Objective To study the application of P1 adhesin protein epitopes in diagnosis of Mycoplasma pneumoniae(Mp) infected patient. Methods The major epitope(P1-534) of P1 adhesin protein were predicted by ProPred and ANTIGENIC according to its primary structure. The high value fragment was cloned into a constructed recombinant vector. The gene was induced to express fusion protein in E. coli host strain BL21(DE3) and the fusion protein was identified by Western blot. BALB/c mice were immunized with purified protein to test its immunogenicity. Then the purified protein was used as antigen to test the serum of Mp infected patient by ELISA, and compared with the Mp whole cell antigen. Results The P1-534 protein was successfully expressed and purified. ELISA data showed that P1-534 protein could elicit high levels of IgG in immunized mice, the sensitivity and specificity of P1-534 were determined to be 85.00% and 97.67%, while the Mp whole cell antigen were 72.50% and 74.42%. Conclusion The results conformed that the recombinant epitope has certain immunogenicity,and its sensitivity and specificity are better than Mp whole cell antigen. P1-534 protein can be used as an antigen for immunodiagnosis of Mp infection.

pneumococcal infections for children. S. pneumoniae was sensitive to penicillin, which was still the first choice of treatment for S. pneumoniae infections. All the isolates were resistant to erythromycin, and ermB was the dominant mechanism of macrolide-resistance.

Objective To prepare 99 Tcm-HYNIC-c( isoDGRKy) as a SPECT/CT imaging molecu-lar probe targeting integrin αvβ3 , and evaluate its biodistribution and feasibility on SPECT/CT imaging for integrinαvβ3-positive tumor in U87MG human glioma xenograft mouse models. Methods The bifunctional chelator HYNIC was conjugated to c( isoDGRKy) , and tricine and TPPTS were used as coligands for 99 Tcm labeling to prepare 99 Tcm-HYNIC-c( isoDGRKy) . The radiochemical purity and stability of the product were measured. The expression of integrin αvβ3 and binding affinity ( half maximal inhibitory concentration, IC50 ) of c ( isoDGRKy ) was detected in U87MG cells by cell experiments in vitro. Biodistribution and SPECT/CT imaging of 99 Tcm-HYNIC-c( isoDGRKy) including blocking experiments were performed respec-tively in nude mice bearing U87MG human glioma xenografts. Results The radiochemical purity of 99 Tcm-HYNIC-c( isoDGRKy) was over 99%, and was still over 99% after 4 h incubation in saline at room temper-ature. Flow cytometry assay showed that U87MG cells were integrinαvβ3-positive ( expressive rate:70%) . The IC50 of c(isoDGRKy) was 6.67×10-8 mol/L. Biodistribution results showed 99Tcm-HYNIC-c(isoDGRKy) with a rapid clearance from blood was excreted mainly via the kidneys. The 99 Tcm-HYNIC-c( isoDGRKy) uptake values in U87MG tumors were (7.31±1.42) and (1.09±0.11) %ID/g at 15 and 45 min post-injection re-spectively, and tumor-to-muscle ratio reached 5.01±1.47 at 15 min post-injection. The tumors were clearlyvisualized with low background from 0.5 to 1 h post-injection in tumor bearing mice. In the blocking experi-ment, the tumor was barely visualized after co-injection of excess cold c(RGDfK) peptide with 99Tcm-HYNIC-c(isoDGRKy). Conclusions 99Tcm-HYNIC-c(isoDGRKy) may be easily and steadily prepared. It may be a RGD-like promising SPECT/CT imaging probe for integrinαvβ3-positive tumor.