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In vivo potency testing of inactivated poliovirus vaccines (IPV) is generally performed in rats, although no systematic investigation has identified the most appropriate rat strain for anti-poliovirus antibody quantification. We investigated humoral immune responses to IPV in five different rat strains to identify the most suitable strain. Three outbred (Wistar, Wistar Hannover, Sprague-Dawley) and two inbred rat strains (Fisher 344, Wistar Furth) were immunized intramuscularly with a full or one-fifth human dose of commercial IPV. Anti-poliovirus neutralizing antibody (NA) titers were measured using Salk and Sabin virus neutralizing assays. Post-vaccination responses varied between strains; inbred strains showed greater animal-to-animal variation in NA responses than outbred strains. Virus NA titers persisted for 9 weeks with little reduction in the response. The outbred Wistar rat model was identified as the preferred strain for IPV potency testing based on its capacity to produce high, dose-dependent anti-poliovirus NA responses, with low animal-to-animal variation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Heart valve tissue engineering based on decellularized xenogenic or allogenic starter matrices has shown promising first clinical results. However, the availability of healthy homologous donor valves is limited and xenogenic materials are associated with infectious and immunologic risks. To address such limitations, biodegradable synthetic materials have been successfully used for the creation of living autologous tissue-engineered heart valves (TEHVs) in vitro. Since these classical tissue engineering technologies necessitate substantial infrastructure and logistics, we recently introduced decellularized TEHVs (dTEHVs), based on biodegradable synthetic materials and vascular-derived cells, and successfully created a potential off-the-shelf starter matrix for guided tissue regeneration. Here, we investigate the host repopulation capacity of such dTEHVs in a non-human primate model with up to 8 weeks follow-up. After minimally invasive delivery into the orthotopic pulmonary position, dTEHVs revealed mobile and thin leaflets after 8 weeks of follow-up. Furthermore, mild-moderate valvular insufficiency and relative leaflet shortening were detected. However, in comparison to the decellularized human native heart valve control - representing currently used homografts - dTEHVs showed remarkable rapid cellular repopulation. Given this substantial in situ remodeling capacity, these results suggest that human cell-derived bioengineered decellularized materials represent a promising and clinically relevant starter matrix for heart valve tissue engineering. These biomaterials may ultimately overcome the limitations of currently used valve replacements by providing homologous, non-immunogenic, off-the-shelf replacement constructs., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The objective of this experiment was to test the hypothesis that early environmental influences could affect cardiovascular reactivity to acute stress in borderline hypertensive rats. This study utilized a cross-fostering paradigm in which borderline hypertensive rat (BHR) pups were reared by their natural spontaneously hypertensive rat (SHR) mothers, by an adoptive SHR dam, or by an adoptive Wistar-Kyoto female. Several maternal behavior measures were taken throughout weaning. Cardiovascular responses to acute stress were measured in adult BHR offspring. SHR dams spent significantly more time engaged in arched, as contrasted with passive, nursing behaviors throughout the preweaning period. Although strain of dam had no effect on resting blood pressure or heart rate, BHR reared by WKY dams had a greatly reduced blood pressure response to acute stress compared with BHR raised by either natural or adoptive SHR dams. These results suggest that the expression of cardiovascular characteristics in the BHR can be modified by early environmental influences and support the hypothesis that the expression of the hypertensive phenotype in the BHR is dependent upon information that is conveyed both genetically and environmentally.

In the present study we characterize the stress response induced by copper in the fathead minnow, Pimephales promelas. The fathead minnow epithelial cell line ATCC CCL 42 was used to examine the induced synthesis and subcellular localization of the two major stress proteins, stress 70 and cpn60. Western blot analysis demonstrated increased stress70 in cells exposed to 400 and 500 microM Cu. Two-dimensional analysis revealed three isoforms of stress70, one of 70 kDa and two of 72 kDa, at the highest Cu concentration. Chaperonin60 abundance did not change over the same range of Cu concentrations. Indirect immunofluorescence microscopy revealed that stress70 localized in the cytoplasm, particularly in the paranuclear region. Chaperonin60 was localized in mitochondria. Further, when we examined the stress response elicited by Cu in fathead minnow larvae in vivo, we found that Cu induced the stress response at nominal Cu concentrations that were more than an order of magnitude lower that in the cell culture. This disparity between the concentration of Cu, which induced the stress response in cells in culture and in vivo, may be the result of differences in Cu complexation that alter its availability, uptake and toxicity.

