Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2014 Apr 15;5(2):e00025-14. doi: 10.1128/mBio.00025-14

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

Copyright © 2014 St. John et al.

This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-ShareAlike 3.0 Unported license, which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original author and source are credited.

PMC Copyright notice

FIG 3 — B. pseudomallei travels along olfactory nerve bundles. Sagittal sections were immunolabeled with anti-B. pseudomallei antibodies (green) and stained with DAPI (blue), with some sections also showing neurons (OMP antibodies; red) or glia (S100β-DsRed; red). (A) In regions of OE showing extensive crenellation (arrows with tails), bacteria (arrow) were present in the adjacent NC. (B and C) Double-label fluorescence. (B) Anti-B. pseudomallei (green). (C) Anti-OMP (red) and anti-B. pseudomallei (green). There was no evidence of bacteria penetrating the crenellated OE (arrow with tail), although bacteria were occasionally observed in axon bundles within the LP. Immunolabeling with anti-OMP (red in panel C) showed that axons surrounding the bacteria within the bundles had degraded and left a partially open conduit. (D) A cross section through an olfactory nerve bundle; olfactory ensheathing cells (red) are morphologically intact despite the presence of B. pseudomallei (arrow) within the nerve bundle; three-dimensional animation is shown in Movie S1 in the supplemental material. (E and F) When bacteria (arrow) were present in nerve bundles within the lamina propria, the axons were degraded, with OMP immunolabeling (red) restricted to the periphery of the bundles (arrows with tails), leaving an open conduit. (G and H) Examples of intact nerve bundles (arrows with tails) that were not infected with bacteria even though the epithelium showed signs of crenellation. (I to K) In the large nerve projecting toward the nerve fiber layer of the olfactory bulb (OB), bacteria (arrows) were localized to regions where axons were absent and OMP immunolabeling was restricted to the periphery (arrows with tails); the arrow in panel I points to the region shown in panels J and K, which is a double-label image, with panel K showing the image without OMP immunolabeling. (L and M) Immunolabeling with antibodies against B. pseudomallei (L) and OMP (M). (L) In addition to labeling the rod-like bacteria, the anti-B. pseudomallei antibodies also specifically labeled numerous vesicles in the vicinity of the bacteria. (N to Q) Schematics summarizing the infection of the axon fascicles. (N) Sagittal view of uninfected olfactory region with axons (red) projecting from the epithelium toward the OB. (O) Close-up of the healthy olfactory epithelium (OE) and lamina propria (LP) with OECs surrounding the axons in the LP. (P) In uninfected mice, some axons are degraded (arrow) and bacteria (green) migrate along the empty nerve fascicles. (Q) Close-up view demonstrating how the bacteria migrate along the empty nerve fascicles within the confines of the surrounding OECs. Bar sizes are in μm.