Human blood CXCR5(+)CD4(+) T cells are counterparts of T follicular cells and contain specific subsets that differentially support antibody secretion

Although a fraction of human blood memory CD4(+) T cells expresses chemokine (C-X-C motif) receptor 5 (CXCR5), their relationship to T follicular helper (Tfh) cells is not well established. Here we show that human blood CXCR5(+)CD4(+) T cells share functional properties with Tfh cells and appear to represent their circulating memory compartment. Blood CXCR5(+)CD4(+) T cells comprised three subsets: T helper 1 (Th1), Th2, and Th17 cells. Th2 and Th17 cells within CXCR5(+), but not within CXCR5(-), compartment efficiently induced naive B cells to produce immunoglobulins via interleukin-21 (IL-21). In contrast, Th1 cells from both CXCR5(+) and CXCR5(-) compartments lacked the capacity to help B cells. Patients with juvenile dermatomyositis, a systemic autoimmune disease, displayed a profound skewing of blood CXCR5(+) Th cell subsets toward Th2 and Th17 cells. Importantly, the skewing of subsets correlated with disease activity and frequency of blood plasmablasts. Collectively, our study suggests that an altered balance of Tfh cell subsets contributes to human autoimmunity.

Induction of ICOS+CXCR3+CXCR5+ TH cells correlates with antibody responses to influenza vaccination

Seasonal influenza vaccine protects 60 to 90% of healthy young adults from influenza infection. The immunological events that lead to the induction of protective antibody responses remain poorly understood in humans. We identified the type of CD4+ T cells associated with protective antibody responses after seasonal influenza vaccinations. The administration of trivalent split-virus influenza vaccines induced a temporary increase of CD4+ T cells expressing ICOS, which peaked at day 7, as did plasmablasts. The induction of ICOS was largely restricted to CD4+ T cells coexpressing the chemokine receptors CXCR3 and CXCR5, a subpopulation of circulating memory T follicular helper cells. Up to 60% of these ICOS+CXCR3+CXCR5+CD4+ T cells were specific for influenza antigens and expressed interleukin-2 (IL-2), IL-10, IL-21, and interferon-γ upon antigen stimulation. The increase of ICOS+CXCR3+CXCR5+CD4+ T cells in blood correlated with the increase of preexisting antibody titers, but not with the induction of primary antibody responses. Consistently, purified ICOS+CXCR3+CXCR5+CD4+ T cells efficiently induced memory B cells, but not naïve B cells, to differentiate into plasma cells that produce influenza-specific antibodies ex vivo. Thus, the emergence of blood ICOS+CXCR3+CXCR5+CD4+ T cells correlates with the development of protective antibody responses generated by memory B cells upon seasonal influenza vaccination.

Patient satisfaction with health care decisions: the satisfaction with decision scale

Patient satisfaction measures have previously addressed satisfaction with medical care, satisfaction with providers, and satisfaction with outcomes, but not satisfaction with the health care decision itself. As patients become more involved in health care decisions, it is important to understand specific dynamics of the decision itself. The Satisfaction with Decision (SWD) scale measures satisfaction with health care decisions. It was developed in the context of postmenopausal hormone-replacement therapy decisions. The six-item scale has excellent reliability (Cronbach's alpha = 0.86). Discriminant validity, tested by performing principal-components analysis of items pooled from the SWD scale and two conceptually related measures, was good. Correlation of the SWD scale with measures of satisfaction with other aspects of the decision-making process showed the SWD scale was correlated most highly (0.64) with "decisional confidence," and least with "desire to participate in health care decisions" and "satisfaction with provider." The SWD scale predicts decision certainty in this study. Use in an independent study showed that the SWD scale was correlated with the likelihood of patients' intentions to get a flu shot. Further investigation in relation to other health decisions will establish the utility of the SWD scale as an outcome measure.

Phenotype and functions of memory Tfh cells in human blood

Our understanding of the origin and functions of human blood CXCR5(+) CD4(+) T cells found in human blood has changed dramatically in the past years. These cells are currently considered to represent a circulating memory compartment of T follicular helper (Tfh) lineage cells. Recent studies have shown that blood memory Tfh cells are composed of phenotypically and functionally distinct subsets. Here, we review the current understanding of human blood memory Tfh cells and the subsets within this compartment. We present a strategy to define these subsets based on cell surface profiles. Finally, we discuss how increased understanding of the biology of blood memory Tfh cells may contribute insight into the pathogenesis of autoimmune diseases and the mode of action of vaccines.