A major component of the cellular stress response entails the induced synthesis of a suite of stress proteins under environmentally adverse conditions that functions to protect organisms from environmentally induced damage. Here, we examined induction of the stress response in the embryos of the sea urchin Strongylocentrus purpuratus under a combination of environmentally realistic conditions. First, we examined the response elicited over a range of free cupric ion activities, (Cu2+), using a metal buffer system to control trace metal speciation. We observed no pronounced differences in translational patterns in embryos exposed to free cupric ion activities, (Cu2+), of 10(-13)-10(-9) M by metabolic labeling, 1-dimensional electrophoresis and autoradiography. Further separation by 2-dimensional electrophoresis, however, revealed electrophoretically discernable variants of several groups of proteins at the higher Cu concentrations and the synthesis of a 60 kDa protein at (Cu2+) of 10(-9) M. In addition, there were differences in the stress response induced by heat-shock treatment in embryos cultured in seawater with different Cu concentrations; radiolabel was incorporated into a greater number of cellular proteins in embryos at lower (Cu2+) and the induced synthesis of stress proteins was greater. These data suggest that elevations in (Cu2+) impair the ability of the embryos to mount the stress response upon exposure to elevated temperatures and that Cu may alter critical developmental pathways by inhibiting the synthesis of regulatory proteins. Such effects on gene expression can result in manifestations that have been widely attributed to Cu toxicity, including developmental abnormalities and increased sensitivity to environmental extremes. We suggest that the particular sensitivity of embryonic systems upon exposure to multiple stressors may be a consequence of these mechanisms.

The present study tested the hypothesis that lesions of the central nucleus of the amygdala (CeA) would reduce the cardiovascular responses to acute stress in a rodent model that is genetically predisposed toward hypertension. Male borderline hypertensive rats (BHR) were given bilateral electrolytic lesions directed to destroy the CeA or were subjected to a sham procedure. Direct measurements of blood pressure and heart rate were recorded during rest, during 10 min of acute stress, and for 10 min following stress. Analysis of the data revealed that BHR with CeA lesions had a significant attenuation of the stress-induced pressor response compared to sham-operated subjects. Behavioral measures taken in an open field chamber before and after lesions revealed no differences in numbers of squares crossed or rearings. These results suggest that the CeA is an important neural structure in mediating cardiovascular responses to acute stress in a model susceptible to environmentally induced hypertension.

A number of previous studies have demonstrated that some aspect of baroreflex function is altered as hypertension develops. However, no studies have determined whether a chronic stressor can alter baroreflex function in the resting state. In the present study, male borderline hypertensive rats (BHR) were divided into three groups: control, stressed daily for 5 weeks, and stressed daily for 11 weeks. At the appropriate time, 7 different dosages of angiotensin II (AII) were given intravenously as a bolus injection. Heart rate (interbeat interval, or IBI) and mean arterial pressure were tracked for 90 subsequent beats. For each group, intercorrelations between pressure and IBI were obtained. In addition, overall means of pressure and IBI for each dosage were computed for each group and plotted. Higher dosages of AII were required to produce a significant correlation between pressure and IBI in the 5-week group compared to control. In the 11-week group, only the highest dosage yielded a significant correlation between pressure and IBI. When data were expressed in terms of the highest pressure and its corresponding IBI for each group, the 5-week-stress group had a shift in set point compared to control. The 11-week group showed a shift in set point and a reduction in gain compared to control animals. The similarity between these findings and those for other models of hypertension is discussed, with special emphasis on the potential role of the central nervous system.

