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.

Q: Basic and translational research on lung biology has discovered multiple progenitor cell types, specialized or facultative, responsible for turnover, renewal, and repair. Isolation of populations of resident lung progenitor cells (LPCs) has been described by multiple protocols, and some have been successfully applied to healthy human lung tissue. We aimed at understanding how different cell culture conditions may affect, in vitro, the phenotype of LPCs to create an ideal niche-like microenvironment. The influence of different substrates (i.e., fibronectin, gelatin, laminin) and the impact of a three-dimensional/two-dimensional (3D/2D) culture switch on the biology of LPCs isolated as lung spheroids (LSs) from normal adult human lung biopsy specimens were investigated. We applied a spheroid culture system as the selective/inductive step for progenitor cell culture, as described in many biological systems. The data showed a niche-like proepithelial microenvironment inside the LS, highly sensitive to the 3D culture system and significantly affecting the phenotype of adult LPCs more than culture substrate. LSs favor epithelial phenotypes and LPC maintenance and contain cells more responsive to specific commitment stimuli than 2D monolayer cultures, while secreting a distinctive set of paracrine factors. We have shown for the first time, to our knowledge, how culture as 3D LSs can affect LPC epithelial phenotype and produce strong paracrine signals with a distinctive secretomic profile compared with 2D monolayer conditions. These findings suggest novel approaches to maintain ex vivo LPCs for basic and translational studies. STEM CELLS TRANSLATIONAL MEDICINE 2016;5:1-11 SIGNIFICANCE A lung niche-like microenvironment was created ex vivo inside the pneumosphere. Pneumospheres have a distinctive secretomic profile compared with two-dimensional culture. Three-dimensional culture switch significantly affects lung progenitor phenotype. Lung progenitors in pneumospheres were more committed toward epithelial lineages.

A: Tissue-Specific Progenitor and Stem Cells Human Lung Spheroids as In Vitro Niches of Lung Progenitor Cells With Distinctive Paracrine and Plasticity Properties
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Q: Several polypeptide products of MHV-A59 ORF 1 a were characterized in MHV-A59 infected DBT cells, using antisera directed against fusion proteins encoded in the first 6.5 kb of ORFla. These included the previously identified N-terminal ORF 1 a product, ~28, as well as 290-, 240-, and 50-kDa polypeptides. P28 was always detected as a discrete band without larger precursors, suggesting rapid cleavage of p28 immediately after its synthesis. Once p28 was cleaved there was little degradation of the protein over a 2-hr period. The intracellular cleavage of p28 was not inhibited by the protease inhibitor leupeptin, in contrast to results obtained during in vitro translation of genome RNA (Denison and Perlman, 1986). These data suggest that different protease activities may be responsible for the cleavage of p28 in vitro and in Go. The 290-kDa protein was an intermediate cleavage product derived from a precursor of greater than 400 kDa. The 290-kDa product was subsequently cleaved into secondary products of 50 and 240 kDa. The intracellular cleavage of the 290-kDa polypeptide was inhibited by leupeptin at concentrations which did not inhibit the early cleavage of p28 or the cleavage of the 290-kDa product from its larger polyprotein precursor. In the presence of zinc chloride, a product of >320 kDa was detected, which appears to incorporate p28 at its amino terminus. This suggests that at least two protease activities may be necessary for processing of ORFl a proteins, one of which cleaves p28 and is sensitive to zinc chloride but resistant to leupeptin, and the other which cleaves the 290-kDa precursor and is sensitive to both inhibitors. Both the 290-and 240-kDa proteins should contain sequences predicted to encode two papain-like prOtesS? activities. 0 1992 Academic PVE.S. Inc.

A: Intracellular Processing of the N-Terminal ORF la Proteins of the Coronavirus MHV-A59 Requires Multiple Proteolytic Events
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Q: Background: Patterns of genetic and genomic variance are informative in inferring population history for human, model species and endangered populations. Results: Here the genome sequence of wild-born African cheetahs reveals extreme genomic depletion in SNV incidence, SNV density, SNVs of coding genes, MHC class I and II genes, and mitochondrial DNA SNVs. Cheetah genomes are on average 95 % homozygous compared to the genomes of the outbred domestic cat (24.08 % homozygous), Virunga Mountain Gorilla (78.12 %), inbred Abyssinian cat (62.63 %), Tasmanian devil, domestic dog and other mammalian species. Demographic estimators impute two ancestral population bottlenecks: one >100,000 years ago coincident with cheetah migrations out of the Americas and into Eurasia and Africa, and a second 11,084-12,589 years ago in Africa coincident with late Pleistocene large mammal extinctions. MHC class I gene loss and dramatic reduction in functional diversity of MHC genes would explain why cheetahs ablate skin graft rejection among unrelated individuals. Significant excess of non-synonymous mutations in AKAP4 (p < 0.02), a gene mediating spermatozoon development, indicates cheetah fixation of five function-damaging amino acid variants distinct from AKAP4 homologues of other Felidae or mammals; AKAP4 dysfunction may cause the cheetah's extremely high (>80 %) pleiomorphic sperm. The study provides an unprecedented genomic perspective for the rare cheetah, with potential relevance to the species' natural history, physiological adaptations and unique reproductive disposition. The African cheetah-the world's fastest land animalis a paradigm of physical prowess that displays numerous physiological adaptations allowing for magnificent high-speed sprints across the African plains. Cheetahs

A:
Genomic legacy of the African cheetah, Acinonyx jubatus Genomic legacy of the African cheetah, Acinonyx jubatus
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