Human dendritic cells induce the differentiation of interleukin-21-producing T follicular helper-like cells through interleukin-12

T follicular helper (Tfh) cells help development of antibody responses via interleukin-21 (IL-21). Here we show that activated human dendritic cells (DCs) induced naive CD4(+) T cells to become IL-21-producing Tfh-like cells through IL-12. CD4(+) T cells primed with IL-12 induced B cells to produce immunoglobulins in a fashion dependent on IL-21 and inducible costimulator (ICOS), thus sharing fundamental characteristics with Tfh cells. The induction of Tfh-like cells by activated DCs was inhibited by neutralizing IL-12. IL-12 induced two different IL-21-producers: IL-21(+)IFN-gamma(+)T-bet(+) Th1 cells and IL-21(+)IFN-gamma(-)T-bet(-) non-Th1 cells, in a manner dependent on signal transducer and activator of transcription 4 (STAT4). IL-12 also regulated IL-21 secretion by memory CD4(+) T cells. Thus, IL-12 produced by activated DCs regulates antibody responses via developing IL-21-producing Tfh-like cells and inducing IL-21 secretion from memory CD4(+) T cells. These data suggest that the developmental pathway of Tfh cells differs between mice and humans, which have considerable implications for vaccine development.

Video-based versus paper-and-pencil method of assessment in situational judgment tests: subgroup differences in test performance and face validity perceptions

On the basis of a distinction between test content and method of testing, the present study examined several conceptually and practically important effects relating race, reading comprehension, method of assessment, face validity perceptions, and performance on a situational judgement test using a sample of 241 psychology undergraduates (113 Blacks and 128 Whites). Results showed that the Black-White differences in situational judgment test performance and face validity reactions to the test were substantially smaller in the video-based method of testing than in the paper-and-pencil method. The Race x Method interaction effect on test performance was attributable to differences in reading comprehension and face validity reactions associated with race and method of testing. Implications of the findings were discussed in the context of research on adverse impact and examinee test reactions.

Regulation of human helper T cell subset differentiation by cytokines

Since the discovery of Th1 and Th2 cells in the late 1980s, the family of effector CD4(+) helper T (Th) cell subsets has expanded. The differentiation of naïve CD4(+) T cells is largely determined when they interact with dendritic cells (DCs) in lymphoid organs, and cytokines play a major role in the regulation of Th differentiation in the early stages. Recent studies show that the developmental mechanism of certain Th subsets is not fully shared between mice and humans. Here we will review recent discoveries on the roles of cytokines in the regulation of Th differentiation in humans, and discuss the differences between mice and humans in the developmental mechanisms of several Th subsets, including Th17 cells and T follicular helper (Tfh) cells. We propose that the differentiation of human Th subsets is largely regulated by the three cytokines, IL-12, IL-23, and TGF-β.

Interindividual differences in intraindividual changes in proactivity during organizational entry: a latent growth modeling approach to understanding newcomer adaptation

Intraindividual change over time is the essence of the change phenomenon hypothesized to occur in the individual newcomer adaptation process. Many important adaptation questions cannot be answered without an adequate conceptualization and assessment of intraindividual change. Using a latent growth modeling approach to data collected from 146 doctoral program newcomers over 4 repeated measurements spaced at 1-month intervals, the authors explicitly modeled interindividual differences in intraindividual changes in newcomer proactivities (information seeking, relationship building) and proximal adaptation outcomes (task mastery, role clarity, social integration) during organizational entry. Results indicated that changes in proactivity may be related to newcomer characteristics and adaptation outcomes in interesting ways that have not been previously examined.

OX40 Ligand Contributes to Human Lupus Pathogenesis by Promoting T Follicular Helper Response

Increased activity of T follicular helper (Tfh) cells plays a major pathogenic role in systemic lupus erythematosus (SLE). However, the mechanisms that cause aberrant Tfh cell responses in SLE remain elusive. Here we showed the OX40 ligand (OX40L)-OX40 axis contributes to the aberrant Tfh response in SLE. OX40L was expressed by myeloid antigen-presenting cells (APCs), but not B cells, in blood and in inflamed tissues in adult and pediatric SLE patients. The frequency of circulating OX40L-expressing myeloid APCs positively correlated with disease activity and the frequency of ICOS(+) blood Tfh cells in SLE. OX40 signals promoted naive and memory CD4(+) T cells to express multiple Tfh cell molecules and were sufficient to induce them to become functional B cell helpers. Immune complexes containing RNA induced OX40L expression on myeloid APCs via TLR7 activation. Our study provides a rationale to target the OX40L-OX40 axis as a therapeutic modality for SLE.

