William H. Murphy

Age-dependent paralytic viral infection in C58 mice: possible implications in human neurologic disease.

Publisher Summary This chapter analyzes the specific ways that aging, viral infection, genetic factors, and immune deficiency act together to predispose mice to paralytic disease using an age-dependent motor neuron disease in C58 mice as an experimental model. Lactic dehydrogenase virus (LDV) is widespread in both domestic and wild mice and causes life-long infection. Immune complexes typically are found in the plasma of infected mice. LDV does not cause significant pathologic changes in the tissues of infected mice under ordinary circumstances. The properties of LDV are summarized in the chapter. LDV derived from line Ib transplantable leukemia causes a fatal inflammatory motor neuron disease when inoculated into C58 mice that are 9 or more month of age, and in younger C58 mice, providing that they are immunosuppressed first by X-irradiation or drugs. LDV strains differ markedly in their neuropathogenicity ranging from those that are highly paralytic to those that cause inapparent infection.

Etiologic role of lactic dehydrogenase virus infection in an age-dependent neuroparalytic disease in c58 mice.

Abstract Lactic dehydrogenase virus (LDV) associated with transplantable line Ib lymphocytic leukemia in C58/Wm mice, K36 lymphocytic leukemia in AKR/J mice, and the Gardner lymphosarcoma in C3H/HeJ mice elicited a fatal neuroparalytic disease when injected ip into 7- to 9-month-old X-irradiated indicator C58 mice. LDV associated with the WEHI-3B line of transplantable myelomonocytic leukemia or the Harding-Passey transplantable myeloma in BALB/c mice failed to elicit the disease. Recipients of such tumor extracts were immune to rechallenge by line Ib-associated LDV. Tumor lines free of LDV failed to elicit the disease or immunize recipient mice to line Ib LDV challenge. The Plagemann (P-LDV), Riley (R-LDV), and Notkins (N-LDV) strains of LDV were less neuropathogenic than the line Ib-derived strain (Ib-LDV). Indicator C58 mice that survived infection by the P-LDV, R-LDV, and N-LDV strains were immune to rechallenge by Ib-LDV. Antiserum prepared in young C58 mice to Ib-LDV or R-LDV protected indicator C58 mice from Ib-LDV challenge. These results show that a common viral contaminant of transplantable tumors and virus stocks that ordinarily is not pathogenic elicits a fatal neurologic disease in genetically susceptible, immunosuppressed, C58 mice.

RNA dependent DNA synthesis in cell free preparations of human leukemia cells

Abstract A cell free preparation of human leukemic cells, grown in tissue culture, incorporated H 3 -thymidine phosphate into an acid insoluble product which was rendered acid soluble by the action of DNAase but not KOH or RNAase. RNAase, if added before incubation of the reaction mixture, prevented incorporation of the isotope into the product. For maximum incorporation Mg and all four deoxyribonucleotide triphosphates must be present. The enzyme has the properties of an RNA dependent DNA polymerase.

FV-1 restriction of age-dependent paralytic lactic dehydrogenase virus infection

Abstract A genetic analysis was made of the susceptibility of inbred mice to a paralytic disease elicited by the ip injection of a neuroparalytic strain of lactic dehydrogenase virus. The frequency of disease in susceptible inbred mice was X-ray dose and age dependent. Analysis of the susceptibility of appropriate F 1 hybrids and their backcross progeny showed that susceptibility was not linked to the major histocompatibility complex but segregated with the Fv-1 linkage group. Linkage group analysis showed that resistance to paralytic infection was linked to a single gene outside the major histocompatibility complex. By determining the segregation of Gpd-1 isozyme variants among backcross progeny it was shown that inheritance of the Fv-1 b allele resulted in virtually absolute restriction of susceptibility. Genetic evidence was obtained indicating that mice that mice that had multiple copies of N-tropic C-type retroviruses in their genomes, and that were permissive for retrovirus expression ( Fv-1 n/n ), were susceptible to paralytic LDV infection. Strains that carried few copies of N-tropic C-type retroviruses in their genomes, or that inherited the Fv-1 b allele, were resistant. A significant maternal resistance effect was demonstrable in some backcross generations that appeared to be mediated by H-2 b in the major histocompatibility complex.

Urine-based diagnostic technologies

The worldwide dissemination of infectious agents has created a demand for simple diagnostic tests. Urine-based testing makes use of non-invasive collection of specimens, and there is no need for expensive facilities and equipment, or for highly trained personnel. As urine antibodies retain activity under normal conditions of transport and storage, such tests appear to have widespread application. Urine-based antibody tests have also indicated a compartmentalized antibody response to HIV-1 infection. Urine studies suggest that antibodies to the products of endogenous viral genes may be involved in the pathogenesis of chronic diseases of suspected viral etiology.

