A TriAdj-Adjuvanted Chlamydia trachomatis CPAF Protein Vaccine Is Highly Immunogenic in Pigs

Chlamydia trachomatis (Ct) infections are the most common sexually transmitted infection (STI). Despite effective antibiotics for Ct, undetected infections or delayed treatment can lead to infertility, ectopic pregnancies, and chronic pelvic pain. Besides humans, chlamydia poses similar health challenges in animals such as C. suis (Cs) in pigs. Based on the similarities between humans and pigs, as well as their chlamydia species, we use pigs as a large biomedical animal model for chlamydia research. In this study, we used the pig model to develop a vaccine candidate against Ct. The vaccine candidate consists of TriAdj-adjuvanted chlamydial-protease-like activity factor (CPAF) protein. We tested two weekly administration options-twice intranasal (IN) followed by twice intramuscular (IM) and twice IM followed by twice IN. We assessed the humoral immune response in both serum using CPAF-specific IgG (including antibody avidity determination) and also in cervical and rectal swabs using CPAF-specific IgG and IgA ELISAs. The systemic T-cell response was analyzed following in vitro CPAF restimulation via IFN-γ and IL-17 ELISpots, as well as intracellular cytokine staining flow cytometry. Our data demonstrate that while the IN/IM vaccination mainly led to non-significant systemic immune responses, the vaccine candidate is highly immunogenic if administered IM/IN. This vaccination strategy induced high serum anti-CPAF IgG levels with strong avidity, as well as high IgA and IgG levels in vaginal and rectal swabs and in uterine horn flushes. In addition, this vaccination strategy prompted a pronounced cellular immune response. Besides inducing IL-17 production, the vaccine candidate induced a strong IFN-γ response with CD4 T cells. In IM/IN-vaccinated pigs, these cells also significantly downregulated their CCR7 expression, a sign of differentiation into peripheral-tissue-homing effector/memory cells. Conclusively, this study demonstrates the strong immunogenicity of the IM/IN-administered TriAdj-adjuvanted Ct CPAF vaccine candidate. Future studies will test the vaccine efficacy of this promising Ct vaccine candidate. In addition, this project demonstrates the suitability of the Cs pre-exposed outbred pig model for Ct vaccine development. Thereby, we aim to open the bottleneck of large animal models to facilitate the progression of Ct vaccine candidates into clinical trials.

Systematic review of effectiveness and satisfaction evaluation in child and adolescent mental health services in Ireland

OBJECTIVES

Increasing numbers of youth experience mental illness, and also require and benefit from specialist child and adolescent mental health services (CAMHS). Worldwide, such services are underfunded and under-resourced, and services in Ireland are no different. It is vital that existing services are regularly reviewed for both efficacy and acceptability. Our objective was to review published studies evaluating service user satisfaction with CAMHS in Ireland and CAMHS therapeutic efficacy.

METHODS

MEDLINE, PsycINFO and CINAHL databases were systematically searched. Studies were included if they reported on service user satisfaction or an evaluation of CAMHS in Ireland.

RESULTS

From an initial 125 articles identified, 15 studies meet the inclusion criteria: four reporting on overall CAMHS satisfaction, three on satisfaction where a specific diagnosis was present, while eight evaluated various interventions offered. Whilst most service users perceived services to be satisfactory, important issues relating to accessibility were present. Evidence of efficacy was present for a small number of interventions, but studies were limited by methodological issues.

CONCLUSIONS

There is a dearth of studies evaluating CAMHS in Ireland. The extant literature suggests a positive experience once accessed, but long waiting times and poor collaboration are seen to limit services users' experience. More robust methodologically sound studies are urgently required. Given the expected increased demand linked to the current COVID-19 pandemic, coupled with the resultant compromised financial position, it is essential that scant resources are appropriately directed.

High yield expression in Pichia pastoris of human neutrophil elastase fused to cytochrome B5

