Innate recognition of apoptotic cells: novel apoptotic cell-associated molecular patterns revealed by crossreactivity of anti-LPS antibodies

Cells dying by apoptosis are normally cleared by phagocytes through mechanisms that can suppress inflammation and immunity. Molecules of the innate immune system, the pattern recognition receptors (PRRs), are able to interact not only with conserved structures on microbes (pathogen-associated molecular patterns, PAMPs) but also with ligands displayed by apoptotic cells. We reasoned that PRRs might therefore interact with structures on apoptotic cells – apoptotic cell-associated molecular patterns (ACAMPs) – that are analogous to PAMPs. Here we show that certain monoclonal antibodies raised against the prototypic PAMP, lipopolysaccharide (LPS), can crossreact with apoptotic cells. We demonstrate that one such antibody interacts with a constitutively expressed intracellular protein, laminin-binding protein, which translocates to the cell surface during apoptosis and can interact with cells expressing the prototypic PRR, mCD14 as well as with CD14-negative cells. Anti-LPS cross reactive epitopes on apoptotic cells colocalised with annexin V- and C1q-binding sites on vesicular regions of apoptotic cell surfaces and were released associated with apoptotic cell-derived microvesicles (MVs). These results confirm that apoptotic cells and microbes can interact with the immune system through common elements and suggest that anti-PAMP antibodies could be used strategically to characterise novel ACAMPs associated not only with apoptotic cells but also with derived MVs.     

Investigating the loss of recruitment potential in red grouse (Lagopus lagopus scoticus): the relative importance of hen mortality,food supply,tick infestation and louping-ill

Ticks and their pathogens cause significant disease and economic loss in many animal populations. Despite this, experiments that test the impact of ticks and tick-borne diseases on wild animal populations are rare. Here, we report on an experiment assessing the effect of ticks on red grouse productivity and chick growth in relation to other causes of poor recruitment at two sites in the Scottish uplands during 2005. Treated hens received two leg bands impregnated with the acaricide permethrin, while controls hens were untreated. Chicks were captured at c.2 weeks of age and fitted with a metal patagial tag, and chicks from treated hens also received a permethrin-impregnated strip. Mean tick burdens in treated chicks were close to zero compared with a mean of around 12 in the control group. Although treatment reduced tick infestations, it did not increase brood size. Growth rates in chicks from control and treated hens were similar during the first 10 days and comparable with chicks fed an ad-lib invertebrate-based diet. These results suggest that in this case, neither ticks (and the tick transmitted louping-ill virus) nor food shortages was the main cause of chick mortality. However, mortality in the adult hens was around 35 %, and predation accounted for 62 % of these losses before broods fledged. Our results indicate that on our study sites, predation may have a more important impact on grouse population dynamics than ticks and tick-borne disease. We suggest that it may be more cost effective to determine the causes of poor grouse population performance before implementing popular but expensive tick control measures such as the culling of alternative hosts and running acaracide treated sheep ‘tick-mop’ flocks.     

Lactation Support and Breastfeeding Duration in Jaundiced Infants: A Randomized Controlled Trial

Objectives

Neonatal jaundice is the most common problem in full-term infants during the immediate post-natal period. We examined the effect of a lactation support intervention on breastfeeding duration in hospitalized jaundiced infants.

Study Design

We conducted a randomized controlled trial with a qualitative component involving mothers of hospitalized jaundiced breastfed infants <4 weeks of age. Mothers receiving the intervention met with an International Board-Certified Lactation Consultant in hospital and 1–3 times post discharge. Both groups received the standard care for jaundice. The primary outcome was exclusive breastfeeding at 3 months. To the exception of research assistants enrolling participants and completing qualitative interviews, all research staff, investigators and statisticians were blinded to group assignment. Qualitative interviews elicited feedback on breastfeeding experiences for both groups.

Results

99 participants were recruited, and 86 analyzed for primary outcome. There was no difference in exclusive breastfeeding at 3 months between groups (RR 0.84, 95% CI 0.56–1.24, p = 0.40) or in the secondary outcomes. 31 participants were included in the qualitative analysis. Participants in the intervention group described an increase in comfort and confidence levels with breastfeeding. Participants in the control group reported limited lactation support.

