Epitope mapping and characterization of a novel Nsp10-specific monoclonal antibody that differentiates genotype 2 PRRSV from genotype 1 PRRSV
VIROLOGY JOURNAL
Authors: Zhang, Zhibang; Wen, Xuexia; Dong, Jianguo; Ge, Xinna; Zhou, Lei; Yang, Hanchun; Guo, Xin
Abstract
Background: Porcine reproductive and respiratory syndrome virus (PRRSV), the causative agent of PRRS, has two distinct and highly diverse genotypes (genotype 1 and genotype 2) in the field. Accurate diagnosis and differentiation of the two genotypes of PRRSV are critical to the effective prevention and control of PRRS. The non-structural protein 10 (Nsp10) plays a vital role in viral replication and is one of the most conserved proteins of PRRSV, thus constituting a good candidate for PRRSV diagnosis. Results: In this study, we generated a monoclonal antibody (mAb) 4D9 against Nsp10 by immunizing BALB/c mice with purified recombinant Nsp10 expressed by an Escherichia coli system. Through fine epitope mapping of mAb 4D9 using a panel of eukaryotic expressed polypeptides with GFP-tags, we identified the motif (286)AIQPDYRDKL(295) as the minimal unit of the linear B-cell epitope recognized by mAb 4D9. Protein sequence alignment indicated that 286AIQPDYRDKL295 was highly conserved in genotype 2 PRRSV strains, whereas genotype 1 PRRSV strains had variable amino acids in this motif. Furthermore, a mutant of the motif carrying two constant amino acids of genotype 1 PRRSV, Cys290 and Glu293, failed to react with mAb 4D9. More importantly, the mAb 4D9 could differentiate genotype 2 PRRSV strains from genotype 1 PRRSV strains using Western blotting and immunofluorescence analysis. Conclusion: Our findings suggest that Nsp10-specific mAb generated in this study could be a useful tool for basic research and may facilitate the establishment of diagnostic methods to discriminate between genotype 1 and genotype 2 PRRSV infection.
Antitumor efficacy of EDTA co-treatment with cisplatin in tumor-bearing mice
BRAZILIAN JOURNAL OF PHARMACEUTICAL SCIENCES
Authors: El-Naggar, Sabry Ali; El-Said, Karim Samy
Abstract
Ethylenediamine tetraacetic acid (EDTA) is used in various medical applications. The aim of this study is to investigate the antitumor efficacy of EDTA alone or with cisplatin (Cis). Fifty male albino mice were used to assess the median lethal dose (LD50) of EDTA via intraperitoneal (i.p) injection. To determine the antitumor activity, fifty female albino mice were divided into five groups as the following; Group 1 (Gp1) was negative control; (Gp2-5) inoculated i.p with 2x10(6) Ehrlich Ascites Carcinoma (EAC) cells/mouse. After one day, Gp3, Gp4 and Gp5 injected with Cis (2 mg/kg), EDTA (25 mg/kg) and Cis (2 mg/kg)/EDTA (25 mg/kg) for six days, respectively. At day 14, all groups were sacrificed to assess the tumor profile, liver enzymes (alanine transaminases and aspartate transaminases), kidney function (urea and creatinine) and electrolytes (Na+, K+ and Ca2+). The results showed that the i.p LD50 of EDTA was 250 mg/kg. Treatment with EDTA alone did not show any antitumor activity and did not interfere with the antitumor efficacy of Cis. Biochemical findings revealed that EDTA had mild toxicity on liver and kidneys functions. In summary, EDTA had no antitumor effect and did not alter the Cis efficacy.