Recombinant human neutrophil elastase (rHNE), a serine protease, was expressed in Pichia pastoris. Glycosylation sites were removed via bioengineering to prevent hyper-glycosylation (a common problem with this system) and the cDNA was codon optimized for translation in Pichia pastoris. The zymogen form of rHNE was secreted as a fusion protein with an N-terminal six histidine tag followed by the heme binding domain of Cytochrome B5 (CytB5) linked to the N-terminus of the rHNE sequence via an enteropeptidase cleavage site. The CytB5 fusion balanced the very basic rHNE (pI = 9.89) to give a colored fusion protein (pI = 6.87), purified via IMAC. Active rHNE was obtained via enteropeptidase cleavage, and purified via cation exchange chromatography, resulting in a single protein band on SDS PAGE (Mr = 25 KDa). Peptide mass fingerprinting analysis confirmed the rHNE amino acid sequence, the absence of glycosylation and the absence of an 8 amino acid C-terminal peptide as opposed to the 20 amino acids usually missing from the C-terminus of native enzyme. The yield of active rHNE was 0.41 mg/L of baffled shaker flask culture medium. Active site titration with alpha-1 antitrypsin, a potent irreversible elastase inhibitor, quantified the concentration of purified active enzyme. The Km of rHNE with methoxy-succinyl-AAPVpNA was identical with that of the native enzyme within the assay's limit of accuracy. This is the first report of full-length rHNE expression at high yields and low cost facilitating further studies on this major human neutrophil enzyme.

Prevalence of mental health disorders in children and adolescents in the Republic of Ireland: a systematic review

Referrals to Child and Adolescent Mental Health Services (CAMHS) have increased in recent years. Services are already under-resourced and the adverse psychological impact of Covid-19 is likely to increase demand. Accordingly, an understanding of prevalence of mental health (MH) disorders among youth is imperative to help inform and plan services.

AIM

To establish prevalence of MH disorders among youth (under 18) in Ireland.

METHOD

A systematic review using pre-defined search terms in PubMed, PsycInfo, Embase and CINAHL was conducted. Empirical studies conducted in Ireland, in youth and focusing on MH disorders were included.

RESULTS

From a total of 830 papers identified, 38 papers met inclusion criteria. Significant variation in rates of MH disorders was evident based on study methodology. Screening questionnaires for general psychopathology reported rates of 4.8-17.8% scoring above clinical cut-offs, with higher rates for ADHD (7.3%). Studies examining depression ranged from 4% to 20.8%, while rates for 'current' MH disorder, determined by semi-structured interview, were 15.5%, while 'lifetime' rates varied from 19.9% to 31.2%. Fewer than half (44%) of those identified as 'in need' of specialist MH services were accessing CAMHS.

CONCLUSION

Data on MH disorders among Irish youth is limited, and studies showed significant variance in rates, making service planning difficult. There is an urgent need for serial epidemiological surveys, with clear operational criteria for clinically impairing MH difficulties. Such studies are essential to understand potential demand and service planning. This is most urgent given the expected increased demand post Covid-19.

A Versatile and Robust Serine Protease Inhibitor Scaffold from Actinia tenebrosa

Serine proteases play pivotal roles in normal physiology and a spectrum of patho-physiological processes. Accordingly, there is considerable interest in the discovery and design of potent serine protease inhibitors for therapeutic applications. This led to concerted efforts to discover versatile and robust molecular scaffolds for inhibitor design. This investigation is a bioprospecting study that aims to isolate and identify protease inhibitors from the cnidarian Actinia tenebrosa. The study isolated two Kunitz-type protease inhibitors with very similar sequences but quite divergent inhibitory potencies when assayed against bovine trypsin, chymostrypsin, and a selection of human sequence-related peptidases. Homology modeling and molecular dynamics simulations of these inhibitors in complex with their targets were carried out and, collectively, these methodologies enabled the definition of a versatile scaffold for inhibitor design. Thermal denaturation studies showed that the inhibitors were remarkably robust. To gain a fine-grained map of the residues responsible for this stability, we conducted in silico alanine scanning and quantified individual residue contributions to the inhibitor's stability. Sequences of these inhibitors were then used to search for Kunitz homologs in an A. tenebrosa transcriptome library, resulting in the discovery of a further 14 related sequences. Consensus analysis of these variants identified a rich molecular diversity of Kunitz domains and expanded the palette of potential residue substitutions for rational inhibitor design using this domain.

Method of self-harm and risk of self-harm repetition: findings from a national self-harm registry

BACKGROUND

Risk of self-harm repetition has consistently been shown to be higher following self-cutting compared to intentional drug overdose (IDO) and other self-harm methods. The utility of previous evidence is limited due to the large heterogeneous method categories studied. This study examined risk of hospital presented self-harm repetition according to specific characteristics of self-harm methods.

METHODS

Data on consecutive self-harm presentations to hospital emergency departments (2010-2016) were obtained from the National Self-Harm Registry Ireland. Associations between self-harm method and repetition were analysed using survival analyses.