Detection of Virus-Like Particles in Germinal Centers of Normal Guinea Pigs

Summary Virus-like particles similar in uttrastructure to the C-type virus particles found in the mouse leukemias were found selectively localized in the lymphoid germinal centers of 2–6-month-old normal guinea pigs of the Hartley stock. A second type of virus-like particle with a diameter of about 70 m μ and dense central core of 30 m μ was also found in germinal centers.

Localization of C-Type Virus Particles in Lymphoid Germinal Centers of C58 Mice.∗

Summary A systematic electron microscopic study was done on bone marrow, spleen, lymph node, and thymus tissues of C58 mice which have a high incidence of spontaneous lymphocytic leukemia. The primary objective was to determine the frequency and distribution of virus particles over the lifespan of these mice. The unique finding was made that C-type virus particles were localized in germinal centers of the spleen and lymph node of young (3 to 6.5 months old) preleukemic mice. C-type particles were associated with the lacy network of reticular cell dendritic processes in germinal centers. Virus particles were found infrequently in other areas of the spleen or lymph node, thymus and bone marrow of preleukemic mice. Alterations were observed in the cytoarchitecture of the reticular cell networks that contained many particles. The possible importance of the occurrence of C-type particles in lymphoid germinal centers was discussed in terms of the pathogenesis of spontaneous leukemia.

RT-PCR amplicons in the plasma of multiple myeloma patients clinical: Relevance and molecular pathology

The occurrence of RNA (RT-PCR amplicons) in the plasma of 70 patients was quantified: 65 patients with multiple myeloma (MM), 3 with Waldenstroms macroglobulinemia (WM), 2 with monoclonal gammopathy of undetermined significance (MGUS), and 50 from healthy controls. A 713nt amplicon occurred in 16/18 MM patients in relapse, 5/8 untreated patients, 2,3 WM patients and 1,2 MGUS plasmas. None of the initial specimens from 37 patients in remission nor the 50 healthy controls was positive. Homology between 4 sequenced 713nt amplicons was > 99.7% and matched (99.6%) a 704nt sequence of the flanking region of the peroxisome proliferator activator receptor gene, located on chromosome 22q11.2. A 255mer within the 713nt amplicon had a 90.2% homology with an AluSc consensus sequence. The occurrence of RNA amplicons seemed to serve as accurate surrogate markers for active disease in MM that provide new insights to the molecular pathogenesis of the disease.The occurrence of RNA (RT-PCR amplicons) in the plasma of 70 patients was quantified: 65 patients with multiple myeloma (MM), 3 with Waldenstroms macroglobulinemia (WM), 2 with monoclonal gammopathy of undetermined significance (MGUS), and 50 from healthy controls. A 713nt amplicon occurred in 16/18 MM patients in relapse, 5/8 untreated patients, 2/3 WM patients and 1/2 MGUS plasmas. None of the initial specimens from 37 patients in remission nor the 50 healthy controls was positive. Homology between 4 sequenced 713nt amplicons was >99.7% and matched (99.6%) a 704nt sequence of the flanking region of the peroxisome proliferator activator receptor gene, located on chromosome 22q11.2. A 255mer within the 713nt amplicon had a 90.2% homology with an AluSc consensus sequence. The occurrence of RNA amplicons seemed to serve as accurate surrogate markers for active disease in MM that provide new insights to the molecular pathogenesis of the disease.

Characterization of transplantable myelomonocytic leukemia wehi-3b in syngeneic balb/c mice.

Summary Three transplantable sublines of WEHI-3B myelomonocytic leukemia in BALB/c mice were developed by splenic (SP), intraperitoneal (IP) and subcutaneous (SQ) passage. All three sublines then were compared for stability on passage, lethality for mice, and major hematologic and histopathologic effects. The time in days until death was a linear function of the log10 dose of viable cells injected for each cell line. Evidence was provided that a single cell of the IP line was lethal to mice and that death from all three cell lines approximated single cell kill. All three sublines were stable after adaptation by serial passage. Detailed hematologic and histopathologic studies were done on mice that were inoculated iv and ip with the SP and IP sublines. Changes typical of myelomonocytic leukemia were observed except that bone marrow invasion was minimal.

Histopathology of serum-transmitted immune polioencephalomyelitis in C58 mice.

Summary A histopathologic study of serumtransmitted immune polioencephalomyelitis in C58 mice showed that the inflammatory nature of the CNS lesions in the serumtransmitted disease did not differ significantly from the disease actively induced by inactivated syngeneic malignant lymphocytes. The histopathology was characterized by perivascular lymphocytic infiltrates in the gray matter of the spinal cord and brain stem with accompanying microglial proliferation and neuronal destruction. Demyelination, inclusion body formation, astrocyte proliferation, and cerebral and cerebellar involvement were absent. Evidence was summarized indicating that the active serum component was not an immunoglobulin but probably a processed antigen or a lymphokine. The disease appears to result from an age-dependent autoimmune response to theta or theta-like antigens common to CNS tissues and lymphoid cells.