Epistemic_Statements  

CORD-19:013ce450f63ae2496b92f987e35b55125a43947f JSONTXT 9 Projects

Annnotations TAB TSV DIC JSON TextAE

Id Subject Object Predicate Lexical cue
T1 439-642 Epistemic_statement denotes Thus stimulation of circUlating antibodies using either live oral or inactivated poliovirus vaccines can prevent the systemic spread of poliovirus to the central nervous system and the paralytic disease.
T2 970-1253 Epistemic_statement denotes Whether the problems encountered with oral administration of soluble protein antigens can be overcome by the use of improved mucosal adjuvants [muranyl dipeptide, immune stimulating complexes (ISCOMs), cholera or Escherichia coli enterotoxins, avridine, proteosomes, cytokines, etc.]
T3 1254-1455 Epistemic_statement denotes or new and novel delivery systems (liposomes, live recombinant vectors, microspheres, DNA plasmids, virus-like particles) requires further investigation, and specific examples are given in this review.
T4 2176-2313 Epistemic_statement denotes Enteropathogenic viruses belonging to at least five different families have been associated with diarrhea in pigs (Table I, Saif, 1990) .
T5 2314-2520 Epistemic_statement denotes Each of these viruses infects mainly the villous enterocytes of pigs and, with the possible exception of astroviruses (Saifet al., 1980) , induces villous atrophy and a malabsorptive diarrhea (Saif, 1990) .
T6 2725-2794 Epistemic_statement denotes A potential explanation for Bridger + 1980 Bridger + 1980 Saif et al.
T7 2912-3140 Epistemic_statement denotes The authors found that TGEV enters and exits from polarized epithelial cells in vitro via the apical surface; in contrast, another coronavirus, mouse hepatitis virus (MHV), enters the same cells apically but exits basolaterally.
T8 3141-3482 Epistemic_statement denotes The investigators speculated that similar differences in the mode of release of coronaviruses from infected host cells could contribute to the nature of the localized intestinal infections induced by TGEV (released apically into the gut lumen) or the systemic infections associated with MHV (released basolaterally into the blood and lymph).
T9 4328-4551 Epistemic_statement denotes In contrast, PRCV strains replicate in the upper and lower respiratory tract, with little or no replication in the intestine, and generally cause subclinical infections or mild respiratory disease (Pensaert and Cox, 1989) .
T10 5930-6164 Epistemic_statement denotes To date, commercial and experimental candidate vaccines have not been highly effective in preventing enteric viral infections and gastroenteritis in humans or animals (reviewed in Saif and Jackwood, 1990; Kapikian and Chanock, 1990) .
T11 6593-6792 Epistemic_statement denotes These results suggest that more research is needed to optimize enteric vaccines to induce local mucosal immune responses that more closely mimic ones elicited after exposure to the virulent organism.
T12 7631-7830 Epistemic_statement denotes These functions are in contrast to systemically induced IgG antibodies that mediate inflammatory reactions leading to the killing and elimination of pathogens, thereby maintaining systemic sterility.
T13 7831-8037 Epistemic_statement denotes Although in earlier studies SIgA was envisioned to act mainly at the luminal mucosal surfaces, recent data suggest that dimeric IgA may bind antigens on the basolateral side of intestinal epithelial cells .
T14 8038-8470 Epistemic_statement denotes These immune complexes would then be transported across the epithelial cell via the PIgR and secreted back into the intestinal lumen, thereby eliminating foreign antigens that have penetrated the epithelium, Other recent reports suggest that SIgA may function intracellularly in host defense by inhibiting viral replication or assembly in vitro (Armstrong and Dimmock, 1992; Marzanec et al., 1992) and in vivo (Burns et al., 1996) .
T15 9781-10023 Epistemic_statement denotes Among the first reports to document that antigenic stimulation at one mucosal site (intestine) leads to SIgA antibody responses at a distinct mucosal site (mammary gland) were the studies of lactogenic immunity to TGEV in swine by Bohl et al.
T16 10056-10377 Epistemic_statement denotes The discovery and subsequent confirmation (Weisz-Carrington et al., 1978) of the interrelationship between the SIgA system of the intestine and mammary gland was an important tenet of the common mucosal immune system, and this system was later confirmed in humans and other species (Mestecky, 1987; McGhee et al., 1992) .
T17 10610-10898 Epistemic_statement denotes Recent studies, including further studies of immunity to porcine coronaviruses (Van Cott et al., 1993 , 1994 Saif et al., 1994b; Saif, 1996) , have suggested that functional compartmentalization and limited reciprocity may exist within some components of the common mucosal immune system.
T18 11269-11476 Epistemic_statement denotes Such observations have important implications for the design of effective mucosal vaccines, but information on effective and practical procedures to induce protective immunity at mucosal surfaces is lacking.
