Virulence of La Crosse virus is under polygenic control.
نویسندگان
چکیده
To identify which RNA segments of the California serogroup bunyaviruses determine virulence, we prepared reassortant viruses by coinfecting BHK-21 cells with two wild-type parents, La Crosse/original and Tahyna/181-57 viruses, which differed about 30,000-fold in virulence. The progeny clones were screened by polyacrylamide gel electrophoresis to ascertain the phenotype of the M and S RNA segments, and RNA-RNA hybridization was used to determine the genotype of selected clones. Two or three clones of each of the six possible reassortant genotypes were characterized quantitatively for neuroinvasiveness by determining the PFU/50% lethal dose (LD50) ratio after subcutaneous injection into suckling mice. The reassortants fell into two groups. (i) Six of seven reassortants with a La Crosse M RNA segment were as virulent as the parent La Crosse virus (about 1 PFU/LD50); the one exception was strikingly different (about 1,000 PFU/LD50) and probably represents a spontaneous mutant. (ii) The seven reassortants with a Tahyna M RNA segment were about 10-fold more virulent than the parent Tahyna virus (median 1,600 PFU/LD50 for reassortants and 16,000 PFU/LD50 for Tahyna virus). A comparative pathogenesis study in suckling mice of one reassortant virus and the parent Tahyna virus confirmed the greater neuroinvasiveness of the reassortant virus. From these data it was concluded that the M RNA segment was the major determinant of virulence, but that the other two gene segments could modulate the virulence of a nonneuroinvasive California serogroup virus.
منابع مشابه
Recently introduced Aedes albopictus in the United States: potential vector of La Crosse virus (Bunyaviridae: California serogroup).
A population of Aedes albopictus collected in 1986 in Harris County, Texas, was evaluated for its vector competence with 4 California serogroup viruses (Jamestown Canyon, Keystone, La Crosse and trivittatus). Rates of midgut infection, dissemination of virus beyond the midgut and oral transmission to suckling mice were markedly different for the 4 viruses in a pattern representative of the anti...
متن کاملMonoclonal antibodies against La Crosse virus.
Monoclonal antibodies have been used to show that an epitope is present on the G1 glycoprotein of prototype La Crosse virus that is absent or significantly altered on several isolates of La Crosse virus made in New York State, U.S.A. The portion of the G1 protein where this epitope is located plays a role in both virus neutralization and haemagglutination. Additional experiments revealed that u...
متن کاملLa Crosse Virus in Aedes albopictus Mosquitoes, Texas, USA, 2009
We report the arthropod-borne pediatric encephalitic agent La Crosse virus in Aedes albopictus mosquitoes collected in Dallas County, Texas, USA, in August 2009. The presence of this virus in an invasive vector species within a region that lies outside the virus's historically recognized geographic range is of public health concern.
متن کاملIntroduction of Aedes albopictus into a La Crosse virus--enzootic site in Illinois.
In late summer and fall 1997, Aedes albopictus mosquitoes were found in Peoria, Illinois, a long recognized focus of La Crosse virus transmission. Larvae were found in tires and other artificial containers, biting adults were recovered, and eggs were collected in oviposition traps within a 25-ha area. One chipmunk trapped < 0.25 km from the infested area tested positive for neutralizing antibod...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of virology
دوره 59 1 شماره
صفحات -
تاریخ انتشار 1986