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Background: The RTS,S/AS01E malaria vaccine has moderate efficacy, lower in infants than children. Current efforts to enhance RTS,S/AS01E efficacy would benefit from learning about the vaccine-induced immunity and identifying correlates of malaria protection, which could, for instance, inform the choice of adjuvants. Here, we sought cellular immunity-based correlates of malaria protection and risk associated with RTS,S/AS01E vaccination., Methods: We performed a matched case-control study nested within the multicenter African RTS,S/AS01E phase 3 trial. Children and infant samples from 57 clinical malaria cases (32 RTS,S/25 comparator vaccinees) and 152 controls without malaria (106 RTS,S/46 comparator vaccinees) were analyzed. We measured 30 markers by Luminex following RTS,S/AS01E antigen stimulation of cells 1 month postimmunization. Crude concentrations and ratios of antigen to background control were analyzed., Results: Interleukin (IL) 2 and IL-5 ratios were associated with RTS,S/AS01E vaccination (adjusted P ≤ .01). IL-5 circumsporozoite protein (CSP) ratios, a helper T cell type 2 cytokine, correlated with higher odds of malaria in RTS,S/AS01E vaccinees (odds ratio, 1.17 per 10% increases of CSP ratios; P value adjusted for multiple testing = .03). In multimarker analysis, the helper T cell type 1 (TH1)-related markers interferon-γ, IL-15, and granulocyte-macrophage colony-stimulating factor protected from subsequent malaria, in contrast to IL-5 and RANTES, which increased the odds of malaria., Conclusions: RTS,S/AS01E-induced IL-5 may be a surrogate of lack of protection, whereas TH1-related responses may be involved in protective mechanisms. Efforts to develop second-generation vaccine candidates may concentrate on adjuvants that modulate the immune system to support enhanced TH1 responses and decreased IL-5 responses., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

The mucosal immune system must initiate and regulate protective immunity, while balancing this immunity with tolerance to harmless antigens and bacterial commensals. We have explored the hypothesis that mucosal dendritic cells (DC) control the balance between regulation and immunity, by studying the responses of human tonsil-derived DC to Neisseria meningitidis as a model organism. We show that tonsil DC are able to sample their antigenic environment, internalizing Nm and expressing high levels of HLA-DR and CD86. However, in comparison to monocyte-derived DC (moDC), they respond to pathogen encounter with only low level cytokine production, largely dominated by TGFβ. Functionally, tonsil DC also only stimulated low levels of antigen-specific T cell proliferation and cytokine production when compared to moDC. We therefore propose that the default role for DC in the nasopharynx is to maintain tolerance/ignorance of the large volume of harmless antigens and bacterial commensals encountered at the nasopharyngeal mucosa.

Objective: Pediatric psychologists are often interested in finding patterns in heterogeneous longitudinal data. Latent variable mixture modeling is an emerging statistical approach that models such heterogeneity by classifying individuals into unobserved groupings (latent classes) with similar (more homogenous) patterns. The purpose of the second of a 2-article set is to offer a nontechnical introduction to longitudinal latent variable mixture modeling., Methods: 3 latent variable approaches to modeling longitudinal data are reviewed and distinguished., Results: Step-by-step pediatric psychology examples of latent growth curve modeling, latent class growth analysis, and growth mixture modeling are provided using the Early Childhood Longitudinal Study-Kindergarten Class of 1998-1999 data file., Conclusions: Latent variable mixture modeling is a technique that is useful to pediatric psychologists who wish to find groupings of individuals who share similar longitudinal data patterns to determine the extent to which these patterns may relate to variables of interest.

Objective: Pediatric psychologists are often interested in finding patterns in heterogeneous cross-sectional data. Latent variable mixture modeling is an emerging person-centered statistical approach that models heterogeneity by classifying individuals into unobserved groupings (latent classes) with similar (more homogenous) patterns. The purpose of this article is to offer a nontechnical introduction to cross-sectional mixture modeling., Method: An overview of latent variable mixture modeling is provided and 2 cross-sectional examples are reviewed and distinguished., Results: Step-by-step pediatric psychology examples of latent class and latent profile analyses are provided using the Early Childhood Longitudinal Study-Kindergarten Class of 1998-1999 data file., Conclusions: Latent variable mixture modeling is a technique that is useful to pediatric psychologists who wish to find groupings of individuals who share similar data patterns to determine the extent to which these patterns may relate to variables of interest.

