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As a business owner, you should be asking yourself several questions: What resources you have in terms of people and money, how can you grow to where you want to [...]

A survey by the National Association of Retail Marketing Services, an association that represents the professional merchandising and marketing services industry, reports that as a national average, companies lose 10 [...]

The mission of the IFA Women's Franchise Committee is to 'empower leaders in franchising by promoting women's participation in the industry and providing international networking opportunities for the exchange of [...]

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It's a typical sunny Friday afternoon in Southern California and the shipment of new training manuals has just arrived for the franchisee training class on Monday morning. As the first [...]

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The all-in-one solution is 'out there.' The key to true data management is finding the right partner, says American Leak Detection. Franchise data management, does the true concept really exist? [...]

Various studies have reported that, on average, well over 50 percent of the technology projects that are started fail. What's more, many of them are fantastic concepts. Why then are [...]

Q: What do you think is the single most important aspect of social media to the franchise industry? To your company? Ensuring brands elevate social media to a separate line [...]

The replication of the diabetogenic D (EMC-D) and nondiabetogenic B (EMC-B) variants of encephalomyocarditis virus in various tissues of the murine host was determined. Pancreatic insulin levels were also measured. EMC-D replicated in the spleen, pancreas, heart, lung, and intestines, while EMC-B was limited to the spleen and pancreas. EMC-B interfered with the replication of EMC-D in each of the tissues examined. Insulin levels were initially increased by both viruses. By 4 days postinfection, insulin levels were either normal or undetectable in (EMC-D)-infected animals, but were dramatically elevated in those infected with EMC-B.

To assess the separate contributions of host T cells and the physical state of the antigen in the development of effective. Salmonellaresistance, glutaraldehyde-treated and untreated protein- and ribonucleic acid-rich extracts (E-RNA extracts) of virulent Salmonella typhimuriumSR-11 or attenuated S. typhimuriumRIA were used to immunize Salmonella-resistant Salmonella-susceptible strains of mice for the purpose of determining whether antigen-specific T-cell or B-cell responses were formed and, if so, which responses predominated. The resistance imparted to each mouse strain after vaccination with S. typhimuriumRIA was used as the standard for comparison. The inbred mouse strains C57BL/6 and DBA/2 and their F1hybrid (strain BDF1), outbred ICR Swiss mice, and endotoxin-resistant C3H/HeJ mice were examined for the capacity to develop resistance to lethal Salmonellainfections, as well as the ability to generate antigen-reactive T cells. Only the BDF1, C3H/HeJ, and ICR Swiss mice were able to develop resistance to challenge infections mediated by the virulent SR-11 strain of S. typhimuriumafter vaccination with the living, attenuated RIA strain of S. typhimuriumor immunization with E-RNA extracts. We developed an assay to identify the antigen-reactive rosette-forming lymphocytes present in lymph nodes and spleens of immunized mice. Levels of 0.2% or higher of theta antigen-bearing, antigen-reactive rosette-forming cells were found in the lymph nodes or spleens or both of only the BDF1, C3H/HeJ, and ICR Swiss mice (i.e., in the “Salmonellaresponder” strains). Mouse strains C57BL/6 and DBA/2, which failed to develop resistance to lethal infections after immunization with the S. typhimuriumRIA vaccine or with the E-RNA extracts, lacked effective numbers of antitheta antigen-sensitive rosette-forming cells. Modification of the effective E-RNA extracts by polymerization with glutaraldehyde resulted in a marked diminution in their abilities to induce resistance to salmonellosis in the two responder mouse strains tested (BDF1and ICR Swiss), even though detectable levels of antibody were induced.

Cytophilic macroglobulin was eluted (by heating at 56 C for 60 min) from lymphoid cells of mice immunized with subfractions of virulent Salmonella typhimuriumSR-11 or vaccinated with an attenuated strain of S. typhimurium(RIA). No such macroglobulin was present on comparable cell populations from normal or adjuvant-injected mice. Cytophilic macroglobulin was also present in the sera of immunized mice. In mice immunized with RNA and protein-containing subfractions extracted from lysates of S. typhimuriumSR-11, the cytophilic macroglobulin was present by 14 days after immunization, whereas it was present by 10 days in mice injected with living attenuated S. typhimuriumRIA. This macroglobulin reacts specifically with protein-rich components present in the immunogenic subfractions of the whole bacterial cells and has been demonstrated to facilitate phagocytic uptake of virulent S. typhimuriumSR-11. Moreover, a similar protein material was present in broth culture media in which the salmonellae were cultivated. Greater amounts were detectable in older (4 day) cultures.

Manifestations of delayed hypersensitivity (cell-mediated immunity) were found to be present in mice immunized with virulent Salmonella typhimuriumSR-11 subfractions which contained appreciable concentrations of bacterial protein and in mice immunized with the living, attenuated RIA strain of S. typhimurium.Delayed hypersensitive responses were measured by footpad sensitivity in the immunized mice and in vitro by inhibition of spleen cell migration and by increase in 3H-thymidine uptake by lymphoid cell populations when exposed to bacterial fractions rich in protein content.

