Nucleases as a barrier to gene silencing in the cotton boll weevil, Anthonomus grandis.

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Characterization of fossilized relatives of the White Spot Syndrome Virus in genomes of decapod crustaceans

$\bf Background:$ The White Spot Syndrome Virus (WSSV) is an important pathogen that infects a variety of decapod species and causes a highly contagious disease in penaeid shrimps. Mass mortalities caused by WSSV have pronounced commercial impact on shrimp aquaculture. Until now WSSV is the only known member of the virus family Nimaviridae, a group with obscure phylogenetic affinities. Its isolated position makes WSSV studies challenging due to large number of genes without homology in other viruses or cellular organisms. $\bf Results:$ Here we report the discovery of an unusually large amount of sequences with high similarity to WSSV in a genomic library from the Jamaican bromeliad crab $\textit {Metopaulias depressus}$. $\textit {De novo}$ assembly of these sequences allowed for the partial reconstruction of the genome of this endogenized virus with total length of 200 kbp encompassed in three scaffolds. The genome includes at least 68 putative open reading frames with homology in WSSV, most of which are intact. Among these, twelve orthologs of WSSV genes coding for non-structural proteins and nine genes known to code for the major components of the WSSV virion were discovered. Together with reanalysis of two similar cases of WSSV-like sequences in penaeid shrimp genomic libraries, our data allowed comparison of gene composition and gene order between different lineages related to WSSV. Furthermore, screening of published sequence databases revealed sequences with highest similarity to WSSV and the newly described virus in genomic libraries of at least three further decapod species. Analysis of the viral sequences detected in decapods suggests that they are less a result of contemporary WSSV infection, but rather originate from ancestral infection events. Phylogenetic analyses suggest that genes were acquired repeatedly by divergent viruses or viral strains of the Nimaviridae. $\bf Conclusions:$ Our results shed new light on the evolution of the Nimaviridae and point to a long association of this viral group with decapod crustaceans

Generation of Virus- and dsRNA-Derived siRNAs with Species-Dependent Length in Insects

Double-stranded RNA (dsRNA) molecules of viral origin trigger a post-transcriptional gene-silencing mechanism called RNA interference (RNAi). Specifically, virally derived dsRNA is recognized and cleaved by the enzyme Dicer2 into short interfering RNAs (siRNAs), which further direct sequence-specific RNA silencing, ultimately silencing replication of the virus. Notably, RNAi can also be artificially triggered by the delivery of gene-specific dsRNA, thereby leading to endogenous gene silencing. This is a widely used technology that holds great potential to contribute to novel pest control strategies. In this regard, research efforts have been set to find methods to efficiently trigger RNAi in the field. In this article, we demonstrate the generation of dsRNA- and/or virus-derived siRNAs-the main RNAi effectors-in six insect species belonging to five economically important orders (Lepidoptera, Orthoptera, Hymenoptera, Coleoptera, and Diptera). In addition, we describe that the siRNA length distribution is species-dependent. Taken together, our results reveal interspecies variability in the (antiviral) RNAi mechanism in insects and show promise to contribute to future research on (viral-based) RNAi-triggering mechanisms in this class of animals.status: publishe

Radioimmunoscintigraphy of recurrent, metastatic, or occult colorectal cancer with technetium 99m-labeled totally human monoclonal antibody 88BV59: results of pivotal, phase III multicenter studies.

PURPOSE: To assess the performance and potential clinical impact of a totally human monoclonal antibody, 88BV59 (HumaSPECT) (INTRACEL, Corp, Rockville, MD), in 202 assessable presurgical patients with recurrent, metastatic, or occult colorectal cancer. METHODS: 88BV59, labeled with technetium Tc 99m (99mTc) (HumaSPECT-Tc), was injected intravenously, and planar and single photon emission tomography (SPECT) images were obtained 14 to 20 hours postinjection. Surgical and pathologic verification of tumor were used as the standard against which the performance of HumaSPECT-Tc imaging and computed tomography (CT) analysis were evaluated. RESULTS: All patients entered onto the recurrent disease study had at least one tumor site defined on CT. The sensitivity of HumaSPECT-Tc in those CT-positive patients was 87%. The specificity of HumaSPECT-Tc was 57% compared with 17% for CT and the difference was statistically significant (P \u3c .001). The diagnostic information provided by HumaSPECT-Tc significantly (P \u3c .001) improved the accuracy of the identification of resectable and nonresectable disease over that of CT (80% v 62%). HumaSPECT-Tc scans resulted in a significant (P \u3c .001) reduction versus CT in terms of the proportion of patients understaged (27% v 41%) and overstaged (4% v 26%). In patients with occult disease (increasing carcinoembryonic antigen [CEA] titer, negative diagnostic work-up, negative CT), HumaSPECT-Tc correctly identified disease in 15 of 22 (68%) patients. HumaSPECT-Tc images provided additional clinical data that would have affected patient management decisions in 40 of 202 (19.8%) patients. In 365 patients who received 88BV59, only a single detectable human anti-human antibody (HAHA) response (90 ng/mL) at 9 weeks postinfusion was observed. CONCLUSION: HumaSPECT-Tc can provide important and accurate information about the presence and location of disease in patients with a high clinical suspicion of metastatic or recurrent colorectal cancer and either positive (known disease) or negative (occult disease) CT scans

Radioimmunoscintigraphy of recurrent, metastatic, or occult colorectal cancer with technetium 99m-labeled totally human monoclonal antibody 88BV59: results of pivotal, phase III multicenter studies.

