In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

[Q]: Context: High arginase-1 (Arg) expression by myeloid-derived suppressor cells (MDSC) is known to inhibit antitumor T-cell responses through depletion of l-arginine. We have previously shown that nitric oxide (NO), an immune mediator produced from l-arginine, is a potent radiosensitizer of hypoxic tumor cells. This study therefore examines whether Arg(+) overexpressing MDSC may confer radioresistance through depleting the substrate for NO synthesis.', 'MDSC and Arg expression were studied in preclinical mouse CT26 and 4T1 tumor models and further validated in rectal cancer patients in comparison with healthy donors. The radioprotective effect of MDSC was analyzed in hypoxic tumor cells with regard to l-arginine depletion.', 'In both mouse tumors and cancer patients, MDSC expansion was associated with Arg activation causing accelerated l-arginine consumption. l-Arginine depletion in turn profoundly suppressed the capacity of classically activated macrophages to synthesize NO resulting in impaired tumor cell radiosensitivity. In advanced cT3-4 rectal cancer, circulating neutrophils revealed Arg overexpression approaching that in MDSC, therefore mounting a protumor compartment wherein Arg(+) neutrophils increased from 17% to over 90%.\Question: Do myeloid-derived suppressor cells reveal radioprotective properties through arginase-induced l-arginine depletion?
[A]: Protumor Arg(+) MDSC reveal a unique ability to radioprotect tumor cells through l-arginine depletion, a common mechanism behind both T-cell and macrophage inhibition.


[Q]: Context: The expression of growth-associated protein 43 (GAP-43), a marker of axonal growth, in the dorsal root ganglion (DRG) neurons innervating the lumbar intervertebral disc was assessed using the retrograde tracing method and immunohistochemistry.', 'To study whether disc inflammation affects GAP-43 expression in DRG neurons innervating the disc in rats.', 'Persistent inflammation and nerve ingrowth into the inner layer of degenerated discs can be a cause of discogenic pain. Although the presence of GAP-43-expressing nerve fibers in painful discs has been reported, the expression of GAP-43 in DRG neurons innervating the disc has not been studied.', "Seven days after the application of Fluoro-Gold to the L5-L6 disc, 50 microL of saline (n = 10, control group) or complete Freund's adjuvant (n = 10, inflammatory group) was applied to the disc in rats. Ten days after the Fluoro-Gold application, T13-L5 DRGs were double-stained with GAP-43 and either calcitonin gene-related peptide or isolectin B4 (IB4).", 'The percentage of Fluoro-Gold-labeled neurons that were positive for GAP-43 was significantly higher in the inflammatory group (44%) than in the control group (24%, P < 0.001). In both groups, the majority of GAP-43-positive neurons were small and positive for calcitonin gene-related peptide but not IB4.\Question: Does disc inflammation potentially promote axonal regeneration of dorsal root ganglion neurons innervating lumbar intervertebral disc in rats?
[A]: The present results suggest that disc inflammation potentially promotes axonal growth of DRG neurons innervating the disc. In light of the strong correlation between the expression of calcitonin gene-related peptide and nerve growth factor receptor, it is most likely that nerve growth factor-sensitive DRG neurons extend their axons following disc inflammation.


[Q]: Context: The most important factor for the selection of an umbilical cord blood unit (CBU) for hematopoietic stem cell transplantation is the total nucleated cell (TNC) count as a surrogate marker for stem cell content in the CBU. At present, about one in five donors can provide a CBU with a sufficient TNC count for umbilical cord blood (UCB) banking. It is labor-intensive to obtain consent of all eligible donors and optimization of the selection is needed. The purpose of this study was to investigate prenatal clinical predictors for TNC count that would help to identify successful UCB donors already on admission to the delivery unit.', 'This study was a retrospective analysis of 758 cryopreserved CBUs, collected from 2002 to 2006. Maternal and fetal factors analyzed were maternal age, gravidity, parity, weight, height, diabetes, premature rupture of membranes, gestational age, fetal sex, and birthweight. The impact on a high TNC count (<150 × 10(7) vs. ≥ 150 × 10(7)) of the CBU was modeled in a multivariate analysis model.', 'Fetal birthweight was the strongest predictor (p < 0.001) of TNC count of at least 150 × 10(7). With a composite score of parity, gestational week, maternal weight and height, fetal sex, and birthweight, a nomogram was developed that increased banking rates from 22.7% to 31.9% while decreasing the number of banked CBUs from 149 to 79.\Question: Does a prenatal prediction model for total nucleated cell count increase the efficacy of umbilical cord blood banking?
[A]:
Our prenatal prediction model increases the efficacy of obtaining informed consent for UCB banking while still allowing relevant numbers of CBUs to be banked.