Monoclonal antibody R7-3 recognized an erythroid specific cell surface molecule with a m.w. of approximately 98 kilodaltons (Kd) under nonreducing conditions and molecules of 40 and 44 Kd under reducing conditions on both embryonic- and adult-derived peripheral RBC. Immunochemical characterization, including limited peptide map analyses of these molecules, provided evidence that mAb R7-3 was recognizing the MHC coded B-G heterodimer. This is the first report of a monoclonal antibody that recognizes the B-G heterodimer. Affinity binding studies suggested that mAb R7-3 preferentially recognized the 44 Kd molecule. Immune depletion analyses demonstrated the presence of a single population of B-G heterodimers. Endoglycosidase-F and neuraminidase digestions suggested that the 44 and 40 Kd molecules contained very little, if any, carbohydrate. B-G heterodimer expression was examined on primitive and definitive RBC during embryonic development. B-G heterodimer expression was not detected on RBC of other avians.

The effect of maternal strain on reactivity to acute stress was studied in F1 reciprocals produced by crossing the spontaneously hypertensive rat (SHR) with its normotensive progenitor, the Wistar-Kyoto (WKY). This F1 generation, known as the borderline hypertensive rat (BHR), is genetically predisposed to develop hypertension in response to chronic stress or high dietary sodium. Reciprocals, considered to be genetically equivalent aside from sex-linked traits, differ in strain of dam during intrauterine and preweanling development. At 17 weeks of age, reciprocal F1 males did not differ in open-field behavior (squares crossed, rearings, and defecation measured over 3 days in 15-min sessions) or in home-cage measurements of mean arterial pressure (MAP) and heart rate (HR). However, different patterns of cardiovascular reactivity were displayed to transfer and footshock. While WKY-mothered rats reacted with graded pressor responses, SHR-mothered rats responded maximally to transfer, showed no additional increase to footshock, and maintained peak responding after footshock was terminated. Such reactivity differences may mediate the impact of environmental variables on the genetic disposition to hypertension.

Blood pressure and heart rate responses of the spontaneously hypertensive rat (SHR) and the Wistar-Kyoto rat (WKY) to mild restraint and tone-shock pairings were compared during a pre-stress, aversive conditioning and post-stress period, after five previous days of exposure to the paradigm. Although SHR and WKY showed similar responses to the onset of the pre-stress period, SHR showed significantly larger blood pressure responses following the onset of the conditioning than WKY. Furthermore, WKY showed a significant blood pressure and heart rate reduction during the conditioning session which was absent in the SHR. During the post-stress period, the blood pressure of SHR remained significantly elevated compared to their home cage rest values, but the blood pressure of WKY returned to basal levels. It is concluded that while the SHR is more reactive than the WKY to stimulus onset, the major source of between-strain differences after 20 min relates to differences in adaptation to continued environmental stimulation. This can lead to exaggerated estimates of physiological reactivity of the SHR, and is supportive of Folkow's view that SHR are both hyperreactive and show more prolonged defense reactions.

1. Sera from different embryonic stages of development and adult chickens were examined for embryonic-adult differences. 2. An antisera prepared in rabbits to 14 day embryonic chick sera revealed an antigen present in the early stages of embryonic development. The antigen reached a peak on day 14 and was not detectable 5 days post hatching. 3. Gel filtration studies in conjunction with immunodiffusion studies revealed the serum antigen to be in the 160,000 mol wt range. 4. Immunoelectrophoretic analyses of embryonic and adult sera revealed the sera components to increase in quantity and in numbers with development. The serum immunoelectrophoretic profile of newly hatch chick serum closely resembled sera from adult chickens. 5. Polyacrylamide gel electrophoretic comparisons of the sera of the developing chicks and the adult chickens revealed proteins specific to certain developmental stages as well as proteins specific to the adult serum. Qualitative and quantitative serum protein differences were found.