RESULTS

Overall, 65,690 self-harm presentations were made involving 46,661 individuals. Self-harm methods associated with increased repetition risk included minor self-cutting, severe self-cutting, multiple drug IDOs involving psychotropic drugs and self-harm by blunt object. Minor self-cutting was the method associated with highest repetition risk (adjusted hazard ratio (AHR) 1.38, 95% CI 1.31-1.45). Risk of repetition was comparable following IDOs of four or more drugs involving psychotropic drugs (AHR = 1.29, 95% CI 1.20-1.39), severe self-cutting (AHR 1.25, 95% CI 1.16-1.34) and blunt object (AHR = 1.23, 95% CI 1.07-1.42).

LIMITATIONS

Information was not available on suicide or other causes of mortality.

CONCLUSIONS

Self-harm method and the associated risk of repetition should form a core part of biopsychosocial assessments and should inform follow-up care for self-harm patients. The observed differences in repetition associated with specific characteristics of IDO underline the importance of safety planning and monitoring prescribing for people who have engaged in IDO.

Conscientiousness and adherence to the oral contraceptive pill: A prospective study

OBJECTIVE

We assess the association between conscientiousness and adherence to the oral contraceptive pill (OCP), and examine if such a relationship is independent of a measure of prospective memory and a range of social cognitive variables.

METHOD

Data were collected from 150 OCP users at baseline, and 99 provided follow-up data four weeks later. Conscientiousness, a range of social cognitive predictors and prospective memory were assessed at baseline. OCP adherence was measured at baseline, and again at Time 2. Data were analysed using correlation and multiple linear regression.

RESULTS

Higher conscientiousness was associated with higher overall OCP adherence in both cross-sectional (r = -0.28, p < 0.01) and prospective analysis (r = -0.34, p < 0.01). Conscientiousness predicted OCP adherence at Time 2, adjusting for OCP adherence at Time 1 (R(2) change = 0.02, p = 0.04). The association was reduced to non-significance when social cognitive predictors and prospective memory were included in the multivariable model. Prospective memory was an independent predictor of OCP adherence at Time 2.

DISCUSSION

This is the first study to identify an association between conscientiousness and OCP adherence. The association is not independent from social cognitive predictors and prospective memory. Facet-level analysis of conscientiousness and formal mediation analyses are recommended in future replications.

Can general practice help address youth mental health? A retrospective cross-sectional study in Dublin's south inner city

AIMS

With general practice potentially having an important role in early intervention of mental and substance use disorders among young people, we aim to explore this issue by determining the prevalence of psychological problems and general practice/health service utilization among young people attending general practice.

METHODS

A retrospective cross-sectional study of patients attending three general practices in Dublin city.

RESULTS

Among a sample of young people (mostly women, 44% general medical services (GMS) eligible), we observed considerable contact with general practice, both lifetime and for the 2 years of the study. The mean consultation rate was 3.9 consultations in 2 years and psychosocial issues (most commonly stress/anxiety and depression) were documented in 35% of cases. Identification of psychosocial issues was associated with GMS eligibility, three or more doctor consultations, and documentation of smoking and drinking status.

CONCLUSIONS

Psychosocial issues are common among young people attending general practice and more work on their epidemiology and further identification in general practice are advocated.

Mutations of FLT3/ITD confer resistance to multiple tyrosine kinase inhibitors

FMS-like tyrosine kinase 3 (FLT3) normally functions in the survival/proliferation of hematopoietic stem/progenitor cells, but its constitutive activation by internal tandem duplication (ITD) mutations correlates with a poor prognosis in AML. The development of FLT3 tyrosine kinase inhibitors (TKI) is a promising strategy, but resistance that arises during the course of treatment caused by secondary mutations within the mutated gene itself poses a significant challenge. In an effort to predict FLT3 resistance mutations that might develop in patients, we used saturation mutagenesis of FLT3/ITD followed by selection of transfected cells in FLT3 TKI. We identified F621L, A627P, F691L and Y842C mutations in FLT3/ITD that confer varying levels of resistance to FLT3 TKI. Western blotting confirmed that some FLT3 TKI were ineffective at inhibiting FLT3 autophosphorylation and signaling through MAP kinase, STAT5 and AKT in some mutants. Balb/c mice transplanted with the FLT3/ITD Y842C mutation confirmed resistance to sorafenib in vivo but not to lestaurtinib. These results indicate a growing number of FLT3 mutations that are likely to be encountered in patients. Such knowledge, combined with known remaining sensitivity to other FLT3 TKI, will be important to establish as secondary drug treatments that can be substituted when these mutants are encountered.

