Fixation on Histology

ALS and Identifying Bunina Bodies


Amyotrophic lateral sclerosis (ALS), more commonly known as ALS, is a deadly and devastating disease that impacts approximately 30,000 people in the U.S. with no known cure. ALS is identified by several characteristics, but perhaps none are more specific than Bunina Bodies.

In 1962, neuropathologist Tat’yana Bunina was conducting research on ALS and, while studying the disease in primates, she observed and described inclusion bodies with almost identical morphology in the spinal cords and brain stems of two cases of familial ALS. Her observations led to the further discovery that these structures were pathologically specific to ALS, and these important structures are now named Bunina Bodies, or BBs. Their presence suggests underlying mechanisms of protein misfolding, aggregation, and impaired proteostasis, which are central to the pathophysiology of ALS.

Bunina Bodies are found in the motor neurons of the spinal cord and the brainstem nuclei . Microscopically, they can be found in the cytoplasm and dendrites, and when stained with H&E, they appear bright pink (Figure 1). Bunina Bodies consist of amorphous electron-dense material surrounded by tubular and vesicular structures on electron microscopy.

Figure 1

By studying the composition and formation of Bunina Bodies, researchers can learn more about the disease's progression and the role of various proteins in ALS pathology, potentially leading to the identification of new therapeutic targets.

Learn more about ALS in this interview with the 2024 NSH Culling Memorial Lecturer, David Krull, who will be giving his talk “The Histology of ALS” on September 23, 2024, at the annual NSH Convention in New Orleans, LA.  (Oh, and don’t forget to register, Advanced rates end July 15th!)


  4. Rowland, L. P. (2009). T.L. Bunina, Asao Hirano, and the post mortem cellular diagnosis of amyotrophic lateral sclerosis. Amyotrophic Lateral Sclerosis10(2), 74–78.

Written by: Connie Wildeman, MPA, Director of Education, NSH