Humoral immune response in lactating dairy cows after repeated exposure to human chorionic gonadotropin

Our objective was to determine if repeated exposure of lactating dairy cows to human chorionic gonadotropin (hCG) would induce an antibody (Ab) response against hCG. Cows either received an hCG injection (hCG; n = 24, each given 2000 IU im) or no treatment (CON; n = 22) 18 days after a timed AI (TAI) and 7 days before initiation of Ovsynch for resynchronization of ovulation and TAI. A subgroup of cows continued in the experiment to receive a second hCG injection (n = 17) 35 days after the first exposure to hCG, whereas another subgroup served as controls (n = 9). Another subgroup of cows continued in the experiment to receive a third hCG injection (n = 11) 35 days after the second exposure to hCG, whereas cows not receiving hCG served as controls (n = 8). A binding radioimmunoassay was used to detect hCG antibodies in serum samples collected 0, 7, 14, 21, and 28 days after treatment. A positive Ab response (>6.2% bound) was defined as three standard deviations above CON binding. No cows had hCG antibodies at Day 0 before the first exposure to hCG. After the first hCG treatment, there was no difference (P = 0.52) between Ab positive cows in CON (0%) and hCG (4%) treatments. At the second hCG treatment, on Day 0 there was no difference (P = 0.65) between CON (0%) and hCG (6%) cows, whereas, more (P = 0.02) hCG cows (47%) were positive than CON cows (0%) within 28 days of the hCG injection. At the third hCG injection, hCG cows tended (P = 0.09) to have a greater percentage of Ab positive (36%) than CON cows (0%), whereas after the injection, a greater (P < 0.01) percentage of hCG cows were positive (hCG = 73% vs. CON = 0%). After the second and third exposure to hCG, 8 of 17 and 8 of 11 cows within the hCG group had greater percent Ab bound at 7, 14, 21, and 28 days after hCG than cows in CON and those with no Ab response. The greatest percent Ab binding occurred at 14 days after the second and third hCG exposure. We concluded that some but not all lactating dairy cows developed an Ab response after repeated exposure to hCG and that maximum response occurred within 14 days after hCG exposure.     

硫化氢在心血管保护过程中免疫炎症调节研究进展

硫化氢(hydrogen sulfide,H_2S)是一种无色、具有臭鸡蛋气味的气体,过去认为只是一种有毒的气体。近年来大量研究证实H_2S是继一氧化氮(nitric oxide,NO)和一氧化碳(carbon oxide,CO)后第三种内源性气体信号分子,同时,H_2S在心血管系统疾病发生、发展过程中起关键的调控作用,但其机制还不明确,已有报道主要通过抗凋亡、抗氧化、调节内皮一氧化氮合酶活性、促进血管新生等;而本文总结了H_2S在缺血性心脏病、动脉粥样硬化等心血管疾病中免疫炎症调节作用及其机制,从而为H_2S生物学功能以及相关心血管疾病的防治提供新的思路。     

A phenotypic and molecular characterization of the fmr1-tm1Cgr fragile X mouse

Fragile X Syndrome is the most common form of inherited mental retardation. It is also known for having a substantial behavioral morbidity, including autistic features. In humans, Fragile X Syndrome is almost always caused by inactivation of the X-linked FMR1 gene. A single knockout mouse model, fmr1-tm1Cgr, exists. In this report we further characterize the cognitive and behavioral phenotype of the fmr1-tm1Cgr Fragile X mouse through the use of F1 hybrid mice derived from two inbred strains (FVB/NJ and C57BL/6J). Use of F1 hybrids allows focus on the effects of the fmr1-tm1Cgr allele with reduced influence from recessive alleles present in the parental inbred strains. We find that the cognitive phenotype of fmr1-tm1Cgr mice, including measures of working memory and learning set formation that are known to be seriously impacted in humans with Fragile X Syndrome, are essentially normal. Further testing of inbred strains supports this conclusion. Thus, any fmr1-tm1Cgr cognitive deficit is surprisingly mild or absent. There is, however, clear support presented for a robust audiogenic seizure phenotype in all strains tested, as well as increased entries into the center of an open field. Finally, a molecular examination of the fmr1-tm1Cgr mouse shows that, contrary to common belief, it is not a molecular null. Implications of this finding for interpretation of the phenotype are discussed.     

The habitat disruption induces immune-suppression and oxidative stress in honey bees

The honey bee is a major insect used for pollination of many commercial crops worldwide. Although the use of honey bees for pollination can disrupt the habitat, the effects on their physiology have never been determined. Recently, honey bee colonies have often collapsed when introduced in greenhouses for pollination in Japan. Thus, suppressing colony collapses and maintaining the number of worker bees in the colonies is essential for successful long-term pollination in greenhouses and recycling of honey bee colonies. To understand the physiological states of honey bees used for long-term pollination in greenhouses, we characterized their gene expression profiles by microarray. We found that the greenhouse environment changes the gene expression profiles and induces immune-suppression and oxidative stress in honey bees. In fact, the increase of the number of Nosema microsporidia and protein carbonyl content was observed in honey bees during pollination in greenhouses. Thus, honey bee colonies are likely to collapse during pollination in greenhouses when heavily infested with pathogens. Degradation of honey bee habitat by changing the outside environment of the colony, during pollination services for example, imposes negative impacts on honey bees. Thus, worldwide use of honey bees for crop pollination in general could be one of reasons for the decline of managed honey bee colonies.     