P5-02-01: ErbB4 Ectodomain as a Biomarker and a Potential Therapeutic Target for Breast Cancer

ErbB4 function is controversial in breast cancer and influenced by alternative splicing of the ERBB4 gene. Here we evaluated the cleavable ErbB4 JM-a isoform as a potential drug target and biomarker. To address ErbB4 cleavage in breast cancer tissues in vivo, extracellular and intracellular cleavage products of ErbB4 were assessed by ELISA and immunohistochemistry using matched serum and tissue samples from a series of 243 breast cancer patients. Elevated serum ectodomain level (≥40 ng/mL) and nuclear immunoreactivity were present in 21% and 52% of the patients, respectively. An elevated serum ErbB4 ectodomain concentration was not associated with tumor nuclear immunoreactivity, but was significantly associated with the premenopausal status at diagnosis (P = 0.04). Estradiol also enhanced ErbB4 cleavage and ErbB4 cleaving enzyme activity in vitro, supporting a role for estrogen signaling in regulation of ErbB4 cleavage. Selective targeting of the cleavable ErbB4 JM-a in human breast cancer cells with an ErbB4 isoform-specific mAb 1479 inhibited ErbB4 cleavage and reduced tumor formation in a mouse xenograft model. Consistent with blocking of ErbB4 cleavage, mutagenesis studies and the 3.4 Å X-ray crystal structure of a complex of the ErbB4 extracellular region and the 1479 Fab localized the binding site of mAb 1479 on ErbB4 to a region on subdomain IV encompassing JM-a-specific residues. These data demonstrate that ErbB4 is cleaved in a subset of breast cancer patients, and suggest that the mechanisms by which mAb 1479 suppresses breast cancer cell growth involves inhibition of ErbB4 cleavage. Serum ErbB4 ectodomain concentration could be used as a biomarker to monitor the activity of compounds, such as mAb 1479, that target ErbB4 cleavage.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-02-01.

Immobilization of lmmunoreactants on Solid Phases for ELlSAs

Enzyme-linked immunosorbent assays (ELISAs) can be designed to detect either antigens or antibodies. Nearly all ELISA formats require the separation of reactants from the products of the immunoassay. The product of the assay is an immune complex consisting of target ligand, the analyte, and the reporting probe used to detect the complex that is formed. Because it 1s usually necessary to remove excess analyte as well as excess probe before measurements, several separation steps may be desired, if not required. In the early years, during the evolution of radioimmunoassays (RIAs), it was found that, under certain conditions, antibodies or antigens would bind strongly during brief exposures of solutions to plastic surfaces, such as the inner walls of a tube or a well. The amount of target ligand that would bind proved to be well suited for the competitive assays that were being developed then; the convenience that this phenomen provided has spurred the growth of immunoassay systems for 25 years. Although ELISAs have now generally replaced most RIAs, the principles for coating of the solid phases are similar for both.

Search for retrovirus in patients with multiple sclerosis

Multiple sclerosis (MS) patient samples were screened for known or novel retroviruses using an ultrasensitive technique, IMx PERT, that detects the presence of reverse transcriptase (RT). This procedure has 10(5)- to 10(7)-fold greater sensitivity than conventional RT assays and is capable of detecting 10 to 50 virions. Moreover, IMx PERT is at least as sensitive as polymerase chain reaction, and requires no previous knowledge of viral nucleotide sequence. The MS specimens analyzed in this study included 136 sera from 79 patients and 128 cerebrospinal fluid samples from 53 patients with relapsing or chronic progressive disease. In addition, peripheral blood mononuclear cells from 19 MS patients were cultured in an attempt to amplify or induce expression of low-copy number or cell-associated retrovirus. No evidence of retrovirus was found in any of the specimens obtained from MS patients.

A novel semi-automated paramagnetic microparticle based enzyme immunoassay for hepatitis C virus: its application to serologic testing

A new rapid serologic enzyme immunoassay for antibodies to hepatitis C virus (HCV) is described. The assay combines synthetic peptide and recombinant antigens representing putative structural and non structural HCV gene products with paramagnetic microparticle assay (MP assay) technology. Assay readout is based upon an enzymatically generated fluorescent product which is quantified with a novel semi-automated washer/reader instrument system. Assay sensitivity and specificity was determined to be greater than the first generation HCV C-100 EIA using a non-A, non-B hepatitis disease panel, an HCV performance panel, an HCV seroconversion panel, dilutions of HCV reactive sera, and random volunteer blood donor specimens.

