Mixed immune response induced in rodents by two naked DNA genes coding formycobacterial glycosylated proteins

Two genes of Mycobacterium tuberculosis, apa (Rv1860) and pro (Rv1796), cod ing for two glycosylated excreted proteins have been injected to mice and g uinea pigs. They produce an extended immunological response of Th1 and Th2 types. Despite the fact that mycobacterial glycosylation is necessary for a high level of delayed-type hypersensitivity (DTH) reaction, plasmids beari ng each of the two genes induced an elevated level of DTH sensitization. An inverse relation between the CpG-N hexamer cluster frequency and the prote ctive effect of injected genes is described. A comparison of the strength o f several eukaryotic promoters based on the diameter of the DTH reaction sh ows that CMVIE followed by the ubiquitin promoter are the most efficient am ong those tested. A significant protective effect (0.7 log unit CFU) in mic e was found for the apa gene while the pro gene had no effect. (C) 2001 Els evier Science Ltd. All rights reserved.