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.

Input: Consider Input: Background: The Major Histocompatibility Complex (MHC) is a genomic region containing genes with crucial roles in immune responses. MHC class I and class II genes encode antigen-presenting molecules expressed on the cell surface. To counteract the high variability of pathogens, the MHC evolved into a region of considerable heterogeneity in its organization, number and extent of polymorphism. Studies of MHCs in different model species contribute to our understanding of mechanisms of immunity, diseases and their evolution. Camels are economically important domestic animals and interesting biomodels. Three species of Old World camels have been recognized: the dromedary (Camelus dromedarius), Bactrian camel (Camelus bactrianus) and the wild camel (Camelus ferus). Despite their importance, little is known about the MHC genomic region, its organization and diversity in camels. The objectives of this study were to identify, map and characterize the MHC region of Old World camelids, with special attention to genetic variation at selected class MHC II loci. Results: Physical mapping located the MHC region to the chromosome 20 in Camelus dromedarius. Cytogenetic and comparative analyses of whole genome sequences showed that the order of the three major sub-regions is "Centromere -Class II -Class III -Class I". DRA, DRB, DQA and DQB exon 2 sequences encoding the antigen binding site of the corresponding class II antigen presenting molecules showed high degree of sequence similarity and extensive allele sharing across the three species. Unexpectedly low extent of polymorphism with low numbers of alleles and haplotypes was observed in all species, despite different geographic origins of the camels analyzed. The DRA locus was found to be polymorphic, with three alleles shared by all three species. DRA and DQA sequences retrieved from ancient DNA samples of Camelus dromedarius suggested that additional polymorphism might exist. Conclusions: This study provided evidence that camels possess an MHC comparable to other mammalian species in terms of its genomic localization, organization and sequence similarity. We described ancient variation at the DRA locus, monomorphic in most species. The extent of molecular diversity of MHC class II genes seems to be substantially lower in Old World camels than in other mammalian species.

Output: The major histocompatibility complex in Old World camelids and low polymorphism of its class II genes

Input: Consider Input: Infectious bronchitis virus (IBV), the first coronavirus described, was initially associated with severe respiratory disease. However, outbreaks have more recently also been associated with nephropathogenesis. Topographically interrelated antigenic determinants of the nephropathogenic Gray strain of IBV were characterized using eleven monoclonal antibodies (MAbs). Four MAbs (IgG 2a~c) defined epitopes that were both conformation-independent and group specific, reacting with Gray, Arkansas (Ark), and Massachusetts41 (Mass41) strains. Seven MAbs (IgG 1~:) defined conformation-dependent epitopes that could differentiate the Gray from the Ark and Mass strains. The spike protein specificity of the MAbs was determined with the conformation-independent MAbs and one MAb that reacted only in "non-denaturing" western blot assays. Competitive binding studies using these MAbs suggested a high degree of functional dependency among the associated epitopes as might be expected with a protein of complex secondary and tertiary structure. At least two regions associated with complete protection of infected embryos were identified that consisted of both conformation-dependent and independent epitopes. However, a "non-neutralizing" MAb, which did not protect the embryo from gross lesions, did inhibit virus-induced lesions and replication in the kidneys. These MAbs should be valuable tools in studying IBV pathogenesis.

Output: Epitopes on the spike protein of a nephropathogenic strain of infectious bronchitis virus

Input: Consider Input: Porcine epidemic diarrhea virus (PEDV) Isobaric tags for relative and absolute quantitation (iTRAQ) Proteomics Pathway analysis The re-emerging porcine epidemic diarrhea virus (PEDV) variant related diarrhea has been documented in China since late 2010 and now with global distribution. Currently, a virulent PEDV CH/YNKM-8/2013 and a CV777 vaccine strain-like AH-M have been successfully isolated from the clinical samples. To dissect out the underlying pathogenic mechanism of virulent PEDV and clarify the differences between virulent and CV777 vaccine strainlike PEDV infections, we performed an iTRAQ-based comparative quantitative proteomic study of Vero cells infected with both PEDV strains. A total of 661 and 474 differentially expressed proteins were identified upon virulent and CV777 vaccine strain-like isolates infection, respectively. Ingenuity Pathway Analysis was employed to investigate the canonical pathways and functional networks involved in both PEDV infections. Comprehensive studies have revealed that the PEDV virulent strain suppressed protein synthesis of Vero cells through down-regulating mTOR as well as its downstream targets 4EBP1 and p70S6K activities, which were validated by immunoblotting. In addition, the virulent strain could activate NF-B pathway more intensively than the CV777 vaccine strain-like isolate, and elicit stronger inflammatory cascades as well. These data might provide new insights for elucidating the specific pathogenesis of PEDV infection, and pave the way for the development of effective therapeutic strategies. Biological significance: Porcine epidemic diarrhea is now worldwide distributed and causing huge economic losses to swine industry. The immunomodulation and pathogenesis between PEDV and host, as well as the difference between virulent and attenuated strains of PEDV infections are still largely unknown. In this study, we presented for the first application of proteomic analysis to compare whole cellular protein alterations induced by virulent and CV777 vaccine strain-like PEDV infections, which might contribute to understand the pathogenesis of PEDV and anti-viral strategy development.
Output: iTRAQ-based comparative proteomic analysis of Vero cells infected with virulent and CV777 vaccine strain-like strains of porcine epidemic diarrhea virus