Background: African adults infected with human immunodeficiency virus (HIV) have high rates of pneumococcal colonization and invasive disease. Here we have investigated the possibility that HIV disrupts the normal balance of pneumococcal-specific helper T cell (Th) 1/Th17 immunity to colonization, resulting in a more permissive nasopharyngeal niche., Methods: One hundred thirty-six HIV-infected and -uninfected Malawian adults were enrolled in the study. Changes in rates and composition of nasopharyngeal pneumococcal colonization were analyzed using microarray. The underlying pneumococcal-specific Th1/Th17 responses associated with altered pneumococcal colonization were investigated using flow cytometry., Results: We find that pneumococcal carriage is only modestly increased in asymptomatic HIV-infected Malawian adults but that colonization rates rise dramatically during symptomatic disease (HIV(neg) 13%, HIV(asy) 19%, and HIV(sym) 38%). These rates remain high in subjects established on antiretroviral therapy (ART): 33% (at 6-12 months) and 52% (at 18 months), with HIV-infected individuals carrying a broader range of invasive and noninvasive serotypes compared with HIV-negative controls. The frequency of multiple serotype carriage (>1 serotype HIV(neg) 26%, HIV(asy) 30%, HIV(sym) 31%, HIV(ART) 31%) is not affected. These changes in colonization are associated with generalized CD4 T-cell depletion, impaired antigen-specific proliferation, and a defect in pneumococcal-specific T-cell interferon-γ but not interleukin 17 production., Conclusions: These data reveal the persistently poor control of pneumococcal colonization in HIV-infected adults following immune ART-mediated reconstitution, highlighting a potential reservoir for person-to-person spread and vaccine escape. Novel approaches to control colonization either through vaccination or through improvements in the quality of immune reconstitution are required.

Invasive pneumococcal disease is a leading cause of human immunodeficiency virus (HIV)-associated mortality in sub-Saharan African children. Defective T-cell-mediated immunity partially explains this high disease burden, but there is an increased risk of invasive pneumococcal disease even in the context of a relatively preserved percentage of CD4 cells. We hypothesized that impaired B-cell immunity to this pathogen further amplifies the immune defect. We report a shift in the B-cell compartment toward an apoptosis-prone phenotype evident early in HIV disease progression. We show that, although healthy HIV-uninfected and minimally symptomatic HIV-infected children have similar numbers of isotype-switched memory B cells, numbers of pneumococcal protein antigen-specific memory B cells were lower in HIV-infected than in HIV-uninfected children. Our data implicate defective naturally acquired B-cell pneumococcal immunity in invasive pneumococcal disease causation in HIV-infected children and highlight the need to study the functionality and duration of immune memory to novel pneumococcal protein vaccine candidates in order to optimize their effectiveness in this population.

Objective: To test the measurement equivalence of the Youth Life Orientation Test (YLOT) in children with cancer (N = 199) and healthy controls (N = 108), and to examine optimism and pessimism as predictors of children's health-related quality of life (HRQL)., Methods: Confirmatory factor analysis (CFA) was conducted to establish the two factor structure of the YLOT and to test for metric invariance., Results: A two-factor structure for the YLOT was confirmed and found to be stable across our study groups. There were no differences in mean levels of optimism and pessimism between cancer patients and controls after controlling for race/ethnicity. Higher optimism was associated with lower self-reports of pain and better emotional/behavioral functioning, whereas pessimism was related to poorer mental health and general behavior, and greater impact on the family., Conclusions: Optimism and pessimism appear to be differentially related to certain aspects of children's HRQL, and should be investigated separately in relation to these outcomes.

