AUTHOR=Saniee Parastoo , Siavoshi Farideh 

TITLE=Endocytotic uptake of FITC-labeled anti-H. pylori egg yolk immunoglobulin Y in Candida yeast for detection of intracellular H. pylori

JOURNAL=Frontiers in Microbiology

VOLUME=6

YEAR=2015

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2015.00113

DOI=10.3389/fmicb.2015.00113

ISSN=1664-302X

ABSTRACT=<p>Intracellular life of <italic>Helicobacter pylori</italic> inside <italic>Candida</italic> yeast vacuole describes the establishment of <italic>H. pylori</italic> in yeast as a pre-adaptation to life in human epithelial cells. IgY-Hp conjugated with fluorescein isothiocyanate (FITC) has been previously used for identification and localization of <italic>H. pylori</italic> inside the yeast vacuole. Here we examined whether FITC-IgY-Hp internalization into yeast follows the endocytosis pathway in yeast. Fluorescent microscopy was used to examine the entry of FITC-IgY-Hp into <italic>Candida</italic> yeast cells at different time intervals. The effect of low temperature, H<sub>2</sub>O<sub>2</sub> or acetic acid on the internalization of labeled antibody was also examined. FITC-IgY-Hp internalization initiated within 0–5 min in 5–10% of yeast cells, increased to 20–40% after 30 min–1 h and reached &gt;70% before 2 h. FITC-IgY-Hp traversed the pores of <italic>Candida</italic> yeast cell wall and reached the vacuole where it bound with <italic>H. pylori</italic> antigens. Internalization of FITC-IgY-Hp was inhibited by low temperature, H<sub>2</sub>O<sub>2</sub> or acetic acid. It was concluded that internalization of FITC-IgY-Hp into yeast cell is a vital phenomenon and follows the endocytosis pathway. Furthermore, it was proposed that FITC-IgY-Hp internalization could be recruited for localization and identification of <italic>H. pylori</italic> inside the vacuole of <italic>Candida</italic> yeast.</p>