Improved serologic detection of hepatitis C virus with a paramagnetic microparticle assay using multiple antigenic sequences

A paramagnetic microparticle (MP) assay for antibody to hepatitis C virus (anti-HCV) was developed, in which the probe for antibody consisted of synthetic peptides corresponding to HCV capsid and nonstructural c-100 regions, as well as a recombinant protein corresponding to the nonstructural c33c region. Assay performance was evaluated by testing serum from 108 geographically diverse patients with non-A, non-B hepatitis (NANBH). The frequency of anti-HCV reactivity detected with the MP assay and with an enzyme-linked immunosorbent assay (ELISA) for c-100 was 91 and 70 percent, respectively. All c-100 HCV ELISA-reactive specimens also reacted on the MP assay. In addition, anti-HCV seroconversion in three plasma donors was detected one to two blood collection dates earlier by the MP assay than by the c-100 HCV ELISA and at similar blood collection dates by the MP assay and a second-generation anti-HCV ELISA. Serologic responses to the three distinct antigenic regions of HCV in NANBH patients varied: reactivity to all three antigens was most common (49%), reactivity to both capsid and c33c (40%) was next most common, and single-antigen reactivity was rare (4%). MP assay reactivity of 825 volunteer donors was 0.1 percent. These results demonstrate both the utility of additional HCV antigens for an effective anti-HCV screening assay and the application of paramagnetic MP technology to serologic testing for HCV infection.

In vitro studies of intestinal drug absorption. Determination of partition and distribution coefficients with brush border membrane vesicles

Brush border membrane vesicles (BBMV) were isolated from rat small intestine and characterized in terms of relative enrichment of specific organelle marker enzymes (20-fold enrichment; 20% yield), contamination by other subcellular organelles (less than 1%) and functional integrity (Na(+)-dependent glucose uptake). Using these vesicles, techniques were developed for the determination of partition and distribution coefficients for the model solutes, nitrobenzene, toluene and benzoic acid. No gender, age or regional variation along the small intestine in partition coefficient (log P) values was detected. There was no temperature (10-40 degrees) or pH (4.5-8.0) dependence in partition coefficients of nitrobenzene and toluene. Fair agreement was obtained for log P and log D values for these two solutes determined with BBMV and those reported with octanol and propylene glycol dipelargonate. Selective removal of proteins, both ecto-brush border and micro-villus core proteins, did not alter the partition coefficients of the three model solutes. In contrast, depletion of the BBMV of non-esterified fatty acids significantly decreased the partition coefficients. Liposomes prepared from BBMV lipid extracts were also used for partition coefficient determinations and gave similar values to intact BBMV; addition of increasing amounts of cholesterol to the lipid extract caused small increases in the partition coefficients of the model solutes in the liposomes. It was concluded that the partition coefficients of the BBMV were related to the lipid and not to the protein composition of the vesicles. The method offers a rapid and reliable means of measuring the partition coefficient of non-protein bound drugs and nutrients in isolated intestinal BBMV and should assist in the subsequent modelling and prediction of intestinal absorption in vivo.

Contribution of tryptophan residues to the combining site of a monoclonal anti dinitrophenyl spin-label antibody

Two Fab fragments of the monoclonal anti dinitrophenyl (DNP) spin-label antibody AN02 were prepared by recombination of specifically deuterated heavy and light chains. In the recombinant H(I)L(II) all the tyrosines and phenylalanines were perdeuterated as were the tryptophan residues of the heavy chain. In the recombinant H(II)L(I) all the tyrosines and phenylalanines were perdeuterated as were the tryptophan residues of the light chain. Saturation of three resonances of H(I)L(II), assigned to tryptophan protons of the light chain, resulted in magnetization transfer to the aromatic proton at position 6 of the DNP ring and to the CH2 protons of the glycines linked to the DNP in a diamagnetic hapten (DNP-DG). Saturation of three resonances of H(II)L(I) assigned to tryptophan protons of the heavy chain resulted in magnetization transfer to the CH2 protons of the glycines in DNP-DG. From the dependence of the magnetization transfer on the irradiation time, the cross relaxation rates between the involved protons were estimated. The inferred distances between these protons of the hapten and certain tryptophan protons are 3-4 A. It is concluded that in the combining site of AN02 there is one tryptophan from the light chain and one tryptophan from the heavy chain that are very near the hapten. When all tyrosines and phenylalanines were perdeuterated and all tryptophan aromatic protons were deuterated except for the protons at positions 2 and 5, titration of the Fab fragments with variable amounts of paramagnetic hapten showed that one proton from the light chain tryptophan is near (less than 7 A) the unpaired electron and that three other protons are significantly closer than 15 A.(ABSTRACT TRUNCATED AT 250 WORDS)