Conclusions

Our hospital-based lactation support program did not result in a higher proportion of mothers exclusively breastfeeding at 3 months compared to current hospital standard care. Qualitative feedback from the intervention group suggests that mothers’ confidence was increased, which is linked to breastfeeding duration. The decision to breastfeed is multifactorial and hospital-based lactation support may be only a small piece of the puzzle in hospitalized jaundiced infants. Further studies may be needed to fully elucidate the impact of an in-hospital lactation support program on successful breastfeeding for these infants.

Trial Registration

ClinicalTrials.gov NCT00966719 https://www.clinicaltrials.gov/ct2/show/NCT00966719?term=Lactation+Support+and+Breastfeeding+Duration+in+Jaundiced+Infants%3A+a+Randomized+Controlled+Trial&rank=1     

Qualitative analysis of stroke patients' motivation for rehabilitation

ObjectiveTo explore the attitudes and beliefs of stroke patients identified by professionals as having either “high” or “low” motivation for rehabilitation.DesignQualitative study with semistructured interviews.SettingThe stroke unit of an inner city teaching hospital.Participants22 patients with stroke who were undergoing rehabilitation; 14 with high motivation for rehabilitation and eight with low motivation.ResultsAll patients thought rehabilitation was important for recovery. High motivation patients were more likely to view rehabilitation as the most important means of recovery and to accord themselves an active role in rehabilitation. These patients were also more likely to understand rehabilitation and in particular to understand the specialist role of the nursing staff. Many patients reported independence at home as a personal goal, though few low motivation patients related this goal to success in rehabilitation. Information from professionals about rehabilitation, favourable comparisons with other stroke patients, and the desire to leave hospital had a positive effect on motivation. Conversely, overprotection from family members and professionals, lack of information or the receipt of “mixed messages” from professionals, and unfavourable comparisons with other patients had a negative effect.ConclusionsThere are some differences in beliefs between stroke patients identified as having low or high motivation for rehabilitation. These beliefs seem to be influenced by the environment in which the patient is rehabilitated. Professionals and carers should be made aware of the ways in which their behaviour can positively and negatively affect motivation.     

Persistence of duplicated PAC<Subscript>1</Subscript> receptors in the teleost, <Emphasis Type="Italic">Sparus auratus</Emphasis>

Background:  

Duplicated genes are common in vertebrate genomes. Their persistence is assumed to be either a consequence of gain of novel function (neofunctionalisation) or partitioning of the function of the ancestral molecule (sub-functionalisation). Surprisingly few studies have evaluated the extent of such modifications despite the numerous duplicated receptor and ligand genes identified in vertebrate genomes to date. In order to study the importance of function in the maintenance of duplicated genes, sea bream (Sparus auratus) PAC₁ receptors, sequence homologues of the mammalian receptor specific for PACAP (Pituitary Adenylate Cyclase-Activating Polypeptide), were studied. These receptors belong to family 2 GPCRs and most of their members are duplicated in teleosts although the reason why both persist in the genome is unknown.     

Facial fluctuating asymmetry is not associated with childhood ill-health in a large British cohort study

The idea that symmetry in facial traits is associated with attractiveness because it reliably indicates good physiological health, particularly to potential sexual partners, has generated an extensive literature on the evolution of human mate choice. However, large-scale tests of this hypothesis using direct or longitudinal assessments of physiological health are lacking. Here, we investigate relationships between facial fluctuating asymmetry (FA) and detailed individual health histories in a sample (n = 4732) derived from a large longitudinal study (Avon Longitudinal Study of Parents and Children) in South West England. Facial FA was assessed using geometric morphometric analysis of facial landmark configurations derived from three-dimensional facial scans taken at 15 years of age. Facial FA was not associated with longitudinal measures of childhood health. However, there was a very small negative association between facial FA and IQ that remained significant after correcting for a positive allometric relationship between FA and face size. Overall, this study does not support the idea that facial symmetry acts as a reliable cue to physiological health. Consequently, if preferences for facial symmetry do represent an evolved adaptation, then they probably function not to provide marginal fitness benefits by choosing between relatively healthy individuals on the basis of small differences in FA, but rather evolved to motivate avoidance of markers of substantial developmental disturbance and significant pathology.