Therapy with Immunogens
Development of Methods for Therapy of Chronic Melioidosis with Burkholderia Specific Immunoges
Tech Area / Field
8 Project completed
Senior Project Manager
Frenkel B M
State Research Center for Applied Microbiology, Russia, Moscow reg., Obolensk
- USAMRIID, USA, MD, Fort Detrick
Project summaryRepeated therapy of melioidosis with antibiotics does not, as a rule, guarantee the complete remission of chronic disease, although in some cases a success can be achieved. The project authors support a viewpoint that the most effective method of chronic melioidosis therapy should involve a combination of methods to activize specific immune reactions and methods of antibacterial therapy.
Increase of the efficiency of antibacterial therapy of chronic melioidosis by specific stimulation of the immune system with identified immunosuppressor admixture-free Burkholderia immunogens is the major objective of the project proposed. Along with the search for immunodominant components, -the project suggests the identification of diagnostic Burkholderia antigens and immunosuppressors.
In order to meet these objectives the following tasks will be fulfilled:
- a number of highly-purified major immunogens, including outer membrane proteins will be isolated from the serologically typical strains of Burkholderia mallei, Burkholderia pseudomallei and Burkholderia cepacia;
- the strength of immunity induced by immunogens in vivo will be evaluated by using a number of virulent Burkholderia pseudomallei strains;
- optimal composition of Eurkholderia immunogens will be selected;
- laboratory studies of the immunogen composition safety will be performed on model animals;
- efficiency of specific immunotherapy in combination with antibacterial preparations will be evaluated on chronic melioidosis model;
- mathematical analysis of functional recovery of the immune and other systems of the organism after combined therapy of chronic melioidosis will be conducted.
Reversed phase HPLC will be predominantly used for isolation and purification of antigens. Porins will be determined by the ability to form pores in bilayer lipid membranes.
Preliminary selection of major immunogens will be carried out according to the ability of the antigens to induce delayed-type hypersensitivity in model animals.
Protective activity of the immunogens composition will be estimated after first and second vaccination of model animals with Burkholdeha pseudomallei strains of different virulence in dose-effect experiments. Repeated administration of a complex of immunogens will be followed by the control of allergic and autoimmune states as well as by the control of heterologous antigen sensitivity changes.
Antibacterial agents for immuno-antibioticotherapy will be selected with regard to their ability to penetrate into the host cells and the absence of direct and mediated effects on the functions of phagocyting cells and immune response in general.
Increase of frequency of eradication of the causatinve agent from the groups of model animals after treatment with antibacterial agents on the background of the immune system stimulation will be a criterion for the efficiency of the immunotherapy. Eradication control will be performed by bacteriological methods (including L-form detection) after provocation of the acute form by immunosuppressive agent (cyclophosphamide) injection as well as by in vivo and in vitro delayed-type hypersensitivity testing.
The choice of antibacterial preparations for combined therapy with immunogens and antibiotics will be governed by the results of mathematical analysis of the dynamic changes of immune reaction levels and by the results of clinical and laboratory testings of infected model animals during combined therapy.
The final objective of the project is the development of a composition of highly immunogenic biopolymers from Burkholderia mallei, Burkholderia pseudomallei and, possibly, from Burkholderia cepacia to be used for therapy and elaboration of scheme of effective combined immunochemotherapy of chronic melioidosis, a typical example of oportunistic infection tended to be of chronic character.
In addition, antigens possessing immunosuppresive properties and antigens promising for the development of commercial diagnostic preparations will be isolated.
Proposals for Potential Foreign Collaborators
- exchange of scientific information;
- practical study of SRCAM's researchers in western research centers;
- cooperative investigations.