instruction:
In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
question:
Coronavirus reverse genetic systems have become valuable tools for studying the molecular biology of coronavirus infections. They have been applied to the generation of recombinant coronaviruses, selectable replicon RNAs, and coronavirus-based vectors for heterologous gene expression. Here we provide a collection of protocols for the generation, cloning, and modification of full-length coronavirus cDNA using vaccinia virus as a cloning vector. Based on cloned coronaviral cDNA, we describe the generation of recombinant coronaviruses and stable cell lines containing coronaviral replicon RNAs. Initially, the vaccinia virus-based reverse genetic system was established for the generation of recombinant human coronavirus 229E. However, it is also applicable to the generation of other coronaviruses, such as the avian infectious bronchitis virus, mouse hepatitis virus, and SARS coronavirus.
answer:
Generation of Recombinant Coronaviruses Using Vaccinia Virus as the Cloning Vector and Stable Cell Lines Containing Coronaviral Replicon RNAs


question:
One sentence summary: CmpA is an OmpA-like protein in Legionella pneumophila that is required for efficient intracellular replication in both primary macrophages and in the environmental host Acanthamoeba castellanii. Editor: Akio Nakane The OmpA-like protein domain has been associated with peptidoglycan-binding proteins, and is often found in virulence factors of bacterial pathogens. The intracellular pathogen Legionella pneumophila encodes for six proteins that contain the OmpA-like domain, among them the highly conserved uncharacterized protein we named CmpA. Here we set out to characterize the CmpA protein and determine its contribution to intracellular survival of L. pneumophila. Secondary structure analysis suggests that CmpA is an inner membrane protein with a peptidoglycan-binding domain at the C-teminus. A cmpA mutant was able to replicate normally in broth, but failed to compete with an isogenic wild-type strain in an intracellular growth competition assay. The cmpA mutant also displayed significant intracellular growth defects in both the protozoan host Acanthamoeba castellanii and in primary bone marrow-derived macrophages, where uptake into the cells was also impaired. The cmpA phenotypes were completely restored upon expression of CmpA in trans. The data presented here establish CmpA as a novel virulence factor of L. pneumophila that is required for efficient intracellular replication in both mammalian and protozoan hosts.
answer:
A conserved OmpA-like protein in Legionella pneumophila required for efficient intracellular replication


question:
The immunostimulatory effects of oligodeoxyribonucleotides (ODN) containing unmethylated CpG dinucleotides (CpG-ODN) in certain base contexts have been extensively studied in man and mice. One major action is their ability to trigger production of massive amounts of interferon-a (IFN-a) by plasmacytoid dendritic cells (PDC), also referred to as natural IFN-a/b producing cells (NIPC). The present study using porcine PBMC activated by CpG-ODN or plasmid DNA revealed a considerable variation in the IFN-a production in response to various CpG-ODN constructs. Several phosphodiester ODNs, such as 5 0 TTTTCAATTCGAAGATGAAT 3 0 (ODN H), and the plasmid pcDNA3 all required pre-incubation with lipofectin in order to induce IFN-a. Intact unmethylated CpGs were also important, because methylation or substitution of the cytosines and CpG-inversion strongly reduced the IFN-a induction by single-or double-stranded forms of ODN H. Certain CpG-ODNs that contained flanking phosphorothioate or phosphodiester poly-G sequences were potent inducers of IFN-a without pre-incubation with lipofectin, for instance the ODN 2216 (5 0 GGGGGACGATCGTCGGGGGG 3 0 ). While poly-G sequences have been suggested to increase uptake of ODNs by cells, they did not obviate the need for lipofectin when added to the ODN H. However, they resulted in up to five-fold increases of the IFN-a levels caused by ODN H upon lipofection, indicating other enhancing effects of poly-G sequences on the induction of IFN-a. The identity of the IFN-a producing cells (IPC) stimulated by CpG-ODN or plasmid DNA was studied by means of flow cytometry using combined staining for intracellular IFN-a and surface markers. Approximately 1-3 IPC/10 3 PBMC were detected, compared to only 3 IPC/10 4 PBMC stimulated by Aujeszky's disease virus. The IPC frequencies were confirmed by detection of IFN-a mRNA positive cells by in situ hybridisation. The IPC induced by CpG-ODN or plasmid DNA had a similar phenotype, expressing CD2 and CD4 and intermediate levels of MHC class II and the myeloid marker SWC3, but not the markers of T and B cells or
answer:

Characteristics of oligodeoxyribonucleotides that induce interferon (IFN)-a in the pig and the phenotype of the IFN-a producing cells monocytes (CD3, CD21 and CD14)