Mice were injected with virulent Salmonella typhimuriumSR-11 subfractions containing varied amounts of ribonucleic acid (RNA) and protein or with living attenuated S. typhimuriumRIA. In these mice, maximal resistance to lethal infection by 1,000 or 5,000 median lethal doses of S. typhimuriumSR-11 was seen 2 to 3 weeks after immunization. The S. typhimuriumRIA vaccine and a crude ethanol-precipitated RNA fraction (E-RNA) prepared from lysates of S. typhimuriumSR-11 were the most efficient immunogens inducing protection against salmonellosis. The contribution of the components present in the E-RNA fractions to host protection against lethal salmonella infection was also examined. RNA-rich fractions (P-RNA) prepared from lysates of the virulent salmonellae contained several bands of protein when examined by disc electrophoresis. P-RNA fractions stimulated protective immunity in mice to infection with S. typhimuriumSR-11 but to a much lesser degree than did the E-RNA fractions or strain RIA vaccine. Protein-rich fractions (NP), separated from E-RNA by salt precipitation, exhibited the same number and distribution of protein bands by disc electrophoresis as did the parent E-RNA fractions. Mixtures of either bovine liver soluble RNA or various synthetic polynucleotides and NP were examined, as was NP fraction alone, for the ability to confer protection in mice to challenge infections by the virulent strain of salmonella. Polyadenylic-uridylic acid plus NP conferred significant protective immunity to challenge infections in mice immunized with this mixture, being nearly as effective an immunogen as were the E-RNA fractions of S. typhimuriumSR-11 or the attenuated S. typhimuriumRIA.

Mice immunized with purified whole-cell ribonucleic acid (RNA), RNA from the bacterial “particulate” fraction, and ribosome-associated RNA obtained from Salmonella typhimuriumwere found to be resistant to subsequent challenge infection with virulent salmonellae. Chemically, the immunogenic nucleic acid fractions contained from 1 to 3% “contaminant” material defined (based on the mean of 19 different preparations) as protein (0.24%), deoxyribonucleic acid (0.43%), methyl pentose (0.64%), hexose (1.58%), and undefined carbohydrate (0.76%). Heptoses and lipoidal material were not detectable in any of the immunogenic preparations examined. Physically, the nucleic acid preparations, after analytical ultracentrifugation, exhibited three boundaries similar to those reported elsewhere in comparable systems: 4 to 5S, 16S, and 23S. An evaluation of the immunity induced by the ribosome-associated RNA established that the immune response was (i) comparable to that induced 15 days postimmunization with live salmonellae and by ribosomal vaccines, but greater at 30 days postimmunization than that in mice immunized with attenuated salmonellae; (ii) dependent on the quantity of immunogen administered; (iii) dependent on the size of the infective inocula; (iv) inhibited at 15 but not at 30 days postimmunization when the immunogenic nucleic acid preparations were incorporated into Freund's incomplete adjuvant, (v) reduced or lost by dialysis in relatively high or low immunizing doses, respectively; and (vi) unaffected by enzymatic treatment of the preparations with trypsin, deoxyribonuclease, Pronase plus pancreatic ribonuclease, or pancreatic ribonuclease alone. The possible mode of action of ribosome-associated RNA in inducing an immune response to subsequent challenge infection with the homologous organism is discussed.

Ribosomal preparations obtained from Salmonella typhimuriumby differential centrifugation and sodium dodecyl sulfate (SDS) treatment of the bacillary lysate were found to be immunogenic in F1hybrid (C3H/HeJ × DBA/2J) and albino Swiss mice, as determined by progressive host survival. The immunity obtained was independent of the need for adjuvant and dependent on the dosage of immunogen given. Immunizations with the ribosomal preparations induced an immune response comparable to that obtained by vaccination with living organisms and significantly greater than that obtained by immunization with heat-killed salmonellae, purified lipopolysaccharide, or crude and SDS-treated endotoxin preparations. No effect on the immunogenicity of the ribosomal fraction was observed by enzymatic treatment with trypsin, Pronase, deoxyribonuclease, and pancreatic ribonuclease. Linear sucrose density gradient resolution of the preparations showed that the immunogenicity of the ribosomal fraction was not unique to any one of its subcomponents. Ethyl alcohol-precipitated, crude ribonucleic acid preparations obtained from the ribosomal and sucrose density-resolved ribosomal preparations were found to induce an immune response comparable to that obtained by immunization with the entire ribosomal fraction. Dialysis in doubly distilled demineralized water slightly reduced the immunogenicity of the preparation; however, comparable dialysis in 10−4mMgCl2-phosphate buffer did not. Chemical assays of the preparations found to be immunogenic were performed.