Background: Streptococcus pneumoniae is a leading cause of vaccine-preventable disease worldwide. Pneumococcal protein antigens are currently under study as components of potential vaccines that offer protection against multiple serotypes. We have therefore characterized T cell pneumococcal immunity acquired through asymptomatic carriage., Methods: Peripheral blood mononuclear cells from 40 healthy Gambian adults were stimulated with supernatants derived from S. pneumoniae strain (D39), 2 isogenic mutant strains lacking either pneumolysin or choline binding protein A, and recombinant pneumolysin. Immune responses were measured by cellular proliferation and by interleukin-10 (IL-10) and interferon-gamma (IFN-gamma) enzyme-linked immunosorbent spot and bioplex cytokine assays. Nasopharyngeal swabs were cultured to determine carriage rates., Results: S. pneumoniae nasopharyngeal carriage was detected in 60% of individuals. Both effector and resting (or central) CD4(+) T cell memory were frequently present to a range of pneumococcal antigens. However, the level of the effector memory response did not relate to current nasopharyngeal carriage. Pneumolysin was not immunodominant in these T cell responses but induced a distinct proinflammatory profile (high IFN-gamma, IL-12[p40], and L-17 levels and low IL-10 and IL-13 levels)., Conclusions: In this population, T cell-mediated immunological memory potentially capable of pathogen clearance and immune surveillance is common but is not associated with the absolute interruption of pneumococcal carriage. How this naturally acquired immune memory influences pneumococcal vaccine efficacy remains to be determined.

Objective: The present study used a case-crossover design to investigate the association of caregiver alcohol consumption and supervision to children's injury occurrence and severity., Method: A community sample of 170 mothers of toddlers was interviewed biweekly about their children's daily injuries for a period of 6 months., Results: Proximal caregiver-reported alcohol use predicted higher likelihood of injury occurrence and higher injury severity, whereas caregiver-reported supervision predicted lower likelihood of injury occurrence and lower injury severity., Conclusion: Even at low levels, proximal caregiver alcohol use may contribute to higher risk for childhood injuries and more severe injuries. The combined effect of supervision and drinking on injury likelihood warrants further exploration.

Background: Nasopharyngeal carriage of meningococcus or related species leads to protective immunity in adolescence or early adulthood. This natural immunity is associated with mucosal and systemic T cell memory. Whether parenteral Neisseria meningitidis serogroup B (MenB) vaccination influences natural mucosal immunity is unknown., Objectives: To determine whether parenteral MenB vaccination affects mucosal immunity in young adults and whether this immunity differs from that induced in the blood., Methods: Otherwise healthy volunteers were immunized with MenB outer membrane vesicle vaccine before and after routine tonsillectomy. Mucosal and systemic immunity were assessed in 9 vaccinees and 12 unvaccinated control subjects by measuring mononuclear cell proliferation, cytokine production, Th1/Th2 surface marker expression, and antibody to MenB antigens., Results: Parenteral vaccination induced a marked increase in systemic T cell immunity against MenB and a Th1 bias. In contrast, although mucosal T cell proliferation in response to MenB neither increased nor decreased following vaccination, mononuclear cell interferon gamma, interleukin (IL)-5, and IL-10 production increased, and the Th1/Th2 profile lost its Th1 bias., Conclusions: Parenteral MenB vaccination selectively reprograms preexisting naturally acquired mucosal immunity. As new-generation protein-based MenB vaccine candidates undergo evaluation, the impact of these vaccines on mucosal immunity in both adults and children will need to be addressed.

Objective: To examine how maternal and child characteristics interact to moderate injury rate and injury severity for young children., Methods: In this study, 149 mothers reported their toddlers' injuries over a 6-month period during biweekly interviews. Mothers completed questionnaires assessing parenting behaviors, psychological characteristics, and their children's injury-relevant behaviors., Results: Maternal locus of control was found to moderate the association between children's risky behavior and child injury rate. Specifically, an external locus of control was associated with increased child injury rate for high-risk but not for low-risk children., Conclusion: These findings illuminate the potential importance of parental locus of control in moderating high-risk injury-relevant behavior.

We sought to determine whether palatine tonsils (PTs) harbor naturally acquired influenza-specific T cell immunity and whether routine parenteral immunization with influenza vaccine influences mucosal and systemic T cell reactivity. We demonstrate that tonsillar and peripheral blood mononuclear cells (PBMCs) proliferate strongly to influenza antigens, suggesting that naturally acquired immunity exists within both the mucosal and systemic compartments. Influenza vaccination induced significantly stronger T cell responses in both PTs and blood, in addition to increasing titers of anti-influenza antibodies in serum and saliva. More-rapid proliferative responses of PTs after vaccination were associated with a shift from a response involving both CD45RA+ and CD45RO+ T cells to an entirely CD45RO+-dependent response. Interestingly, the ratio of interferon- gamma to interleukin-5 was dramatically higher in cultures of PT T cells responding to influenza than in PBMCs. Our data indicate that parenteral influenza vaccination influences both mucosal and systemic naturally acquired T cell immunity.

