.02 for all comparisons. <b><i>B</i></b>. Biotinylated 26H3T-B4 was tested for GIPL binding by ELISA at varying concentrations. <b><i>C</i></b>. Bone marrow-derived macrophages were incubated in media alone, or stimulated with lipopolysaccharide (LPS), <i>L. mexicana</i> axenic amastigotes+LPS (a.a.+LPS), or amastigotes opsonized with 26H3T-B4+LPS (26H3T-B4 ops a.a.+LPS), and then supernatants were assayed for IL-10 by ELISA. *, <i>P</i><0.004 for all comparisons. Data represent at least 2 experiments with similar results.