Abstract: A method is provided for folding chemically synthesized polypeptides having two or more derivatized cysteine residues by contacting with a reducing agent in a folding buffer having a predetermined pH and temperature.

Abstract: The present invention relates to a vaccine against malaria comprising a polypeptide having the amino acid sequence of the C-terminal part of the circumsporozoite protein of a Plasmodium species, in which polypeptide one or more pairs of cysteine residues are oxidized, and optionally a suitable carrier and/or adjuvant and/or biodegradable microcapsules for use in humans.

Abstract: An immunological response potentiation process is disclosed for synthetic or genetically engineered antigens having low immunogenicity. The antigen is embedded into biodegradable microparticles, and the antigen-loaded microparticles are dispersed in a biodegradable medium. When parenterally administered, the antigen-loaded microparticles trigger a potentiated antibody, TH-lymphocyte and Tc-lymphocyte response, as compared to an aqueous antigen solution. The extent of immunological potentiation is at least comparable with that attained by Incomplete Freund's adjuvant compositions. Linear B-TH-cell epitopes, linear Tc-cell epitopes, dimers and multimers of those epitopes, and mixtures thereof, are used as low immunogenicity antigens. The microparticles are based on biodegradable biopolymers such as polyester, polyanhydride, and polyorthoester.

Abstract: The present invention relates to a vaccine against malaria comprising a polypeptide having the amino acid sequence of the C-terminal part of the circumsporozoite protein of a Plasmodium species, in which polypeptide one or more pairs of cysteine residues are oxidized, and optionally a suitable carrier and/or adjuvant and/or biodegradable microcapsules for use in humans.

Abstract: The invention relates to the use of the regulatory subunit (R) of the cAMP dependent protein kinase (PKA) from Dictyostelium discoideum for cAMP detection. It includes constructs for expression of the R-subunit in E. coli and fusion to green fluorescent proteins (GFP). Fluorescence energy transfer is used as a way to monitor cAMP binding, either by using fluorescently labelled cAMP or cGMP, or by using mutant GFPs with modified absorption and emission spectra. FRET changes upon cAMP binding will allow measurement of cAMP level either in vitro or within living cells.

Abstract: High expression levels and simple downstream processing are essential for the production of recombinant proteins at low cost. We report here a new expression vector which allows production of fusion proteins in Dictyostelium discoideum. We made use of the ability of Discoidin I to bind Sepharose-4B to set up a nearly single step purification procedure. The Discoidin I coding region was fused to several forms of the malaria parasite CSP gene in a Dictyostelium expression vector, allowing intracellular accumulation as well as partial secretion via a pathway unrelated to the endoplasmic reticulum and Golgi. The fusion proteins present in cell extracts were affinity-purified over Sepharose-4B columns. Addition of a signal peptide allowed endoplasmic reticulum targeting and glycosylation of the fusion protein. Inclusion of a thrombin cleavage site allowed to cleave Discoidin from the CSP protein. The use of stable and low cost Sepharose 4B as affinity matrix should allow large-scale preparations.

Abstract: The invention relates to the use of the regulatory subunit (R) of the CAMP dependent protein kinase (PKA) from Dictyostelium discoideum for cAMP detection. It includes constructs for expression of the R-subunit in E. coli and fusion to green fluorescent proteins (GFP). Fluorescence energy transfer is used as a way to monitor cAMP binding, either by using fluorescently labelled cAMP or cGMP, or by using mutant GFPs with modified absorption and emission spectra. FRET changes upon cAMP binding will allow measurement of cAMP level either in vitro or within living cells.

Abstract: A recombinant polypeptide comprising a polypeptide which has added thereto a glycoxyl-phosphatidylinositol anchor structure, said polypeptide demonstrating a greater immune response than the corresponding polypeptide without the anchor. The polypeptide may be a parasite antigen such as a Plasmodium falciparum polypeptide. Recombinant vectors comprising the DNA sequence encoding the polypeptide with a glycolipid anchor addition sequence and host cells based thereon are also disclosed as well as vaccines and methods of inducing an immune response based on the polypeptides.

Abstract: The invention relates to recombinant DNA molecules comprising a Dictyostelium discoideum homologous promoter region, a heterologous DNA sequence with a Dictyostelium discoideum homologous peptide sequence capable of functioning as a leader peptide sequence positioned upstream thereof and in proper reading frame therewith, and a Dictyostelium discoideum homologous termination region, the heterologous DNA sequence encoding the desired functional polypeptide or intermediate thereof, said DNA sequence being positioned downstream from the promoter region and said termination region being positioned downstream from the DNA sequence. The invention also provides recombinant dictyostelid hosts as well as methods for preparing recombinant DNA molecules of the invention and for expressing recombinant polypeptides encoded by said recombinant DNA molecules in dictyostelid hosts. The invention in particular relates to the expression of the CS protein of Plasmodium falciparum.