Abstract
INTRODUCTION: Yolkin is an egg yolk-derived protein with well-established immunoregulatory activities. In this study its potential restorative properties in cyclophosphamide (CP)-immunocompromised mice were evaluated. MATERIAL AND METHODS: Mice were treated with a sublethal dose of CP, followed by an access to yolkin contained in drinking water. The mice were immunised with oxazolone (OXA) for contact sensitivity (CS) and with ovalbumin (OVA) for the antibody specific response after 15 or 26 days of treatment with yolkin, respectively. The lymphoid organs were isolated for determination of immune cell numbers and their phenotypes. RESULTS: A significant suppression of CS following CP treatment and a restoration of this response by yolkin were found. However, no effects of CP and yolkin on the antibody response were registered. In the case of CS a significant loss of T cell numbers in splenocytes was noted. The restoration of CS correlated with reversal of CD3+, CD4+ and CD8+ T cell loss to 88%, 89% and 76.6% of the values observed in the control mice. A significant depletion of the B cells, and all bone marrow cells after CP treatment, was completely restored after 26 day treatment with yolkin. CONCLUSION: The presented results add new information to the already described immunoregulatory properties of the protein and indicate a potential of oral yolkin in restoration of cellular immune response in immunocompromised individuals.