Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

[Q]: Context: Surfactant protein (SP) D shares target cells with the proinflammatory cytokine TNF-alpha, an important autocrine stimulator of dendritic cells and macrophages in the airways.', 'We sought to study the mechanisms by which TNF-alpha and SP-D can affect cellular components of the pulmonary innate immune system.', 'Cytokine and SP-D protein and mRNA expression was assessed by means of ELISA, Western blotting, and real-time PCR, respectively, by using in vivo models of allergic airway sensitization. Macrophage and dendritic cell phenotypes were analyzed by means of FACS analysis. Maturation of bone marrow-derived dendritic cells was investigated in vitro.', 'TNF-alpha, elicited either by allergen exposure or pulmonary overexpression, induced SP-D, IL-13, and mononuclear cell influx in the lung. Recombinant IL-13 by itself was also capable of enhancing SP-D in vivo and in vitro, and the SP-D response to allergen challenge was impaired in IL-13-deficient mice. Allergen-induced increase of SP-D in the airways coincided with resolution of TNF-alpha release and cell influx. SP-D-deficient mice had constitutively high numbers of alveolar mononuclear cells expressing TNF-alpha, MHC class II, CD86, and CD11b, characteristics of proinflammatory, myeloid dendritic cells. Recombinant SP-D significantly suppressed all of these molecules in bone marrow-derived dendritic cell cultures.
Answer: TNF-alpha can contribute to enhanced SP-D production in the lung indirectly through inducing IL-13. SP-D, on the other hand, can antagonize the proinflammatory effects of TNF-alpha on macrophages and dendritic cells, at least partly, by inhibiting production of this cytokine.
[A]: Does surfactant protein D inhibit TNF-alpha production by macrophages and dendritic cells in mice?


[Q]: Context: Rapa Nui (Easter Island), located in the easternmost corner of the Polynesian Triangle, is one of the most isolated locations on the planet inhabited by humans. Archaeological and genetic evidence suggests that the island was first colonized by Polynesians around AD 1200, during their eastward expansion. Although it remains contentious whether Polynesians reached South America, suggestive evidence has been brought forward supporting the possibility of Native American contact prior to the European "discovery" of the island in AD 1722.', 'We generated genome-wide data for 27 Rapanui. We found a mostly Polynesian ancestry among Rapanui and detected genome-wide patterns consistent with Native American and European admixture. By considering the distribution of local ancestry tracts of eight unrelated Rapanui, we found statistical support for Native American admixture dating to AD 1280-1495 and European admixture dating to AD 1850-1895.
Answer: These genetic results can be explained by one or more pre-European trans-Pacific contacts.
[A]: Do genome-wide ancestry patterns in Rapanui suggest pre-European admixture with Native Americans?


[Q]: Context: The antileukemic drug asparaginase, a key component in the treatment of acute lymphoblastic leukemia, acts by depleting asparagine from the blood. However, little is known about its pharmacokinetics and mechanisms of therapy resistance are poorly understood. Here, we explored the in vivo biodistribution of radiolabeled asparaginase, using a combination of in vivo imaging and biochemical techniques, and provide evidence for tissue specific clearance mechanisms, which could reduce effectiveness of the drug at these specific sites.', 'In vivo localization of Indium-111-labeled E.coli asparaginase was carried out in C57Bl/6 mice by both microSPECT/CT and by ex vivo biodistribution studies. Mice were treated with liposomal clodronate to investigate the effect of macrophage depletion on tracer localization and drug clearance in vivo. Moreover, macrophage cell line models RAW264.7 and THP-1, as well as cathepsin B deficient mice, were used to identify the cellular and molecular components controlling asparaginase pharmacokinetics.', 'In vivo imaging and biodistribution studies showed a rapid accumulation of asparaginase in macrophage-rich tissues such as liver, spleen and in particular bone marrow. Clodronate-mediated depletion of phagocytic cells markedly prolonged the serum half-life of asparaginase in vivo and decreased drug uptake in target organs. Immunohistochemistry and in vitro binding assays confirmed the involvement of macrophage-like cells in the uptake of asparaginase. We identified the activity of the lysosomal protease cathepsin B in macrophages as a rate-limiting factor in degrading asparaginase both in vitro and in vivo.
Answer: We show that asparaginase is rapidly cleared from the serum by liver, spleen and bone marrow-resident phagocytic cells. As a consequence of this efficient uptake and protease mediated degradation, particularly bone marrow resident macrophages may provide a protective niche to leukemic cells.
[A]:
Does in vivo imaging of antileukemic drug asparaginase reveal a rapid macrophage mediated clearance from the bone marrow?