Showing papers by "Hilary Koprowski published in 1965"
TL;DR: In the present investigation, mycoplasmas were isolated from broth cultures seeded with three bone marrow samples obtained on the same day from one of three children suffering from acute lymphoblastic leukaemia.
Abstract: THERE are no reports of the direct isolation of myco-plasmas from human leukaemic blood or blood-forming organs, although the direct isolation of mycoplasmas from the blood of a few septic patients has been claimed1–4. In the present investigation, mycoplasmas were isolated from broth cultures seeded with three bone marrow samples obtained on the same day from one of three children suffering from acute lymphoblastic leukaemia (Table 1).
71 citations
TL;DR: It was found that these strains were much more antigenic than the same strains of virus propagated in embryonated avian egg before adaptation to tissue culture, and the use of this tissue culture vaccine in man should be contemplated.
Abstract: SummaryThe antigenicity of 2 strains of rabies virus (Flury HEP and Pitman-Moore) propagated in a Human Diploid Cell Strain and used as live and inactivated vaccine was studied in Rhesus monkeys. It was found that these strains were much more antigenic than the same strains of virus propagated in embryonated avian egg before adaptation to tissue culture. The use of this tissue culture vaccine in man should be contemplated.
42 citations
26 citations
TL;DR: With the exception of rabies-infected dogkidney cultures and one series of rabbit-endothelium cultures, all of the other cell cultures chronically infected with six different strains of rabie virus eventually showed the presence of LCMLC in the fluorescent-antibody test (Table 1).
Abstract: As a routine procedure in the study of the growth of rabies virus in tissue-culture systems (Fernandes et al., Virology 21:128, 1963; Wiktor et al., J. Immunol. 93:353, 1964), newborn mice were injected intracerebrally with various preparations of the tissue culture-passaged virus, and their brain tissues were removed for further study. On one occasion, adult mice injected intracerebrally with newborn mouse brain suspension of rabies virus showed signs of lymphocytic choriomeningitis (LCM) infection, as described by Armstrong and Lillie (Public Health Rept. U.S. 49:1019, 1934). The virus isolated from the mouse brain tissues was identified as LCMlike (LCMLC) in a neutralization test in mice injected with a mixture of the virus and serum obtained from rabbits immunized with guinea pig spleen infected with LCM (obtained through the kindness of Maurice Hilleman, Merck Sharp and Dohme, West Point, Pa.). As a result of this finding, all the tissue cultures maintained in the rabies virus laboratory were studied for the presence of LCM antigen by fluorescent antibodies, by use of either an indirect test against a nonlabeled human LCM convalescent serum (obtained through the kindness of J. Hotchin, New York State Department of Health, Albany, N.Y.) and labeled anti-human serum globulin, or by use of a direct test against serum obtained from guinea pigs immunized with LCM-infected guinea pig spleen (obtained through the kindness of Roger E. Wilsnak, Baltimore Biological Laboratories, Baltimore, Md.). The specificity of these tests was controlled by use of normal human sera that did not react with cell cultures infected with LCM virus. (Nonreactivity of these sera was verified as well by another laboratory.) The specificity of the guinea pig immune serum was established by Wilsnak and Rowe (J. Exptl. Med. 120:829, 1964); its lack of reactivity with uninfected cultures was confirmed in this laboratory. With the exception of rabies-infected dogkidney cultures and one series of rabbit-endothelium cultures, all of the other cell cultures chronically infected with six different strains of rabies virus eventually showed the presence of LCMLC in the fluorescent-antibody test (Table 1). In some cultures the LCMLC was detected soon after infection with rabies virus; in others, it was detected only several passages later. In strain LEP grown in human diploid cells, LCMLC was found only for a few passages. The origin of the six rabies strains was quite varied: LEP and HEP Flury were always maintained either in brains of newly hatched chicks or in chick embryo tissue (Koprowski, Bull. World Health Organ. 10:709, 1954) from the time of their isolation from a human source; the Pasteur and PM strains were always maintained in rabbit brain; and the CVS and Nishigahara strains were passaged in mouse brain. None of the cultures was exposed to other viruses than rabies, and none of the control cultures showed the presence of LCMLC even though these cultures were carried in the same laboratory and were handled by the same personnel. Properties of LCMLC. LCMLC could be isolated from some of the tissue cultures in an apparently \"pure\" form by passaging the infectious material in the presence of antirabies neutralizing serum (serum from a donkey immunized with phenol-treated sheep-brain vaccine, obtained through the kindness of K. Sikes, National Rabies Laboratories, Atlanta, Ga.). The character of the LCMLC preparations varied depending on the tissue-culture system used and the property of the rabies virus with which it was associated. For instance, the PM strain of rabies virus is pathogenic for adult mice injected intracerebrally, and the LCMLC isolated from the system also is lethal for adult mice. However, in contrast to the effect of the original PM strain, the LCMLC is noninfectious for adult guinea pigs, hamsters, and rabbits injected intracerebrally. The HEP Flury strain is pathogenic for newborn mice, but is nonlethal for adult mice in-
8 citations