Time-Dependent Increase in Protein Phosphorylation Following One-Trial Enhancement in Hermissenda

Abstract: One-trial conditioning of the nudibranch mollusk Hermissenda produces short- and long-term changes in excitability (enhancement) of identified sensory neurons. To investigate the biochemical mechanisms underlying this example of plasticity, we have examined changes in protein phosphorylation at different times following the in vitro conditioning trial. Changes in the incorporation of ³²PO₄ into proteins were determined using two-dimensional polyacrylamide gel electrophoresis, autoradiography, and densitometry. Conditioning resulted in increases in levels of several phosphoproteins, five of which, ranging in apparent molecular mass from 22 to 55 kDa, were chosen for analysis. The increased phosphorylation of the 46- and 55-kDa phosphoproteins detected 2 h postconditioning was significantly greater than the level of phosphorylation detected in an unpaired control group, indicating that long-term enhancement is pairing specific. Statistically significant increases in phosphorylation as compared with the control group that received only light were detected immediately after conditioning (5 min) for the 55-, 46-, and 22-kDa phosphoproteins, at 1 h for the 55- and 46-kDa phosphoproteins, and at 2 h for the 55-, 46-, and 22-kDa phosphoproteins. The 46- and 55-kDa phosphoproteins are putative structural proteins, and the 22-kDa phosphoprotein is proposed to be a protein kinase C substrate previously identified in Hermissenda following multitrial classical conditioning. Time-dependent increases in protein phosphorylation may contribute to the induction and maintenance of different memory stages expressed in sensory neurons after one-trial conditioning.     

Trichinella spiralis: strong antibody response to a 49 kDa newborn larva antigen in infected rats

In this work, we analyzed the kinetics of anti-Trichinella spiralis newborn larva (NBL) antibodies (Ab) and the antigenic recognition pattern of NBL proteins and its dose effects. Wistar rats were infected with 0, 700, 2000, 4000 and 8000 muscle larvae (ML) and bled at different time intervals up to day 31 post infection (p.i.). Ab production was higher with 2000 ML dose and decreased with 8000, 4000 and 700 ML. Abs were not detected until day 10, peaked on day 14 for the 2000 ML dose and on day 19 for the other doses and thereafter declined slowly from 19 to 31 days p.i. In contrast, Abs to ML increased from day 10, peaked on day 19 and remained high until the end of the study. Abs bound strongly at least to three NBL components of 188, 205 and 49 kDa. NBL antigen of 188 and 205 kDa were recognized 10-26 days p.i. and that of 49 kDa from day 10 to day 31 p.i. A weak recognition towards antigens of 52, 54, 62 and 83 kDa was also observed during the infection. An early recognition of 31, 43, 45, 55, 68 and 85 kDa ML antigens was observed whereas the response to those of 43, 45, 48, 60, 64 and 97 kDa (described previously as TSL-1 antigens) occurred late in the infection. A follow-up of antigen recognition up to day 61 with the optimal immunization dose (2000 ML) evidenced a decline of Ab production to the 49 kDa NBL antigen 42 days p.i., which suggested antigenic differences with the previously reported 43 kDa ML antigen strongly recognized late in the infection. To analyze the stage-specificity of the 49 kDa NBL antigen, polyclonal antibodies (PoAb) were obtained in rats immunized with 49 kDa NBL antigen. PoAb reacted strongly with the 49 kDa NBL component in NBL total soluble extract but no reactivity was observed with soluble antigen of the other T. spiralis stages. Albeit with less intensity, the 49 kDa component was also recognized by PoAb together with other antigens of 53, 97 and 107 kDa, in NBL excretory-secretory products (NBL-ESP). Thus, our results reveal differences in the kinetics of anti-NBL and ML Ab responses. While anti-NBL Abs declined slowly from day 19 until the end of the experiment, Abs to ML antigen remained high in the same period. It is remarkable the optimal Ab response to NBL antigens with 2000 ML infective dose and the reduced number of NBL antigens identified throughout the experimental T. spiralis infection, standing out the immunodominant 49 kDa antigen. Interestingly, this antigen, which was prominently expressed in NBL somatic proteins, was also detected in NBL-ESP.     

Independent sources of condition dependency and multiple pathways determine a composite trait: lessons from carotenoid‐based plumage colouration

Many colour ornaments are composite traits consisting of at least four components, which themselves may be more complex, determined by independent evolutionary pathways, and potentially being under different environmental control. To date, little evidence exists that several different components of colour elaboration are condition dependent and no direct evidence exists that different ornamental components are affected by different sources of variation. For example, in carotenoid‐based plumage colouration, one of the best‐known condition‐dependent ornaments, colour elaboration stems from both condition‐dependent pigment concentration and structural components. Some environmental flexibility of these components has been suggested, but specifically which and how they are affected remains unknown. Here, we tested whether multiple colour components may be condition dependent, by using a comprehensive 3 × 2 experimental design, in which we carotenoid supplemented and immune challenged great tit nestlings (Parus major) and quantified effects on different components of colouration. Plumage colouration was affected by an interaction between carotenoid availability and immune challenge. Path analyses showed that carotenoid supplementation increased plumage saturation via feather carotenoid concentration and via mechanisms unrelated to carotenoid deposition, while immune challenge affected feather length, but not carotenoid concentration. Thus, independent condition‐dependent pathways, affected by different sources of variation, determine colour elaboration. This provides opportunities for the evolution of multiple signals within components of ornamental traits. This finding indicates that the selective forces shaping the evolution of different components of a composite trait and the trait's signal content may be more complex than believed so far, and that holistic approaches are required for drawing comprehensive evolutionary conclusions.