Washington University

The United States Government As Represented by the Department of Veterans Affairs

The Administrators of the Tulane Educational Fund

Cheryl Anne Nickerson

Roy Curtiss, Iii

Timothy Grant Hammond

The present invention provides methods for utilizing a form of optimized suspension culture to examine the infectivity of pathogenic organisms and agents in human cells and tissues. Also provided are methods using a rotating wall vessel to predict chemosensitivity of cells and tissues to toxins and chemotherapeutic agents. These culture conditions potentiate spatial colocalization and three-dimensional assembly of individual cells into large aggregates which more closely resemble the in vivo tissue equivalent. In this environment, dissociated cells can assemble and differentiate into macroscopic tissue aggregates several millimeters in size. These culture conditions allow for better cellular differentiation and formation of three-dimensional cellular aggregates, more efficient cell-to-cell interactions, the in in vivo-like exchange of growth factors and greater molecular scaffolding facilitating mechanical stability for cells. The suspension culture system offers a new approach for studying microbial infectivity from the perspective of the host-pathogen interaction and also for analyzing chemosensitivity to toxins and chemotherapeutic agents.

Methods for modeling infectious disease and chemosensitivity in cultured cells and tissues

Attenuated immunogenic bacteria having an RpoSphenotype, in particular,serotypehaving an RpoSphenotype and methods therefor are disclosed. Thehave in addition to an RpoSphenotype, an inactivating mutation in one or more genes which render the microbe attenuated, and a recombinant gene capable of expressing a desired protein. Theare attenuated and have high immunogenicity so that they can be used in vaccines and as delivery vehicles for genes and gene products. Also disclosed are methods for preparing the vaccine delivery vehicles.

Recombinant vaccines comprising immunogenic attenuated bacteria having RpoS positive phenotype

Attenuated immunogenic bacteria having an RpoS phenotype, in particular, serotype Typhi having an RpoS phenotype and methods therefor are disclosed. The Salmonella have in addition to an RpoS phenotype, an inactivating mutation in one or more genes which render the microbe attenuated, and a recombinant gene capable of expressing a desired protein. The Salmonella are attenuated and have high immunogenicity so that they can be used in vaccines and as delivery vehicles for genes and gene products. Also disclosed are methods for preparing the vaccine delivery vehicles.

Recombinant vaccines comprising immunogenic attenuated bacteria having RPOS positive phenotype

Avirulent immunogenic Salmonella enterica serotype Typhi and methods therefor are disclosed. The Salmonella have an RpoS.sup.+ phenotype, an inactivating mutation in one or more genes which renders the microbe avirulent, and a recombinant gene capable of expressing a desired protein. The Salmonella are avirulent and have high immunogenicity so that they can be used in vaccines and as delivery vehicles for the desired antigen. Also disclosed are methods for preparing the Salmonella and vaccine delivery vehicles therefor.

Growing community of inventors

River Ridge, LA, United States of America

Cheryl Anne Nickerson