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: To investigate the role of the anti-cellular immune response in the protection of rhesus macaques against infection with the simian immunodeficiency virus SIVmac. To determine the biological differences between SIV challenge stocks grown either on human T-cell lines or on monkey peripheral blood mononuclear cells (MPBMC).', 'A protective SIVmac split vaccine was administered to rhesus macaques and their anti-, B- and T-cell response monitored. Vaccinees and controls were challenged with SIVmac grown either on human or on monkey cells. The in vivo replication rate of, and the immune response to, the two viruses was compared.', 'Five rhesus macaques were immunized with a total of 2 mg each of purified SIVmac251/32H grown on the human C8166 T-cell line. The antibody and proliferative T-cell responses were evaluated by enzyme-linked immunosorbent assay and T-cell proliferation assay, respectively. Four protected animals and four controls were reboosted and challenged with MPBMC-grown SIVmac251 (SIVmac251/MPBMC). Cell-free virus load was determined by titration of plasma for SIV infectivity on C8166 cells and antigen with a core antigen capture assay.', 'Protection from virus challenge with C8166-grown SIVmac251/32H or SIVmac251/MPBMC did not correlate with anti-cellular antibodies or proliferative T-cell reactivities. Control animals infected with SIVmac251/MPBMC showed high persistent antigenaemia and high plasma virus titres. Both were absent in controls infected with complement C8166-grown SIVmac251/32H. Whereas the latter always seroconverted against the full panel of viral polypeptides, SIVmac251/MPBMC-infected animals showed a drastically decreased antibody response.\Question: Does protection of monkeys by a split vaccine against SIVmac depend upon biological properties of the challenge virus?
[A]: Neither the antibody nor the proliferative T-cell response to SIVmac correlates with protection from virus challenge. In contrast to SIVmac251/32H grown on C8166 cells, the MPBMC-grown challenge virus SIVmac251 appears to belong to the 'rapid-high' phenotype, possibly explaining the lack of protection against this SIV.

[Q]: Context: To assess the effect of six different enteral diets on the gut barrier.', 'Laboratory study.', 'University hospital, Germany.', '70 Specific pathogen free female Crl:CDR BR rats.', 'For 7 days, 6 groups of rats were fed orally with standard chow (n = 15); total parenteral nutrition solution (oral TPN, n = 15); elemental diet (ED, n = 10); nutrient-defined diet (NDD, n = 10); or the NDD supplemented with uracil (NDD+uracil, n = 10), or fibre (NDD+fibre, n = 10).', 'Bacterial translocation to mesenteric lymph nodes, numbers of Gram negative enterobacteria and total aerobic bacteria in the caecum, and intestinal concentrations of secretory IgA.', 'The incidence of bacterial translocation was significantly increased in the groups given oral TPN, ED, NDD, and NDD+uracil compared with the group given chow. Only NDD+fibre resulted in a similar degree of translocation to that in the chow group. All groups in which there was increased translocation had a highly significant overgrowth of aerobic bacteria in the caecum, mainly by Gram negative enteric organisms. The secretory IgA concentration was reduced in the group that had been given oral TPN, and that in the ED and NDD+uracil groups was similar to that in the chow group. NDD and NDD+fibre were associated with higher intestinal concentrations of secretory IgA than chow.\Question: Is fibre an essential ingredient of enteral diets to limit bacterial translocation in rats?
[A]: Fibre-free enteral diets do not protect the gut antimicrobial barrier whatever else is in them. The superiority of early enteral as opposed to parenteral nutrition after injury may, therefore, not be the result of a specific protective effect on the gut barrier. The supplementation of commercial enteral diets with bulk fibre should be tested in clinical trials.

[Q]: Context: To examine the effect of a single spinal manipulation therapy (SMT) on the in vitro production of inflammatory cytokines, tumor necrosis factor alpha, and interleukin (IL) 1beta, in relation to the systemic (in vivo) levels of neurotransmitter substance P (SP).', 'Sixty-four asymptomatic subjects were assigned to SMT, sham manipulation, or venipuncture control group. SMT subjects received a single adjustment in the thoracic spine. Blood and serum samples were obtained from subjects before and then at 20 minutes and 2 hours after intervention. Whole-blood cultures were activated with lipopolysaccharide (LPS) for 24 hours. Cytokine production in culture supernatants and serum SP levels were assessed by specific immunoassays.', 'Over the study period, a significant proportion (P </= .05) of sham and control subjects demonstrated progressive increases in the synthesis of tumor necrosis factor alpha and IL-1beta. Conversely, in a comparable proportion of cultures from SMT-derived subjects, the production of both cytokines decreased gradually. Normalization of the observed alterations to reflect the changes relative to self-baselines demonstrated that, within 2 hours after intervention, the production of both cytokines increased significantly (P < .001 to .05) in both controls. In contrast, a significant (P < .001 to .05) reduction of proinflammatory cytokine secretion was observed in cultures from SMT-receiving subjects. In all study groups, serum levels of SP remained unaltered within 2 hours after intervention.\Question: Does spinal manipulative therapy reduce inflammatory cytokines but not substance P production in normal subjects?
[A]:
SMT-treated subjects show a time-dependent attenuation of LPS-induced production of the inflammatory cytokines unrelated to systemic levels of SP. This suggests SMT-related down-regulation of inflammatory-type responses via a central yet unknown mechanism.