T19 11726-11887 Epistemic_statement denotes To analyze the interrelationships between BALT and GALT related to protective immunity, we used as a model the three antigenically related porcine coronaviruses.
T20 12250-12355 Epistemic_statement denotes These questions were addressed: Is PRCV a more effective candidate vaccine for TGEV than attenuated TGEV?
T21 12533-12710 Epistemic_statement denotes What are the comparative IgA and IgG ASC responses induced in GALT and BALT and the level of protection after inoculation with PRCV, TGEV-A, or TGEV-V and challenge with TGEV-V?
T22 12711-12828 Epistemic_statement denotes In pigs recovered from infection with TGEV-V and reexposed to TGEV-V, what are the correlates of protective immunity?
T23 12829-13010 Epistemic_statement denotes We first investigated the comparative immune responses to live PRCV versus TGEV-V, the degree of protection induced against TGEV-V challenge, and potential correlates of protection.
T24 13822-14022 Epistemic_statement denotes The presence of high numbers of IgA-ASC in the gut lamina propria (LP) and high LPA responses in the MLN at challenge (PCD 0) was associated with 100% protection against diarrhea after TGEV challenge.
T25 14706-15096 Epistemic_statement denotes After TGEV challenge (PCD 4), the numbers of IgG-ASC and to a lesser extent IgA-ASC increased rapidly in the intestinal lamina propria of the PRCV-exposed pigs, suggesting that virus-specific IgG-ASC precursors derived in BALT or systemic lymphoid tissues of the PRCV-exposed pigs may migrate to the intestine in response to TGEV challenge and contribute to the partial protection observed.
T26 15380-15496 Epistemic_statement denotes Thus TGEV infections or vaccines that induce immunity via GALT and secondarily via BALT may prevent PRCV infections.
T27 15497-15681 Epistemic_statement denotes Whether the more frequent use of live attenuated TGEV vaccines in the United States (which induce IgG ASC in BLN, Table IV ) compared to Europe has had an impact on limiting the et al.
T28 16119-16286 Epistemic_statement denotes spread of PRCV infections in the United States is unknown, but at present PRCV infections appear to be less widespread among swine in the United States than in Europe.
T29 16757-17036 Epistemic_statement denotes Further studies on the induction and immune regulation of responses to TGEV and PRCV that affect the distribution of ASC and T lymphocytes should provide important insights to optimize oral vaccine regimens to elicit protective mucosal immune responses against enteric pathogens.
T30 18435-18538 Epistemic_statement denotes Such factors presumably contribute to the corresponding lack of efficacy of TGEV vaccines in the field.
T31 19978-20574 Epistemic_statement denotes Studies of immune responses of rabbits inoculated with purified LT-B/SD fusion products expressed from Salmonella or the recombinant Salmonella revealed that neutralizing antibodies to TGEV were induced by the purified LT-B/S D and TGEV antibodies were elicited in serum and intestinal secretions after oral inoculation with the recombinant Salmonella.Thus, if similar TGEV neutralizing IgA antibody responses can be induced in the intestines of pigs by the recombinant bacterial vaccines, such vaccines warrant further study to access their ability to induce protective immunity to TGEV in pigs.
T32 22037-22219 Epistemic_statement denotes The transient appearance of IgA ASC in the blood mirrored the IgA ASC responses in the gut and could serve as an indicator for IgA ASC intestinal responses after rotavirus infection.
T33 22405-22677 Epistemic_statement denotes Interestingly pigs inoculated IM or perorally (PO) with inactivated rotavirus in IFA had a very high number of IgG ASCs in PBL, but few IgG or IgA ASCs in the intestinal lamina propria and, like pigs given inactivated virus PO, minimal protection (0-17%) against diarrhea.
T34 22799-22972 Epistemic_statement denotes and level of the ASC response and, similar to the results of the TGEV studies, the degree of protection was correlated with the numbers of IgA ASCs induced in the intestine.
T35 22973-23171 Epistemic_statement denotes Similarly, in studies of natural rotavirus infections in children, higher fecal IgA antibody titers to rotavirus were associated with protection against infection and illness (Matson et al., 1993) .
T36 23172-23382 Epistemic_statement denotes Mouse studies of rotavirus-induced infection revealed similar findings: induction of intestinal IgA antibody responses were positively associated with protection against rotavirus shedding (Feng et al., 1994) .
T37 23383-23653 Epistemic_statement denotes Although not yet evaluated in swine, a new strategy for rotavirus vaccines is the creation of recombinant virus-like particles (VLPs) produced by the coexpression of the four rotavirus capsid genes (VP2/4/6/7) in a baculovirus expression system (Crawford et al., 1994) .
T38 24220-24323 Epistemic_statement denotes Thus VLP vaccines show promise as novel vaccines designed to induce mucosal immunity against rotavirus.
T39 24324-24491 Epistemic_statement denotes Further research is needed to identify the optimal delivery systems and mucosal adjuvants for use with the VLP vaccines to most effectively stimulate mucosal immunity.