The antigenic characteristics of Salmonella typhi L forms

The study of the possibility of detecting the specific antigens of S. typhi L forms has revealed that out of three destructive methods under study (osmotic lysis, freezing-thawing, sonication) only ultrasonic disintegration has proved to be effective for S. typhi L forms. Three specific fractions capable of interacting only with specific antibodies to S. typhi L forms have been revealed in the course of chromatographic separation of the soluble antigenic complex of S. typhi stable L forms and the subsequent analysis of the fractions thus obtained in the enzyme immunoassay.     

Characterization of a Distinct Population of Circulating Human Non-Adherent Endothelial Forming Cells and Their Recruitment via Intercellular Adhesion Molecule-3

Circulating vascular progenitor cells contribute to the pathological vasculogenesis of cancer whilst on the other hand offer much promise in therapeutic revascularization in post-occlusion intervention in cardiovascular disease. However, their characterization has been hampered by the many variables to produce them as well as their described phenotypic and functional heterogeneity. Herein we have isolated, enriched for and then characterized a human umbilical cord blood derived CD133⁺ population of non-adherent endothelial forming cells (naEFCs) which expressed the hematopoietic progenitor cell markers (CD133, CD34, CD117, CD90 and CD38) together with mature endothelial cell markers (VEGFR2, CD144 and CD31). These cells also expressed low levels of CD45 but did not express the lymphoid markers (CD3, CD4, CD8) or myeloid markers (CD11b and CD14) which distinguishes them from ‘early’ endothelial progenitor cells (EPCs). Functional studies demonstrated that these naEFCs (i) bound Ulex europaeus lectin, (ii) demonstrated acetylated-low density lipoprotein uptake, (iii) increased vascular cell adhesion molecule (VCAM-1) surface expression in response to tumor necrosis factor and (iv) in co-culture with mature endothelial cells increased the number of tubes, tubule branching and loops in a 3-dimensional in vitro matrix. More importantly, naEFCs placed in vivo generated new lumen containing vasculature lined by CD144 expressing human endothelial cells (ECs). Extensive genomic and proteomic analyses of the naEFCs showed that intercellular adhesion molecule (ICAM)-3 is expressed on their cell surface but not on mature endothelial cells. Furthermore, functional analysis demonstrated that ICAM-3 mediated the rolling and adhesive events of the naEFCs under shear stress. We suggest that the distinct population of naEFCs identified and characterized here represents a new valuable therapeutic target to control aberrant vasculogenesis.     

Preventive properties of the blood sera from persons vaccinated with a Proteus vaccine made from soluble antigen complexes

In experiments of the passive protection of mice the protective properties of sera obtained from humans before and after their immunization with Proteus vaccine used as a monopreparation or in combination with staphylococcal toxoid and/or pyoimmunogen were studied. When introduced in a single subcutaneous injection, Proteus vaccine prepared from soluble antigenic complexes ensured an increase in the protective properties of sera. The second injection of the vaccine essentially enhanced the protective potency of the sera of the immunized donors. The therapeutic injection of Proteus vaccine ensured the essential increase of the protective properties of the sera. This increase could be experimentally detected within at least 25-30 days from the beginning of immunization. The immunization of volunteers with Proteus vaccine in combination with pyoimmunogen and adsorbed staphylococcal toxoid ensured the maximum increase of the protective properties of their sera.     

Microecology of the gastrointestinal tract of chronic enteritis patients

The results obtained in the simultaneous study of the microbiology of different sections of the gastrointestinal tract (the oral cavity, the stomach, the large and small intestines) in chronic enteritis patients, as well as in the study of biopsy mucosa samples from the small intestine of such patients, are presented. This method has been shown to give a complete picture indicating both the severity of dysbiotic disturbances in the patient and the degree of their spread in the alimentary canal, which should be taken into account in clinical practice for the determination of the severity of the disease, the rational course of treatment and the time of the discharge of the patient from the hospital.     

Proteus peritonitis-bacteremia in mice--a model for studying postvaccinal Proteus immunity

The dynamics of the formation of postvaccinal immunity after immunization with preparations obtained with the use of hydroxylamine (HA) preparations from Proteus strains of different O serogroups, Salmonella minnesota Re-mutant and the common antimicrobial antigen isolated from Escherichia coli 14 has been studied on mice with Proteus peritonitis-bacteremia used as a model. The study has revealed that intraperitoneal immunization with Proteus HA preparations stimulates the phagocytic activity of peritoneal mononuclear cells in mice and induces an increase in the titers of specific O antibodies. Proteus antigens ensure the formation of anti-Proteus immunity, preventing the death of the animals from peritonitis-bacteremia. The protection of mice from such infection resulting from the injection of the common antigens of gram-negative bacteria is considerably less. These data are indicative of the possibility of using Proteus peritonitis-bacteremia as a model for the study of the protective potency of Proteus vaccines.