Immunohistochemical identification of ACE-2 (SARS-COV II entry mechanism) in the gastrointestinal tract, kidney and lung of rhesus monkeys (Macaca mulatta) and squirrel monkeys (Saimiri sciureus)

Abstract

SARS-Cov-2 is a corona virus that causes COVID-19 disease, a viral infection responsible for the pandemic decreed by the World Health Organization in March 2020. Angiotensin-converting enzyme 2 (ACE-2) functions as the main receptor for SARS-Cov-2. The study aimed to detect the expression of ACE-2 in the gastrointestinal tract, kidney, and lung in the rhesus monkeys and squirrel monkeys. The sections from 18 rhesus monkey and 17 squirrel monkeys were incubated with rabbit polyclonal antibody to ACE2 (ab65863). In the lung of the rhesus monkeys, the presence of ACE-2 was noted in the bronchial mucosa of the respiratory epithelium. In the kidney, there was irregular in the proximal convoluted tubules. In the pyloric stomach, duodenum and in the large intestine it was observed on the surface of the lining epithelium. In the lung of the squirrel monkeys, this marking was present in both the ciliated cylindrical and goblet cell sof the bronchi. In the kidney light marking was observed along the surfasse of the cubic epithelium of the proximal convoluted tubules and in the renal glomerulus. No markings were observed throughout the stomach and intense staining was observed along the surfasse of the intestinal epithelium of the duodenum, jejunum and ileum, as well as in the intestinal glands. In our study, we can observe not able differences in the distribution of ACE2 between the two species of primates analysed. These differences must be considered in experimental studies on this disease, which continues to be a topic of notable importance for Public Health.