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Objective To evaluate the cell-mediated immune tissue reactions of mice model of chromoblastomycosis. Methods First we developed a murine model of chromoblastomycosis subcutaneous infection with F. pedrosoi inoculated into the footpads using immunocompetent and immunocompromised mice immuned by CTX, and then by immunohistochemistry methods analyzed the expression of cytokines IL-4, IL-10, TNF-α and IFN-γ at the seventh and thirtieth day, the expression of these cytokines at the same time in the healthy mice footpads were used as control. Results In the immunocompetent mice, The expression of IL-4, IL-10 and TNF-α was significantly higher when compared with healthy control at the seventh day,showing an up-regulation pattern of Th2 and Th1 type cellular immune functions with a predominance of the Th2 response. At the 30th day, the expression of IL-10 was significantly lower when compared with the 7th day and no difference with healthy controls, while IFN-γand TNF-α were gradually increased, the T cellmediated immune drives to Th1 response from Th2. In the immunocompromised mice, the expression of IL4 and IL-10 were significantly higher, meanwhile IFN-γwas lower than those in immunocompetent or healty mice, the levels of TNF-α was not significantly different fiom healty control at the 7th day, it showed that Th2 response was more increased with the Th1 responses was significantly inhibited in the early immune reactions. At the 30th day, the Th1 type cytokines IFN-γ and TNF-α were highly significantly higher than early stage but still lower than immunocompetent levels, the level of Th2 type cytokine IL-10 rradually decreased although it was still above the other two rroups. Conclusion In different immune state, there was an immune defence translation from the predominance of Th2 type cellular immunity to Th1 type in the process of murine model of chromoblastomycosis. Thl type cytokines which favors resistance to fungal disease, played a major role at controlling the development of chromoblastomycosis.
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Objective To study the difference in pathogenicity and genotype between two isolates of Veronaeae botryosa with different temperature tolerance. Methods Two strains of Veronaeae botryose were isolated from two patients with phaeohyphomycosis in Jiangsu and Henan province respectively. Of them, the Jiangsu strain could grow well at 37 ℃, but Henan strain could not grow at 36 ℃. Eighty mice were equally classified into immunocompetent and immune-suppressed (induced by cyclophosphamide) groups to be inoculated with the two strains of Veronaeae botryosa respectively. Ten mice remained uninoculated and served as the control. The general condition, growth and organic involvement of mice were observed for 4 weeks followed by the killing of surviving mice. Homogenated tissue samples were obtained from liver, spleen, lung, kidney and brain; then, tissue culture, direct microscopy and pathological examination were performed. Genomie DNA was extracted from tissue samples and subjected to random amplified polymor-phic DNA (RAPD) analysis. PCR was performed to amplify the intemal transcribed spacer (ITS) of rDNA followed by sequencing Results Systemic phaeohyphomycosis was induced in both immunocompetent and immune-suppressed mice by the Jiangsu strain of Veronaeae botryose; the mortality was 30% in immune-competent mice and 65% in immune-suppressed mice with statistical significance between the two groups. In immune-suppressed mice inoculated with the Jiangsu strain, the infection rate was 100% in the lung,signifi-cantly higher than in other organs; on direct microscopy the infection rate reached 64.7% in the liver, and 70.5% on tissue culture. There was no significant difference in the infection rate among these organs in immunocompetent mice inoculated with the Jiangsu strain, with the infection rate being 57.8% in the lung and 42.1% in the liver. Increased infection rate was observed in the lung of immune-suppressed mice com-pared with immunocompetent mice (P < 0.05). No definite infection was seen in immunoeompetent or immune-suppressed mice innoculated with the Henan strain. RAPD analysis and sequencing revealed that there was a base variation (A/G) at position 236 of ITS gene between the two strains. Conclusions The two strains of Veronaeae botryosa have different genotypes. Systemic phaeohyphomycosis can be caused in immunocompetent and immuno-suppressed mice by the Veronaeae botryosa isolate from Jiangsu Province; the mortality was higher in immuno-suppressed mice than in immunocompetent mice. The pathogenicity of Veronaeae botryose is associated with the immune status of hosts. In immuno-suppressed mice, lung is the organ most susceptible to infection by Veronaeae botryosa.
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Objective To investigate the genotype of Trichophyton rubrum isolated from children and adults with dermatophytosis,and to explore the relationship between the genotype and location of lesions as well as drug susceptability of T.rubrum.Methods Dermatophytes were isolated from 67 children and 88 adults who had been diagnosed with dermatophytosis by microscopy and fongal culture.DNA was extracted from the clinical isolates of T. mbrum and random amplification of polymorphic DNA(RAPD)assay was performed with two random primers.i.e.,OPA11 5'ACCCGACCTC3'and OPD18 5'GAGAGCC AAC3',respectively.PCR products were subjected to electrophoresis to identify the genotypes of clinical isolates.Broth microdilution method was applied to assess the in vitro susceptibility of T. rubrum isolates to eight antifungal agents:fluconazole,itraconazole,terbinafine,ketoconazole,liranaflate,butenafine,econazole and bifonazole.Results T. rubrum was isolated from 47 children and 62 adults with dermatophytosis.RAPD assay yielded clear and stable DNA band profile.With primer OPA 11,these T.rubrum isolates were classified into 4 genotypes,i.e.,Ⅰ a,Ⅱ a,Ⅲa and Ⅳa.Both type Ⅰ a and Ⅲa represented 41.94%of the T. rubrmn isolates from adults,while type Ⅰa 65.96%of those from children;there was a significant difference in the genotype distribution between the two groups(P＜0.05).Also,the genotype distilbution was statistically different for tinea corporis and tinea pedis(P＜0.01,＜0.05 respectively)between adults and children,however,no significant difierence was observed for onychomycosis and tinea cruris(both P＞0.05).In vitro susceptibility test showed that all antifungal agents were effective against these T. rubrum isolates.Among these antifungals,terbinafine had the highest efficacy,and fluconazole exhibited the lowest effect against these isolates.Moreover,a higher efficacy was observed for ketoconazole and fluconazole against T. rubrum of type Ⅰ a than against other types of T. rubrum,and for bifonazole against T. rubrum isolates of type Ⅱ a than against other types.while the efficacy of itraconazole was lower against T. rubmm isolates of type Ⅲ a than against other types.Conclusions T. rubrum is the main pathogenic microorganism in adults and children with dermatophytosis.In adults,Ⅰ a and Ⅲ a are the predominate types of T. rubrum associated with dermatophytosis,while Ⅰ a is the common type in children.All the 8 antifungals tested have a good efficacy for various genotypes of T. rubrum,whereas the efficacy of fluconazole,itraconazole,kctoconazole,terbinafine and bifonazole varies with the genotypes of T. rubrum.
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Objective To detect gene mutations in a family of congenital atrichia with papular lesions (APL). Methods Polymerase chain reaction and DNA sequencing were used to search for mutations in the HR gene (a causative gene of APL), the CJB6 gene, and the CDSN gene. Results No mutation was found in these three genes except for single nucleotide polymorphisms (SNPs) in the HR and CDSN genes. Conclusion No mutation is identified in the HR, CJB6 or CDSN gene in this family affected by congenital APL.