Tobacco Documents Online

0 CTR 0028/CTR 1011 Progress Report 1978 1" nRSTRACT H T®0123002 The coar.°)1 n(- 1 i• r rn)'C for ...'!t r;:.^t nr' '113 :1^l Grant No. 1011 for the period January 1978 - December, 1978 is as follows: a) Using eithcr fresh or frozcn spleen tiss>>c, or uLing different cell types to gtow the X-tropic viruses, the variati or in X-tropic viras expression between the ']ZB and 129 strains of mice is regulated as a single autosomal 'dominant-likc' ge ne. J b) in croe,ses between the NZB ani SWR strains, X-tropic virus expression segregates as a single autosomal 'dominant- like' gene. c) Seven backcross generation s have been comrleted toward the generation of the congenic line. By the 10th 5eneration we will have a 129 strain that carries the gene from the tiZB mouse that regulates expression of X-tropic viruses. After 3 or 4 brother-sister matings of virus positive mice, a con- genic strain will be derived. d) Ten different isozymes have been analysed electrophor- etically in six different strains of mice. Only three c3ifferences exis' between the NZB and 129 strains and so mapping of the locus ,controllina for X-tropic virus expresslon will await c9etermin ation on more single locus differences. e) A sensitive and rapid radioimmunoassay for the viral p30 protein has been developed. The viral antigen can be detected in every one of the spleen tissue homogenates from the >\7.R mice and is undetected in spleen tissue from 129 mice. In bacl:cro ss and r2 progeny, pre]indnary data show that p30 expression is gcnet- ically linked to complete infectious X••tropic virus expression. f) No correlation between infectious X-tropic virus ex- pression and susceptibility to 3-mcthylcholanthrcne-inc9uced sub- cutaneous fibrosarcomas was observed. Studies are still on test to determine whether chemically-indur_ed lung cancers' or leul:emias are affected by the virai status of the host. g) The serum factor that neutralizes specifically the mou:.e X-tropic virus was found to be associated with mouse lipo- proteins and was not an immunoglobulin. This factor vas found in the very lox. density 1ipoP•-otein and ch}•1omicron fraction and in the high de:r.ity lipoprotein iractions. It was associritie,.9 with an apolipoprctcin and varied with diet. Itt role in con trol of normal cell development is being studied. h) The NZ11 mtce in our laborai.ory have failed to expres s any evidence of iir,riuno Cc>:n,r1cY glomerulo nephritis or anti- erythrocytic antibody. Soaie preliminary evidence was observed for anti-nuc]c3r antibc+iy that is prcfcrentially o')serveO in NZB micc.

! NT10123003 s