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Biomedical subjects

E Ribi

Publications and source records attributed to E Ribi.

At least 55 records · Page 3Linked to original sources

Delayed hypersensitivity and granulomatous response after immunization with protein antigens associated with a mycobacterial glycolipid and oil droplets.

A myocardial glycolipid (P3) mixed with protein antigens in oil-in-water emulsion induced lasting delayed hypersensitivity (DH) and granulomatous inflammation after intradermal injection into guinea pigs. This did not occur when P3 and bovine serum albumin (BSA) were given in Freund's incomplete adjuvant. The oil-in-water emulsions consisted of microscopic oil droplets suspended in aqueous medium. By separating oil and aqueous phases from BSA + P3 emulsion it was shown that antigen retained with oil droplets led to DH and granuloma formation. The association of antigen with oil droplets was P3 dependent and was quantitated with 125I-labeled BSA. The same phenomenon occurred with 125I-labeled rabbit gamma-globulin (RGG) + P3 emulsion. Fluorescein-conjugated RGG was observed in a particulate state within or on oil droplets in emulsion containing P3. These physical characteristics of antigen + P3 emulsion appeared to be important for immunogenicity.

Animals↗

Immunotherapy of cancer: tumor suppression and regression by cell walls of Mycobacterium phlei attached to oil droplets.

Components of mycobacterial cell wall(s) (CW) attached to oil droplets were evaluated for their ability 1) to inhibit the growth of line-10 tumor transplants in the skin of syngeneic guinea pigs when inoculated together with 10(6) tumor cells (suppression experiments) and 2) to regress established 7-day-old intradermal tumors and eradicate microscopic lymph node metastases upon injection into the tumors (regression experiments). CW and cell-wall skeleton (CWS) preparations from Mycobacterium phlei, a fast-growing saprophyte of group IV of the atypical mycobacteria, suppressed tumor growth in essentially all animals when 37.5-mug doses were administered; at a dose of 300 mug, they cured 50-60% of the animals in regression tests. The addition of 300 mug of a purified trehalose mycolate, isolated from M. tuberculosis strain Aoyama B, to 300 mug M. phlei CW or CWS preparations significantly increased their tumor regressive potency to provide cure rates to about 90%. Because M. phlei can be propagated more readily, it can be used advantageously in place of BCG to prepare stable, non-living immunologic adjuvants of defined composition and consistently high potency to meet the need for standards with minimal residual malignant disease.

Animals↗

Migration inhibitory factor and type II interferon in the circulation of mice sensitized with mycobacterial components.

Migration inhibitory factor (MIF) and type II interferon were released into the circulation after mice had been sensitized i.v. with a bacillus of Calmette and Guerin (BCG) cell-wall-in-oil vaccine and then challenged four weeks later with 50 mg old tuberculin. At least two components of BCG, protein (PPD) and lipid (P-3), have been identified which are essential for the type of sensitization in which mediators are released after appropriate challenge. The route of sensitization had a marked effect on the development of delayed footpad reactions, release of lymphokines, and resistance to infection with virulent tubercle bacilli. Sensitization by the subcutaneous route tended to induce more pronounced delayed footpad reactions, whereas the i.v. route of sensitization was associated with maximum release of mediators. A close correlation existed between the conditions of sensitization that resulted in maximum production of lymphokines (MIF and Type II interferon) and those that caused protection against aerosol challenge with a virulent strain of Mycobacterium tuberculosis.

Animals↗

Marihuana: identification of cannabinoids by centrifugal chromatography.

Components in extracts of marihuana and hashish have been identified by a chromatographic technique in which centrifugal force is used to accelerate the migration of samples through columns of densely packed microparticulate gel. Rapid qualitative analysis and an estimate of the amounts of cannabinoids present was achieved.

Cannabis↗