Genomic Epidemiology as a Public Health Tool to Combat Mosquito-Borne Virus Outbreaks.

Next-generation sequencing technologies, exponential increases in the availability of virus genomic data, and ongoing advances in phylogenomic methods have made genomic epidemiology an increasingly powerful tool for public health response to a range of mosquito-borne virus outbreaks. In this review, we offer a brief primer on the scope and methods of phylogenomic analyses that can answer key epidemiological questions during mosquito-borne virus public health emergencies. We then focus on case examples of outbreaks, including those caused by dengue, Zika, yellow fever, West Nile, and chikungunya viruses, to demonstrate the utility of genomic epidemiology to support the prevention and control of mosquito-borne virus threats. We extend these case studies with operational perspectives on how to best incorporate genomic epidemiology into structured surveillance and response programs for mosquito-borne virus control. Many tools for genomic epidemiology already exist, but so do technical and nontechnical challenges to advancing their use. Frameworks to support the rapid sharing of multidimensional data and increased cross-sector partnerships, networks, and collaborations can support advancement on all scales, from research and development to implementation by public health agencies.

Differential extraction of tumor-specific transplantation antigen and embryonic antigen from simian virus 40- and adenovirus 7-induced sarcoma cells of hamsters with 1-butanol and 3 M potassium chloride.

Simian virus 40 (SV40)-induced sarcomas and adenovirus 7-induced sarcomas (Adv-7) exhibit both specific tumor-specific transplantation antigens (TSTA) and cross-protective embryonic antigens at the cell surface in the LAK:LVG(SYR) strain of Syrian golden hamsters. Specific SV40 TSTA could be released from the surfaces of living hamster sarcoma cells in a 2.5% crude 1-butanol extract (CBE) and served as immunogen to protect syngeneic recipients against subsequent homologous but not heterologous tumor cell challenge. The CBE-extracted SV40-induced TSTA (tumor-specific) was observed to be free of detectable, cross-protective embryonic antigens (EA) by tumor transplantation assays. The induction of cytotoxic lymphocyte-mediated immunity with the CBE-released TSTA was dependent on the administration of a single sensitizing injection of 12-20 micrograms antigen protein. Higher concentrations (50-1,000 micrograms) of the CBE tumor cell extract, given in a single injection, enhanced tumor growth as did two injections of 12.5 micrograms CBE-extracted SV40-induced TSTA at 1-week intervals. A cross-protective antigen(s), not detected in the CBE tumor extracts, was retained in the intact, 1-butanol-extracted SV40 and Adv-7-induced tumor cell lines after completion of the CBE extraction procedure and in similarly extracted 10-day hamster fetal cells. Some alterations in the normal immunogenicity of EA extracted with CBE followed by KCI from SV40-induced sarcoma cells could be detected in the transplantation assays and lymphocyte transformation assays, whereas EA extracted from CBE-KCI-treated Adv-7 cells or 10-day hamster fetal cells retained normal immunogenicity in vivo and in vitro. These procedures provide a means for successful separation of immunogenic SV40- and Adv-7-induced TSTA from detectable, biologically active, cross-protective EA from the surfaces of these sarcoma cells.

The major APN transcript of the alveolar type II epithelial cell originates from a unique upstream promoter region.

Aminopeptidase N (APN, EC 3.4.11.2) is an ectopeptidase expressed in lung at the apical surface of alveolar type II epithelial cells. Its expression is upregulated during fetal lung development. To begin to understand the regulation of APN expression during lung development, we used the rapid modification of cDNA ends (RACE) to clone the 5' end of the major APN transcript in rat lung and alveolar type II cells. The cloned sequence revealed a unique 135 bp untranslated exon which genomic cloning and restriction mapping indicated was located more than 14 kb upstream from the coding sequence. A 172 bp genomic fragment flanking the untranslated exon produced a high level of expression of a reporter gene in transient transfection assays using a human lung adenocarcinoma cell line. The DNA fragment includes elements known to be important for expression of lung specific proteins, including the surfactant-associated proteins A, B, and C and the Clara cell specific protein. Comparison of the APN genomic sequences and gene structure from human and rat suggests that the exon present in the rat lung transcript may result from the use of a previously uncharacterized APN promoter.

Decreased eIF3e/Int6 expression causes epithelial-to-mesenchymal transition in breast epithelial cells.

eIF3e/Int6 is a component of the multi-subunit eIF3 complex, which binds directly to the 40S ribosome to facilitate ribosome recruitment to mRNA and hence protein synthesis. Reduced expression of eIF3e/Int6 has been found in up to 37% of human breast cancers, and expression of a truncated mutant version of the mouse eIF3e/Int6 protein leads to malignant transformation of normal mammary cells. These findings suggest that eIF3e/Int6 is a tumor suppressor; however, a recent study has reported that a reduction of eIF3e/Int6 expression in breast cancer cells leads to reduced translation of oncogenes, suggesting that eIF3e/Int6 may in fact have an oncogenic role in breast cancer. To gain a better understanding of the role of eIF3e/Int6 in breast cancer, we have examined the effects of decreased eIF3e/Int6 expression in an immortalized breast epithelial cell line, MCF-10A. Surprisingly, we find that decreased expression of eIF3e/Int6 causes breast epithelial cells to undergo epithelial-to-mesenchymal transition (EMT). We show that EMT induced by a decrease in eIF3e/Int6 expression imparts invasive and migratory properties to breast epithelial cells, suggesting that regulation of EMT by eIF3e/Int6 may have an important role in breast cancer metastasis. Furthermore, we show that reduced eIF3e/Int6 expression in breast epithelial cells causes a specific increase in the expression of the key EMT regulators Snail1 and Zeb2, which occurs at both the transcriptional and post-transcriptional levels. Together, our data indicate a novel role of eIF3e/Int6 in the regulation of EMT in breast epithelial cells and support a tumor suppressor role of eIF3e/Int6.