1. Chicken IgA purified from biliary fluids was chemically and immunologically characterized. 2. Chicken IgA was determined to be the only immunoglobulin class present in bile. Gel filtration studies reveal polymeric IgA e.g. 17-19S. 3. Antigenically, chicken IgA is distinct from chicken IgG, and IgM. 4. Chicken IgA does not show antigenic homology to human IgA. 5. SDS poly-acrylamide gel electrophoresis revealed IgA to possess heavy chains of 60,000 and light chains of 24,000 mol. wt, respectively. 6. Peptide mapping of tryptic digests of chicken alpha chains reveals approximately 35 peptides. The peptide map pattern is distinct from chicken gamma chains.

The antinociceptive effects of two different modes of nicotine administration were investigated using a within-subject design. Ten minimally-deprived, habitual smokers and fifteen ex-smokers were studied in separate experiments. Nicotine was delivered in research cigarettes and tobacco snuff. Pain was induced using the cold pressor test. Subjects in both experiments exhibited pain reduction after nicotine administration without changes in nicotine withdrawal. The results suggest that nicotine can produce physiological and psychological changes that are relevant to the reinforcement of smoking but are independent of the state of nicotine withdrawal.

1. A hemoglobin elution-staining procedure has been developed for distinguishing embryonic chick red blood cells from adult chicken red blood cells. 2. Adult hemoglobin is eluted from red blood cells with 1.9 M potassium phosphate buffer, pH 7.2; whereas, embryonic hemoglobin is retained within the cells and gives positive staining with erythrosin B. 3. The hemoglobin elution-staining pattern during development can be correlated with two embryonic hemoglobins as detected by polyacrylamide gel electrophoresis. 4. The series of red blood cells staining with erythrosin B correspond to the primary erythrocyte series suggesting that hemoglobin expression during development is correlated with different cell populations.

Antiserum prepared against sucrose gradient purified reticuloendotheliosis virus (REV) recognized the chicken transferrin receptor. Molecules immunoprecipitated from red blood cells (RBC) obtained from embryonic chickens with either the anti-REV reagent or a chicken transferrin immunomatrix were demonstrated to be identical by co-migration in both reducing and nonreducing SDS-polyacrylamide gels and in two-dimensional isoelectric focusing analyses, reciprocal immunodepletion analyses and by peptide mapping. The chicken transferrin receptor was shown to be a 190,000 dalton cell surface membrane molecule consisting of two similar disulfide-bonded subunits of approximately 95,000 daltons. The chicken transferrin receptor was expressed on erythroid cell surface membranes as 95,000 dalton monomers as well as 190,000 dalton dimers. The chicken transferrin receptor was expressed on all differentiation/maturation stages, including mature RBC, of both the primitive and definitive type I erythroid cell series. In adult chickens, the transferrin receptor was expressed by immature erythroid cells in the bone marrow, but not by mature circulating RBC. REV-transformed immature lymphoid cells and avian erythroblastosis virus (AEV)-transformed erythroid cells expressed dimers composed of 95,000 and 110,000 dalton subunits. Comparisons among V8 protease derived peptides from 95,000 dalton transferrin receptors obtained from RBC and REV-transformed lymphoid cells revealed a high degree of homology; however, the 95,000 dalton molecules isolated from REV-transformed lymphoid cells exhibited a 56,000 dalton peptide that was unique. Cloned AEV-transformed erythroleukemia cells induced to differentiate by supplementation of the media with 1 mM butyric acid expressed elevated transferrin receptor levels. Both serological and peptide mapping studies demonstrated the human transferrin receptor on K562 cells and the chicken transferrin receptor to be distinct. However, chicken transferrin was shown to be capable of reacting with the human transferrin receptors on K562 cells.

Spleen cells from 3-month-old chickens which had been surgically and chemically bursectomized were examined for rosette-forming lymphocytes (RFL). Finding no correlation between the degree of agammaglobulinemia in bursectomized chickens and the percentage of RFL in their spleens demonstrated a dissociation between two B-cell dependent functions, namely, immunoglobulin production and rosette-forming ability. In fact, the percentage of RFL in the spleens of agammaglobulinemic chickens was found to be slightly higher than those of normal chickens. The data indicate that RFL in spleens of normal chickens are B cells, and suggest the existence of a population of rosette-forming B lymphocytes in agammaglobulinemic bursectomized chickens.