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M Janowski

Publications and source records attributed to M Janowski.

10 recordsLinked to original sources
PubMed1979

Radioimmunoassay determination of two main cross-reacting viral antigens during radiation and Rauscher induced leukemias.

The two main proteins p 30 and gp 70 from the Rauscher leukemia virus (RLV) have been isolated, labeled with 125I and used in radioimmune competition assays to estimate the amount of cross-reacting antigens produced during the evolution of various leukemias. The Rauscher leukemia in Balb/c mice, the radiation induced leukemia (RadLV) in C57Bl mice and two types derived therefrom by serial passages in mice (RadLV-RS) and in rats (RadLV-rat) were studied. Whereas the p 30 from RLV or RadLV (rat) viruses showed complete identity, the cross-reaction of their gp 70 proteins wasonly partial. The main findings in the tissues were the following: 1. The concentration of p 30 and gp 70 antigens increased much more during the RadLV-rat leukemia than in irradiated or RadLV (RS) treated mice. 2. In the serum, the ratio p 30/gp 70 was in general higher than one in the Rauscher leukemic mice and less than one in all types of RadLV leukemias. 3. In the spleen, RLV and RadLV (RS) infected mice had higher levels of p 30 than of gp 70. The reverse occurred in irradiated mice and in leukemic rats. Finally, the catabolic degradation of labeled RLV gp 70 was similar in normal and leukemic mice.

Animals↗
PubMed1978

[A and C particles in mouse embryos].

Electron microscopic examination of embryos of the BALB/c and AKR strains of mice from the 1-cell stage to 14 days of age revealed 2 types of intracisternal A particles, one type of C particle budding into the extracellular space and an endoplasmic reticulum-association "dense-cored veiscle". The occurrence of the particles showed a marked dependence on the developmental stage of the embryo. A small percentage of 1 blastomere embryos in both strains showed the presence of a small number of A particles. Embryos of 1 to 16 blastomeres of the AKR strain with A particles were on average more frequent than in the BALB/c strain. The percentage of 7 and 14 day embryos with C particles was much greater in AKR than in Balb/c mice.

Animals↗
PubMed1978

Characterization by molecular hybridization of two viral populations derived from a radiation leukemia virus.

Two leukemogenic viral populations were derived from a radiation leukemia virus of the C57BL mouse. One (FB), in which only B-tropic virus could be detected, was obtained in vivo by serial passage of cell-free extract in newborn rats. The second (3C), a complex containing at least B-tropic and xenotropic viruses, was produced in vitro by a permanent cell line (13-3C) established from the spleen of a virus-infected C57BL mouse. In molecular hybridization experiments, the 70S RNA of Gross leukemia virus hybridized 96 and 78% of FB and 3C radioactive complementary DNA's, respectively, with a relatively high thermal stability of the duplexes formed. In contrast, the 70S RNA of Rauscher leukemia virus hybridized 23 and 20% of the FB and 3C DNA probes, respectively, with a low thermal stability. The rat-grown FB virions exhibited 50% genome homology with the viruses produced in vitro on the 13-3C cells. Finally, hybridizing the FB and 3C probes with normal or leukemic mouse spleen DNA's resulted in 89 to 100% homology. The rat-grown virions did not appear to contain detectable rat cellular DNA sequences, while about 20 complete copies of their nucleotide sequences were detected in covalent linkage with FB-infected rat spleen DNA. These findings strongly support the endogenous murine origin of the investigated virions.

AKR murine leukemia virus↗