Photochemical treatment of platelet concentrates with amotosalen and long-wavelength ultraviolet light inactivates a broad spectrum of pathogenic bacteria.

BACKGROUND: Bacterial contamination of platelet (PLT) concentrates can result in transfusion-transmitted sepsis. A photochemical treatment (PCT) process with amotosalen HCl and long-wavelength ultraviolet light (UVA), which cross-links nucleic acids, was developed to inactivate bacteria and other pathogens in PLT concentrates. STUDY DESIGN AND METHODS: High titers of pathogenic aerobic and anaerobic Gram-positive bacteria (10 species), aerobic Gram-negative bacteria (7 species), and spirochetes (2 species) were added to single-donor PLT concentrates containing 3.0 x 10(11) to 6.0 x 10(11) PLTs in approximately 300 mL of 35 percent plasma and 65 percent PLT additive solution (InterSol, Baxter Healthcare) or saline. After PCT with 150 micro mol per L amotosalen and 3 J per cm(2) UVA, residual bacterial levels were detected by sensitive microbiologic methods. RESULTS: The level of inactivation of viable bacteria was expressed as log reduction. Log reduction of Gram-positive bacteria for Staphylococcus epidermidis was > 6.6; for Staphylococcus aureus, 6.6; for Streptococcus pyogenes, > 6.8; for Listeria monocytogenes, > 6.3; for Corynebacterium minutissimum, > 6.3; for Bacillus cereus (vegetative), > 5.5; for Lactobacillus sp., > 6.4; for Bifidobacterium adolescentis, > 6.0; for Propionibacterium acnes, > 6.2; and for Clostridium perfringens, > 6.5. Log reduction of Gram-negative bacteria for Escherichia coli was > 6.4; for Serratia marcescens, > 6.7; for Klebsiella pneumoniae, > 5.6; for Pseudomonas aeruginosa, 4.5; for Salmonella choleraesuis, > 6.2; for Yersinia enterocolitica, > 5.9; and for Enterobacter cloacae, 5.9. Log reduction of spirochetes for Treponema pallidum was 6.8 to 7.0, and for Borrelia burgdorferi, > 6.9. CONCLUSION: PCT inactivates high levels of a broad spectrum of pathogenic bacteria. The inactivation of bacteria in PLT concentrates offers the potential to prospectively prevent PLT-transfusion-associated bacteremia.

[The effect of magnetoregulated microfields on Treponema pallidum. 2]. / Vliianie mikropolei magnitouporiadochennykh sredstv na blednuiu treponemu. Soobshchenie 2.

The authors proceed with their studies of magnetic microfields detected round T. pallidum and of the interactions of these fields with the biologic objects round the treponemas; these studies will prompt approaches to physiotherapeutic management of infectious diseases, making use of a new (for medicine) source of physical fields. They have revealed that T. pallidum fluorescence intensity and the width of the 'fan' of T. pallidum on the domain structures of ferrite/garnet films indicates the degree of T. pallidum pathogeneity.

[Attempts at developing a syphilis vaccine (author's transl)]. / Die Suche nach einer Vakzine gegen die Syphilis.

Numerous investigators tried over the years to induce artifically immunity against syphilis by use of a variety of treponema preparations. None of these immunization experiments performed by different means and routes provided clear evidence of acquired immunity in animals and humans given various vaccine preparations against challenge with even minimal doses of virulent T. pallidum. In recent years, however, promising results have been obtained in the immunization study. Two types of syphilis vaccine have been developed which were found very effective in conferring a protection against syphilitic infection on rabbits: (1) the first vaccine contains T. pallidum attenuated by gamma irradiation, and the other one (2) contains T. pallidum killed by penicillin. In addition, it has been demonstrated that the immunogenic activity of T. pallidum is related to their very labile protein component. Pretty much is also known on the factors influencing the immune response of artificially immunized rabbits, and on the immunological mechanisms underlying the development of syphilis immunity.

Immunity in experimental syphilis. IV. Serological reactivity of antigens extracted from gamm-irradiated Treponema pallidum and Treponema reiteri.

Miller, James N. (University of California School of Medicine, Los Angeles), J. H. De Bruijn, and J. H. Bekker. Immunity in experimental syphilis. IV. Serological reactivity of antigens extracted from gamma-irradiated Treponema pallidum and Treponema reiteri. J. Bacteriol. 91:583-587. 1966.-Ultrasonic lysate preparations extracted from virulent Treponema pallidum, Nichols strain, suspensions exposed to 652,800 R of gamma-irradiation exhibited a loss in the serological reactivity of their heat-labile antigens; the heat-stable components of both the lysate and residue antigens were unaffected. The activity of heat-stable, cardiolipin T. pallidum complement-fixing antigen obtained from similarly irradiated organisms was also unaltered. gamma-Irradiation of the cultivable Treponema reiteri with dosages as high as 6,500,000 R failed to alter serologically either the heat-labile or heat-stable component of its lipopolysaccharide-protein (Reiter protein) antigen. The reactivity of the lipopolysaccharide portion of the Reiter protein complex with an antiserum to T. pallidum Nichols indicates previously unsuspected antigenic differences between the rabbit-adapted Nichols strain of the organism and so-called "wild" human strains of T. pallidum in which this antigen is generally absent.