PURPOSE: To assess the performance and potential clinical impact of a totally human monoclonal antibody, 88BV59 (HumaSPECT) (INTRACEL, Corp, Rockville, MD), in 202 assessable presurgical patients with recurrent, metastatic, or occult colorectal cancer. METHODS: 88BV59, labeled with technetium Tc 99m (99mTc) (HumaSPECT-Tc), was injected intravenously, and planar and single photon emission tomography (SPECT) images were obtained 14 to 20 hours postinjection. Surgical and pathologic verification of tumor were used as the standard against which the performance of HumaSPECT-Tc imaging and computed tomography (CT) analysis were evaluated. RESULTS: All patients entered onto the recurrent disease study had at least one tumor site defined on CT. The sensitivity of HumaSPECT-Tc in those CT-positive patients was 87%. The specificity of HumaSPECT-Tc was 57% compared with 17% for CT and the difference was statistically significant (P \u3c .001). The diagnostic information provided by HumaSPECT-Tc significantly (P \u3c .001) improved the accuracy of the identification of resectable and nonresectable disease over that of CT (80% v 62%). HumaSPECT-Tc scans resulted in a significant (P \u3c .001) reduction versus CT in terms of the proportion of patients understaged (27% v 41%) and overstaged (4% v 26%). In patients with occult disease (increasing carcinoembryonic antigen [CEA] titer, negative diagnostic work-up, negative CT), HumaSPECT-Tc correctly identified disease in 15 of 22 (68%) patients. HumaSPECT-Tc images provided additional clinical data that would have affected patient management decisions in 40 of 202 (19.8%) patients. In 365 patients who received 88BV59, only a single detectable human anti-human antibody (HAHA) response (90 ng/mL) at 9 weeks postinfusion was observed. CONCLUSION: HumaSPECT-Tc can provide important and accurate information about the presence and location of disease in patients with a high clinical suspicion of metastatic or recurrent colorectal cancer and either positive (known disease) or negative (occult disease) CT scans

Radioimmunoscintigraphy of recurrent, metastatic, or occult colorectal cancer with technetium Tc 99m 88BV59H21-2V67-66 (HumaSPECT (R)-Tc), a totally human monoclonal antibody - Patient management benefit from a phase III multicenter study

PURPOSE: The study contained herein was undertaken to evaluate the accuracy of radiolabeled human monoclonal antibody, 88BV59H21-2V67-66 (88BV59 or HumaSPECT-Tc), in predicting disease resectability in presurgical subjects with recurrent, metastatic, or occult colorectal carcinoma. METHODS: A total of 219 patients with disease visualized on computed tomographic scan (recurrent or metastatic disease) or with negative or equivocal computed tomographic scan and rising carcinoembryonic antigen serum levels (occult group) received technetium Tc99m-labeled 88BV59 intravenously. Planar and single photon emission computed tomograhic images were obtained 14 to 20 hours postinfusion, before surgery. The ability of computed tomographic and HumaSPECT-Tc imaging to define the extent of disease and to predict resectability was evaluated based on surgical and histopathologic results. RESULTS: In patients with recurrent or metastatic disease (170 evaluable patients), the accuracy of predicting nonresectability of disease was significantly greater (P \u3c 0.001) for HumaSPECT-Tc than for computed tomography (60 vs 29 percent). Computed tomography understaged 41 percent of patients believed to have resectable disease compared with 27 percent for HumaSPECT-Tc (P \u3c 0.001). In occult disease patients (29 computed tomographic and 28 HumaSPECT-Tc evaluable patients), the overall accuracy of predicting resectability/nonresectability was 6 percent for HumaSPECT-Tc compared with 24 percent from computed tomography. Administration of HumaSPECT-Tc had no effect on monoclonal antibody-based in vitro diagnostic assays. Only a single patient demonstrated an anti-antibody response (90 ng/ml) at nine weeks postinfusion. CONCLUSION: HumaSPECT-Tc was more accurate than computed tomography in determining disease resectability in patients with metastatic, recurrent, or occult cancer. The addition of HumaSPECT-Tc imaging can play a significant role in patient management decisions