Food Sci. Biotechnol. 22(6): 1699-1705 (2013) DOI 10.1007/s10068-013-0269-4 In vitro Cytoprotective Effect of Infant Milk Formula Fortified with Human Rotavirus-specific Hyperimmune Yolk Immunoglobulins (IgY) Shofiqur Rahman, Kouji Umeda, Faustino C. Icatlo, Jr., Ki Woong Lee, Sung Han Kim, Hyuk Joon Choi, Bok-Kyung Han, Young-Seo Park, and Nguyen Van Sa Received: 7 February 2013 / Revised: 9 April 2013 / Accepted: 17 April 2013 / Published Online: 31 December 2013 © KoSFoST and Springer 2013 Abstract Infant formula supplemented with hyperimmune immunoglobulin Y (IgY) against human rotavirus (HRV) was evaluated in vitro against HRV reassortant clinical strains ATCC VR 2273 and ATCC VR 2274. Specific anti- human rotavirus antibody powder (Rotamix IgY) was prepared. The effectiveness of Rotamix IgY alone and as a pre-mixed solution with infant formula was evaluated for neutralizing rotavirus infectivity in MA104 cells. The test infant formula cross-reacted strongly against different human rotavirus strains with titers of 80-320 using a 50% fluorescent focus (FF) inhibition test. Both rotamix IgY alone and in a pre-mixed solution with infant formula showed multi-serotypic cross neutralization activities against the major rotavirus global serotypes G1, G2, G3, and G4 alone and with other human and animal- strains in vitro. Cell-rotavirus adhesion and cell damage arising from rotavirus infection were significantly inhibited in a dose dependent manner, compared to control IgY supplemented infant formula. Keywords: rotavirus, immunoglobulin Y, infant formula Introduction Among viral, bacterial, and parasitic agents causing acute infectious gastroenteritis, rotavirus is the leading single etiologic agent of severe diarrhea among infants and young children worldwide during the first 5 years of life (1). It is estimated to be responsible for over 500,000 deaths in infants and young children, mostly in developing countries, each year. This represents approximately 5% of all deaths (2). From different studies, serotype G1 of rotavirus has emerged as the most common global serotype in circulation (3). Epidemics of serotypes G2, G3, and G4 have also been detected from time to time in many countries. Therefore, any proposed control measure must take into account adequate protection against the above four epidemiologically significant HRV serotypes. Conventional treatment is largely symptomatic and involves fluid and electrolyte replacement and maintenance of nutrition. No specific, effective, and affordable therapy is currently available. The use of current vaccine regimens has been in question due to variable degrees of efficacy (4) and limitations on use for children aged less than 3 months (5). Passive immunotherapy could have advantages over vaccines due to: 1) quicker immune response, 2) broader application areas (at any age level ranging from mature to a deficient or immature immune system, like infants), and 3) lower production costs. Passive oral immunotherapy using specific chicken antibodies (IgY) has been applied with mixed success against infectious diseases of viral, bacterial, and fungal origin in both humans and animals (6-8). Peroral administration with IgY is an attractive approach because IgY does not activate the mammalian complement or interact with mammalian Fc receptors that could mediate Shofiqur Rahman (), Kouji Umeda, Faustino C. Icatlo, Jr., Nguyen Van Sa Immunology Research Institute in Gifu, EW Nutrition Japan K.K., Gifu 501-1101, Japan Tel: +81-58-235-7303; Fax: +81-58-235-7505 E-mail: rahman@ew-nutrition.co.jp Ki Woong Lee, Sung Han Kim Namyang Dairy, Sejong 339-914, Korea Hyuk Joon Choi, Bok-Kyung Han BK bio Co., Ltd., Seongnam 462-819, Korea Young-Seo Park Department of Food Science and Biotechnology, Gachon University, Seongnam 461-701, Korea RESEARCH ARTICLE