The winning image in the category of Life Sciences of the 2022 ZEISS Microscopy Image Contest was submitted by Dr. Tagide deCarvalho of the University of Maryland, Baltimore County (USA). It shows tongue epithelial cells adjoined by several different species of bacteria which form a complex biofilm on the tongue’s surface. The sample has been stained with DAPI, acridine orange and calcofluor white and was acquired with the ZEISS LSM 900 confocal microscope with Airyscan detector.

The oral cavity has the second largest and diverse microbiota after the gut harboring over 700 species of bacteria. Understanding the oral microbiome in health and disease will give further directions in drug development and targeted therapies.

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  Oral bacteria

  
  

In addition to the imaging I perform for scientific collaborations and research studies, I take my own microscopy images from samples that I find in my personal environment.

Dr. deCarvalho is the director of the Keith R. Porter Imaging Facility at the University of Maryland, Baltimore County (UMBC). Researchers at UMBC use the ZEISS LSM 900 confocal microscope to image a variety of biological samples such as planaria, hippocampal neurons and yeast cells to non-biological materials like hydrogels.

Dr. deCarvalho was interested in observing her own oral microbiota. Acquiring this image was more challenging than her other work. She first had to find a combination of fluorescent dyes to mosaically stain the bacteria, which involved a lot of trial and error. Additionally, because these microbes are relatively small, the imaging parameters had to be optimized for higher spatial resolution. She used low melting point agarose with glycerol to immobilize the samples and a 63x objective to take a series of images at different focal planes, which were reconstructed into a single image for the final product.