Live attenuated virus vaccines for la crosse virus and other bunyaviridae

Abstract

The invention relates to vaccine compositions including CEV serogroup immunogens, attenuated and inactivated viruses of the CEV serogroup and chimeric Bunyaviridae. Also disclosed are methods of treating or preventing CEV serogroup infection in a mammalian host, methods of producing a subunit vaccine composition or an immunogenic composition, isolated polynucleotides comprising a nucleotide sequence encoding a CEV serogroup immunogen, methods for detecting La Crosse virus (LACV) infection in a biological sample and infectious chimeric Bunyaviridae.

We claim: 
     
         1 . A method of inducing an immune response against a California encephalitis virus (CEV) infection in a mammal, comprising administering to the mammal a therapeutically effective dose of an immunogenic composition comprising a nucleic acid encoding a CEV serogroup immunogen or an immunogenic composition comprising a polypeptide encoded by the nucleic acid, wherein the immunogen comprises a mutation at amino acid 148 of G N . 
     
     
         2 . The method of  claim 1 , wherein the mutated amino acid at position 148 of G N  is Alanine. 
     
     
         3 . The method of  claim 1 , wherein amino acid 148 of G N  is deleted. 
     
     
         4 . The method of  claim 1 , wherein the mutated amino acid at the position 148 of G N  is any amino acid other than Threonine. 
     
     
         5 . The method of  claim 1 , wherein the nucleic acid is codon-optimized for expression in humans. 
     
     
         6 . The method of  claim 1 , wherein amino acid position 148 of G N  corresponds to amino acid position 33 of SEQ ID NO: 33. 
     
     
         7 . A method for detecting La Crosse virus (LACV) infection in a biological sample, the method comprising:
 (a) isolating nucleic acid from a biological sample suspected of containing LACV RNA, wherein if LACV is present, said nucleic acid comprises a target sequence;   (b) reacting the LACV nucleic acid with a detectably labeled probe sufficiently complementary to and capable of selectively hybridizing with the target sequence, wherein said reacting is done under conditions that provide for the formation of a probe/target sequence complex; and   (c) detecting the presence of label as an indication of the presence of the target sequence, wherein the probe is selected from the group consisting of an oligonucleotide comprising the nucleotide substitution A503G resulting in an amino acid change at position 148 in G N , and reverse complement thereof.   
     
     
         8 . A method for detecting La Crosse virus (LACV) infection in a biological sample, the method comprising:
 (a) isolating nucleic acid from a biological sample suspected of containing LACV RNA, wherein if LACV is present, said nucleic acid comprises a target sequence;   (b) amplifying the nucleic acid using at least two primers wherein each of the primers is not more than about 50 nucleotides in length and each of the primers is sufficiently complementary to a portion of the sense and antisense strands, respectively, of LACV isolated nucleic acid, if present, to hybridize therewith, and further wherein at least one of the primers is capable of selectively hybridizing to the target sequence; and   (c) detecting the presence of the amplified nucleic acid as an indication of the presence or absence of LACV in the sample, wherein one of the primers is selected from the group consisting of an oligonucleotide comprising the nucleotide substitution A503G resulting in an amino acid change at position 148 in G N , and reverse complement thereof.   
     
     
         9 . The method for detecting La Crosse virus (LACV) infection in a biological sample according to  claim 8 , wherein at least one of the primers is capable of selectively hybridizing to the target sequence.