Biomedical subjects
Publications and source records attributed to F Klein.
Procedures were developed to produce infectious Epstein-Barr virus in large glass fermentors with limited mechanical agitation by using an intermittent culture collection system. The system appears quite suitable for use in fermentation vessels of 50 liters or larger.
We present a pattern of fractionation of total lipids, leading to the isolation of individual glycolipids, MGDG contains as sugars, a high quantity of galactose and a low level of glucose. The study of the fatty acids distribution shows: a) a high level of saturated short chains fatty acids, b) a high level of palmitic acid (C 16:0, 68% of the total).
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(1) The phagocytosis of human IgG, IgM, and C3 by granulocytes from various rheumatoid and nonrheumatoid sera and synovial fluids (SF) was investigated by direct examination of the patient's leucocytes and indirect testing by incubation of normal donor leucocytes with various sera and SF. (2) In rheumatoid arthritis (RA) phagocytosis of IgM, IgG, and C3 was common from sera and SF. There was a strong correlation of IgM and C3 phagocytosis with the occurence of rheumatoid factor. The phagocytosed IgM is probably rheumatoid factor. In SF both the direct and indirect test method yielded equally positive results; in serum the direct test was negative throughout. (3) In systemic lupus erythematosus there was phagocytosis of IgG, IgM and C3 from serum (indirect test), IgM not being correlated with the latex-fixation test and probably of antinuclear antibody nature. Phagocytosis decreased after treatment of the disease. Sera from many other rheumatic disease frequently gave weak IgG phagocytosis, but rarely did IgM or C3. (4) IgG, and sometimes C3, was frequently taken up from IgG myeloma sera (indirect test). IgM and IgG were taken up from Waldenström's macroglobulinaemia sera, independent of IgM concentration. It is possible that an aggregation tendancy of particular paraproteins determines Ig uptake from these sera. (5) IgG was taken up from half of the studied sera of infectious diseases in the indirect test, including two cases with Hodgkin's disease as well. Three sera from patients with untreated trypanosomiasis were positive for IgG as well as for IgM. (6) Normal healthy control sera remained negative, even after prolonged preservation or frequent freezing and thawing: only among very old sera were a few positive observations recorded. Immunoglobulin phagocytosis appears to be a common phenomenon in a number of conditions. It seems probable that soluble immune complexes, or in other cases nonimmune aggregates, may cause phagocytosis.
JLS-V9 mouse bone marrow cells were readily adapted to suspension culture, chronically infected with Rauscher leukemia virus (RLV), and subsequently grown in 7.5- and 14-liter New Brunswick fermentors. The suspension-type cell system can be modified to produce virus with clearly defined properties, such as high ribonucleic acid-dependent deoxyribonucleic acid polymerase (RDDP) activity, high particle count, and high infectious particle count. Biological and biophysical properties of suspension-produced RLV were not affected by concentration and purification employing continuous-flow and rate-zonal centrifugation procedures. The RDDP assay was standardized and showed a linear incorporation of (3)H-thymidine 5'-monophosphate ((3)H-TMP) up to 30 min. Further characterization indicated that a high percentage of (3)H-TMP incorporation was due to RDDP.
An in vitro system for production, purification, and concentration of mouse mammary tumor virus is described. Monolayer cultures of C(3)H mouse mammary tumor cells propagated at 34 C in roller bottles in the presence of dexamethasone, a glucocorticoid hormone, release B-type particles which possess ribonucleic acid and a ribonucleic acid-dependent deoxyribonucleic acid polymerase. One thousandfold concentration by ultracentrifugation with subsequent gradient fractionation yielded > 7 x 10(10) particles per ml in the 1.16- to 1.18-g/ml region. Mouse mammary tumor virus produced in this system was free of detectable C-type virus.
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An investigation of malariometric indices in relation to immunoglobulin levels, rheumatoid factors, and antithyroglobulins was carried out on 78 members of the Arfak tribe near Manokwari in Western New Guinea, in the course of a WHO assessment of malaria control activities in that region. The population investigated had been exposed to a period of epidemic malaria, as indicated by the small differences in malariometric indices between consecutive age groups. Typically high spleen sizes were recorded, as found generally among Papuans in similar situations. Falciparum malaria was most prevalent, almost equal to cases of vivax and malariae malaria together. IgM levels were very high, while those of IgG, IgA and IgD were not elevated. Total serum protein was rather low. No correlation between malariometric indices, autoantibodies, and immunoglobulin levels could be found. In particular there was no correlation between IgM levels and spleen indices, such as has been found in many other surveys. It is suggested that splenomegaly may show no correlation with the IgM level in Papuan populations without previous selection.
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A model system is described for the mass propagation of Rift Valley fever (RVF) virus, utilizing large-volume fermentor units for suspension culture of tissue cells and the subsequent production of virus. Comparisons between laboratory- and fermentor-scale operations of tissue cell growth gave equivalent results. Cell viability dropped 24 to 30 hr postinfection with a subsequent virus yield between 10(8.0) and 10(9.0) mouse intracerebral median lethal doses per milliliter. Infecting volumes of tissue cell culture (20- or 40-liter working volumes) had no apparent effect on virus yields. Tissue cells grown under either oxidation-reduction potential- and pH-controlled or uncontrolled conditions showed little or no difference in their ability to produce RVF virus. We believe this tissue cell virus process to have potential application for large-scale production of vaccines for human or veterinary use or for the mass propagation of certain carcinogenic viruses for cancer research, once use of established lines for this purpose is accepted.
Filtration by means of a Diaflo ultrafilter was used to concentrate three 1,000-ml lots and one 3,000-ml lot of tissue culture-grown Rift Valley fever virus. Quantitation of both infectivity and total protein was achieved. Water treatment with continued ultrafiltration of the virus concentrate provided a final virus product approximately 99.25% free of low-molecular-weight materials originally present in the growth medium.
Procedures used to produce an established line of mammalian cells (L cell) in a New Brunswick fermentor were adapted to propagate human lymphoid cells in suspended culture. Control of pH within defined limits was more effective for regulation of cell metabolism than control of oxidation-reduction potential. An unusually high rate of agitation was required.
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