is indicated. Although both vectors function to complement mutations of the 
CFTR gene in epithelial cells derived from individuals with CF in an 
appropriate fashion, direct comparisons of the two vectors with Northern, 
immunohistochemistry , immunoprecipitation followed by phosphorylation with 
kinase and functional assays (ability to secrete Cl - in response to eleva- 
tions of cAMP) demonstrated that AdCFTR consistently yielded more expres- 
sion/function per pfu. Based on this analysis, a decision was made to use 
AdCFTR for the clinical protocol. 
The following sections provide an overview of the structure of the adeno- 
virus, the fabrication and production of the recombinant adenoviruses 
AdCFTR and AvlCFl, the structure of AdCFTR and AvlCFl, formulation of the 
recombinant vector for the clinical protocol, and the various quality 
control parameters to assess the recombinant virus to be used in the clini- 
cal protocol. 
2 . 1 Overview of the Adenovirus 
The adenovirus is comprised of linear, double stranded DNA complexed with 
core proteins and surrounded with capsid proteins. The intact virion has 
icosahedral symmetry (20 plane faces, 12 vertices), a molecular mass of 
175-185 x 10 6 Da, and a diameter of 88 nm (see Ginsberg, 1984; Horwitz, 
1990a; Berkner, 1988 for an overview of adenoviruses; Stewart et al., 1991 
for the 3-dimensional structure). The 36 kb of double stranded DNA compris- 
es 11.6-13.5% (by weight) of the virus. The remainder is protein, except 
for approximately 1% carbohydrate. There is no lipid. The virion sediments 
at 31-32S and has a buoyant density in CsCl of 1.33 - 1.35 g/ml . 
There are 47 distinct serotypes of adenoviruses and several additional 
viruses being considered for classification (Hierholzer, 1992). The clini- 
cal illnesses associated with adenovirus infection differ among groups of 
serotypes. The illnesses are usually mild but on rare occasions can be life 
threatening. The common illnesses include acute febrile pharyngitis, 
kerato-conjunctivitis , and gastroenteritis. Less commonly, adenovirus 
infection is associated with bronchitis, pneumonia, a pertussis-like syn- 
drome, acute hemorrhagic cystitis, and hepatitis. Adenovirus is widespread 
in the general population, with evidence of anti -adenovirus antibodies in 
most adults. For example, in 1954 in Washington, D.C., >95% of individuals 
surveyed had serologic evidence of prior adenovirus infection by ages 16-34 
years (Straus, 1984). 
The AdCFTR and AvlCFl vectors to be used in this protocol are based on 
adenovirus type 5, a common serotype belonging to subgroup C, a subgroup 
that includes serotypes 1, 2, 5, and 6 and is variably associated with 
malaise, fever, chills, myalgia, headache, rhinorrhea, nasal congestion, 
sneezing, anorexia, conjunctivitis and pharyngitis (Horwitz, 1990a; Straus, 
1984). A 10 year study in Washington, D.C. revealed two annual peaks in 
adenovirus -associated respiratory illness, July and December (Straus, 
1984) . Following respiratory adenovirus infection, shedding is observed 
from the respiratory tract, but fecal shedding continues for a longer 
period (Fox et al., 1969). Adenovirus -associated respiratory disease can be 
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