Members of the Emx homeobox gene class are expressed during embryogenesis in the brain and/or other head structures of phylogenetically diverse phyla. Here, we describe sequence, genomic structure, and molecular phylogenetic analysis of a cephalochordate (amphioxus) Emx class gene termed AmphiEmxA. The genomic structure of AmphiEmxA is very similar to that of vertebrate Emx genes, with two conserved intron sites. The Drosophila homolog empty spiracles (ems) has just one intron, which may be shared with chordates; the other has been secondarily lost in this Drosophila gene and in a cnidarian Emx-related gene. We identify a highly conserved peptide motif close to the amino terminus of Emx proteins, demonstrate its similarity to a sequence found in a variety of transcription factors, and argue that it arose through convergent evolution in homeobox and forkhead genes. Finally, our molecular phylogenetic analysis strongly supports the presence of a single Emx gene in the ancestor of chordates and gene duplication along the vertebrate lineage.

Helicobacter pylori NCTC 11637 produces a water-insoluble biofilm when grown under defined conditions with a high carbon:nitrogen ratio in continuous culture and in 10% strength Brucella broth supplemented with 3 g l-1 glucose. Biofilm accumulated at the air/liquid interface of the culture. Light microscopy of frozen sections of the biofilm material showed few bacterial cells in the mass of the biofilm. The material stained with periodic acid Schiff's reagent. Fucose, glucose, galactose, and glycero-manno-heptose, N-acetylglucosamine and N-acetylmuramic acid were identified in partially purified and in crude material, using gas chromatography and mass spectrometry. The sugar composition strongly indicates the presence of a polysaccharide as a component of the biofilm material. Antibodies (IgG) to partially purified material were found in both sero-positive and sero-negative individuals. Treatment of the biofilm material with periodic acid reduced or abolished immunoreactivity. Treatment with 5 mol l-1 urea at 100 degrees C and with phenol did not remove antigenic recognition by patient sera. The production of a water-insoluble biofilm by H. pylori may be important in enhancing resistance to host defence factors and antibiotics, and in microenvironmental pH homeostasis facilitating the growth and survival of H. pylori in vivo.

Immune responses were assessed after intranasal immunization of mice with a mixture of herpes simplex virus type 1 (HSV-1) glycoproteins with cholera toxin and its B subunit as adjuvant. Antigen-specific serum antibodies, which were largely IgG with IgG1 the major subclass, neutralized virus in vitro with a titer equivalent to that elicited by active infection. Significant levels of antigen-specific IgA were found in mucosal fluids of the eye as well as the vagina. Lymphocytes from draining lymph nodes showed secondary proliferative responses when cultured with HSV-1 in vitro, in immunized mice only, with the production of interleukin-2, interferon-gamma, interleukin-4, and interleukin-5. After ocular challenge, immunized mice were protected against the development of severe eye disease, zosteriform spread, or encephalitis, whereas the incidence of clinical symptoms in mock-immunized mice was 83%, 74%, and 52%, respectively. Finally, the incidence of latency was reduced from 88% to 13% after intranasal immunization.

We report the genomic organization and deduced protein sequence of a cephalochordate member of the Otx homeobox gene family (AmphiOtx) and show its probable single-copy state in the genome. We also present molecular phylogenetic analysis indicating that there was single ancestral Otx gene in the first chordates which was duplicated in the vertebrate lineage after it had split from the lineage leading to the cephalochordates. Duplication of a C-terminal protein domain has occurred specifically in the vertebrate lineage, strengthening the case for a single Otx gene in an ancestral chordate whose gene structure has been retained in an extant cephalochordate. Comparative analysis of protein sequences and published gene expression patterns suggest that the ancestral chordate Otx gene had roles in patterning the anterior mesendoderm and central nervous system. These roles were elaborated following Otx gene duplication in vertebrates, accompanied by regulatory and structural divergence, particularly of Otx1 descendant genes.

