Natural killer cell activity irreversibly decreases after Cryptosporidium gastroenteritis in neonatal mice

This study aimed to investigate prolonged effects of cryptosporidiosis on innate immunity and growth in neonatal C3HA mice. The disease was challenged by Cryptosporidium parvum oocyst inoculation into 7‐days old animals. The mice whose intestine smears contained 3‐5 or 6 and more oocysts per microscopic field at the day 5 after infection were considered as mildly or severely infected, correspondingly. To determine natural killer cell (NK) activity, we applied 3H‐uridine cytotoxic assay to the animals at 5‐68 days after infection using K562 cells as targets. At severe infection, there was a statistically significant 1.5‐2.0 fold decline of body mass, spleen mass and spleen cellularity that persisted in animals of all ages. Accordingly, NK cytotoxicity showed even more drastic drop reaching 2.7‐3.0 folds that was statistically significant in all animals. At mild infection, the discovered effects were less pronounced and reached significance only in some age groups. Thus, our study provides evidence that NK cells show long‐term cytotoxic activity decrease following Cryptosporidium infection in neonatal mice, particularly in severe disease. This article is protected by copyright. All rights reserved.
Source: Parasite Immunology - Category: Parasitology Authors: Tags: Original Paper Source Type: research