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Two pairs of primers for diagnosis of coccidioidomycosis using the method of PCR were constructed. One pair was used for identification of the two species of Coccidioides (C. immitis and C. posadasil) on the basis of MBP-1 gene. The other pair was chosen on the basis of SOWgp82 gene, which encodes an immunodominant, spherule outer wall glycoprotein for detecting only C. posadasii. The used primers allowed the agents of coccidioidomycosis to be detected using PCR with high sensitivity and specificity. The effective method of isolation of fungus DNA from soil contaminated with arthroconidia of Coccidioides spp. was developed. It includes guanidinthiocyanate-phenol-chloroform deproteinization followed by DNA purification using nuclear sorption.

In this work conditions for the reproduction of hybridoma technology, specially adapted to C. neoformans, for obtaining monoclonal hybridomas (McAb) to diagnostically significant antigens of C. neoformans, the infective agent of cryptococcosis, are presented. The advantages of using the short-time cycle of stimulation of mouse B lymphocytes with low doses of C. neoformans capsular polysaccharide and the effectiveness of the hybridization of mouse spleen cells with myeloma cells, line Sp2/0, are shown. Four lines of stable hybridomas, producing McAb to different epitopes of C. neoformans surface antigens, have been obtained. The specific activity of McAb has been studied in the indirect immunofluorescence assay, the cytochemical and solid-phase enzyme immunoassays (EIA). McAb 3E2, Cr2 and 2G9 have been shown to be suitable for use in diagnostic EIA systems.

The study has shown that the growth of many soil fungi is inhibited by the effect of substances which are produced into the environment by some bacilli-saprotrophs. Besides, these substances can bring about a dimorphism of the Trichoderma, Blastomyces, Emmonsia, Alternaria and Verticillium fungi from the mycelial form into the yeast form, which results in the death of the fungi. The existence of bacilli capable of producing the inhibitory substances, in the soil in the territory of the USSR may explain, to a certain extent, the absence of the coccidioidomycosis and North American blastomycosis agents pathogenic for people and many animals.

It is shown that there are specific substances produced and secreted into the environment by saprotrophic bacilli. These inhibit the growth of the coccidioidal fungus in its mycelial form and some cells are converted into the yeast form, which leads to the destruction of the fungi (in natural environment) or, if the conditions allow, to their growth in the yeast form. This phenomenon, existence of a large amount of bacilli antagonistic to Coccidioides immitis, may be one of reasons why the latter has not been isolated so far from the soil in the territory of the USSR.