Determination of the duration of a primary immune response and the ID50 of ALA rabbit rotavirus in rabbits.
The rabbit model of rotavirus infection has been used to examine the immune response to rotavirus infection and to evaluate strategies for rotavirus vaccine development. To determine the 50% infectious does (ID50) of tissue culture adapted ALA virus, rabbit were orally inoculated with 10(1)-10(3) PFU of ALA rotavirus. The ID50 of ALA virus was determined to be 1.7 x 10(2) PFU. The immune response induced in rabbits infected at low virus doses (10(2)-10(3) PFU) was of similar magnitude to the immune responses induced with a high dose (10(6) PFU) inoculum, indicating that the immune response to ALA rotavirus in rabbits is not dose dependent. To determine if a single rotavirus inoculation would induce a long lasting immune response, four rabbits were inoculated once with ALA virus (3.5 x 10(5) PFU) and their serologic and mucosal antirotavirus titers were monitored at intervals for 1.5-2 years. The infected rabbits maintained serologic and mucosal rotavirus antibody titers until the final time point more than 700 days post inoculation. These data are important because they indicate that the antigenic load achieved following a single oral inoculation is sufficient to achieve long lasting immunity, the goal of any potential vaccine.
Veterans Affairs Medical Center, Baylor College of Medicine, Houston, Texas, USA.
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Conner
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Graham
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D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology; D018928:Immunity, Mucosal; D011817:Rabbits; D012401:Rotavirus / Q000276:immunology* / Q000472:pathogenicity*; D012400:Rotavirus Infections / Q000276:immunology / Q000821:virology; D013997:Time Factors
D000914:Antibodies, Viral