Figure 2. Morphological abnormalities in E15 brains exposed to murine anti-NMDAR AAbs in utero.
The monoclonal AAb R4A or the control IgG2b was intravenously administered to pregnant dams (200 μg per dam), at E12. Embryos were harvested at E15 for analysis. Coronal sections of E15 fetal brains were stained with PH3, DAPI and nestin. (a) R4A shows reactivity to MP (peptide) and double-stranded DNA (dsDNA) by ELISA (mean ± s.d., ** P < 0.0001, Mann-Whitney U test). (b) Mitotic activity is assessed with PH3 expression. The VZ harbors most PH3+ cells (single arrows) in both groups, but PH3+ cells are found outside of the VZ in R4A-exposed neocortex (double arrows). (c) VZ and (SVZ) of R4A-exposed fetal brains show significantly more PH+ cells (mean ± s.d., ** P < 0.0001, Mann-Whitney U test). (d) Combined DAPI/nestin stained sections of R4A or IgG2b neocortex are used to measure the CP (arrows in the merged panels). Fetal brains exposed to R4A in utero show CP thinning. (e) CP thickness is significantly decreased in the neocortex exposed to R4A (P < 0.0001, Mann-Whitney U test). CP to CW ratio is significantly reduced in R4A-treated neocortex (mean ± s.e.m., ** P < 0.0001, Mann-Whitney U test), demonstrating that passive transfer of R4A from maternal circulation to the fetal neocortex disrupts proper development of the CP. For each assay, 2 fetal brains per dam were analyzed; n = 3 dams for each group. Scale bar = 250 μm.