The factors which control whether an asymptomatic or symptomatic infection in the skin follows reactivation of herpes simplex virus (HSV) in the sensory ganglia remain unclear. Xylene, retinoic acid and dimethylsuphoxide (DMSO) all stimulate similar levels of virus reactivation in the ganglia of latently infected mice, yet give rise to high, moderate and very low incidences of clinical skin disease, respectively. This observation suggests that the chemicals may be capable of affecting the local microenvironment of the skin. In the present study we have investigated the effects of xylene, retinoic acid and DMSO on Langerhans cell (LC) phenotype and function. The results show that none of the chemicals inhibit the phenotypic maturation of Langerhans cells in vitro. However, DMSO induced a dramatic elevation in class II MHC expression on Langerhans cells. In addition, fewer antigen-bearing dendritic cells (DC) were evident in the lymph nodes if xylene was administered to the skin prior to challenge with the contact sensitizer, FITC. None of the chemicals inhibited the accumulation of DC in the lymph nodes after such an antigen-challenge, suggesting that xylene was affecting not migration, but antigen uptake. The inhibition of antigen uptake by xylene together with the activation of LC in terms of class II expression by DMSO may explain, in part, the relative abilities of these chemicals to allow the establishment of recurrent HSV disease in the skin.

The stability of levofloxacin in 10 commonly used infusion fluids was studied. Levofloxacin 25-mg/mL injection was diluted to 0.5 and 5 mg/mL in each of the following i.v. infusion fluids: 0.9% sodium chloride injection, 5% dextrose injection, 5% dextrose and 0.9% sodium chloride injection, 5% dextrose and lactated Ringer's injection, 5% sodium bicarbonate injection, Plasma-Lyte 56 and 5% dextrose injection, 5% dextrose and 0.45% sodium chloride and 0.15% potassium chloride injection, 1/6 M sodium lactate injection, sterile water for injection, and 20% mannitol injection. Ten polyvinyl chloride bags were prepared for each solution; two were stored for 3 days at 25 degrees C, two for 7 days at 5 degrees C, two for 14 days at 5 degrees C, two for 13 weeks at -20 degrees C followed by 14 days at 5 degrees C, and two for 26 weeks at -20 degrees C, all in the dark. The solutions were visually examined, tested for turbidity and particulate matter, and subjected to stability-indicating high-performance liquid chromatography; solution pH was determined. Levofloxacin was stable in and compatible with all but two of the diluents tested. Precipitation occurred under all conditions in 20% mannitol injection for the 0.5-mg/mL levofloxacin concentration and after storage for 13 weeks at -20 degrees C for the 5-mg/mL concentration. Levofloxacin 0.5 mg/mL in 5% sodium bicarbonate injection formed a precipitate when stored at -20 degrees C for 13 weeks and beyond. Levofloxacin 0.5 and 5 mg/mL was compatible with and stable in 8 of the 10 infusion fluids studied.

As in HIV infection of humans, cats infected with FIV are particularly susceptible to secondary infection by opportunistic pathogens, suggesting an impaired ability to elicit an effective immune response against foreign antigens. In order to investigate the development of immunity in FIV-infected cats, we have used an autologous culture system to directly measure priming of naive CD4+ T cells to soluble protein antigen, in vitro. Using this assay, we showed previously that cats infected with FIV for several months had significantly reduced primary proliferative responses. We have now examined cats before infection, and at varying times after infection with FIV, to determine how soon after infection this defect in T cell priming was evident, compared with other quantitative and qualitative measurements of lymphocyte function. Our results showed a progressive decline in immune function in asymptomatic cats during the acute stage of infection with FIV. Primary T cell responses were most sensitive and a significant reduction in proliferation of naive T cells to foreign antigen occurred 5 weeks after infection, despite normal blastogenesis to T cell mitogens and normal CD4+/CD8+ ratios at these times. Whilst lymphocyte proliferation to T cell mitogens was unaffected throughout, a significant reduction in proliferation to a B cell mitogen occurred from week 8 onwards. CD4+/CD8+ ratios fell significantly from week 13 onwards, and proliferation of the memory T cell population to a recall antigen was significantly impaired later, from week 19 onwards. The defect in the priming of naive T cells to foreign antigen early after infection may be important in determining susceptibility to secondary infections.