Harnessing human dendritic cell subsets for medicine

Immunity results from a complex interplay between the antigen-non-specific innate immune system and the antigen-specific adaptive immune system. The cells and molecules of the innate system employ non-clonal recognition receptors including lectins, Toll-like receptors, NOD-like receptors, and helicases. B and T lymphocytes of the adaptive immune system employ clonal receptors recognizing antigens or their derived peptides in a highly specific manner. An essential link between innate and adaptive immunity is provided by dendritic cells (DCs). DCs can induce such contrasting states as immunity and tolerance. The recent years have brought a wealth of information on the biology of DCs revealing the complexity of this cell system. Indeed, DC plasticity and subsets are prominent determinants of the type and quality of elicited immune responses. In this article, we summarize our recent studies aimed at a better understanding of the DC system to unravel the pathophysiology of human diseases and design novel human vaccines.

A recessive C-terminal Jervell and Lange-Nielsen mutation of the KCNQ1 channel impairs subunit assembly

The LQT1 locus (KCNQ1) has been correlated with the most common form of inherited long QT (LQT) syndrome. LQT patients suffer from syncopal episodes and high risk of sudden death. The KCNQ1 gene encodes KvLQT1 alpha-subunits, which together with auxiliary IsK (KCNE1, minK) subunits form IK(s) K(+) channels. Mutant KvLQT1 subunits may be associated either with an autosomal dominant form of inherited LQT, Romano-Ward syndrome, or an autosomal recessive form, Jervell and Lange-Nielsen syndrome (JLNS). We have identified a small domain between residues 589 and 620 in the KvLQT1 C-terminus, which may function as an assembly domain for KvLQT1 subunits. KvLQT1 C-termini do not assemble and KvLQT1 subunits do not express functional K(+) channels without this domain. We showed that a JLN deletion-insertion mutation at KvLQT1 residue 544 eliminates important parts of the C-terminal assembly domain. Therefore, JLN mutants may be defective in KvLQT1 subunit assembly. The results provide a molecular basis for the clinical observation that heterozygous JLN carriers show slight cardiac dysfunctions and that the severe JLNS phenotype is characterized by the absence of KvLQT1 channel.

Chromatin Accessibility Landscape of Cutaneous T Cell Lymphoma and Dynamic Response to HDAC Inhibitors

Here, we define the landscape and dynamics of active regulatory DNA in cutaneous T cell lymphoma (CTCL) by ATAC-seq. Analysis of 111 human CTCL and control samples revealed extensive chromatin signatures that distinguished leukemic, host, and normal CD4⁺ T cells. We identify three dominant patterns of transcription factor (TF) activation that drive leukemia regulomes, as well as TF deactivations that alter host T cells in CTCL patients. Clinical response to histone deacetylase inhibitors (HDACi) is strongly associated with a concurrent gain in chromatin accessibility. HDACi causes distinct chromatin responses in leukemic and host CD4⁺ T cells, reprogramming host T cells toward normalcy. These results provide a foundational framework to study personal regulomes in human cancer and epigenetic therapy.

An educational intervention as decision support for menopausal women

The purpose of this study was to develop and test a decision support intervention (DSI) to assist women to make and act on informed decisions that are consistent with their values in the area of menopause and hormone replacement therapy (HRT). Mode and intensity of intervention were tested in midlife women (N = 248), randomly assigned to one of three intervention formats: written information only, guided discussion, or personalized decision exercise. Data were collected over 12 months. Knowledge, decisional conflict, satisfaction with health care provider, and self-efficacy improved following intervention and were maintained for 12 months for all groups. Women's adherence to their own plans over 12 months was 59% (exercise), 76% (calcium intake), and 89% (HRT). Carefully written information is effective in promoting knowledge, adherence, and satisfaction among well-educated, interested women. It was concluded that women can understand complex information, including tradeoffs regarding treatment options. Women will adhere to their own plans, suggesting that consumer rather than provider plans may be the more appropriate gold standard for measuring adherence.

Incremental validation of situational judgment tests

Using 3 different samples, the authors assessed the incremental validity of situational judgment inventories (SJIs), relative to job knowledge, cognitive ability, job experience, and conscientiousness, in the prediction of job performance. The SJI was a valid predictor in all 3 samples and incrementally so in 2 samples. Relative to the other predictors, SJI's partial correlation with performance, controlling for the other 4 predictors, was superior in most comparisons. Subgroup differences on the SJI also appear to be less than those for cognitive ability and job knowledge, but greater than differences in conscientiousness. The SJI should prove to be a valuable additional measure in the prediction of job performance, but several additional areas of research are suggested.

IL-7 induces immunological improvement in SIV-infected rhesus macaques under antiviral therapy

Despite efficient antiretroviral therapy (ART), CD4+ T cell counts often remain low in HIV-1-infected patients. This has led to IL-7, a crucial cytokine involved in both thymopoiesis and peripheral T cell homeostasis, being suggested as an additional therapeutic strategy. We investigated whether recombinant simian IL-7-treatment enhanced the T cell renewal initiated by ART in rhesus macaques chronically infected with SIVmac251. Six macaques in the early chronic phase of SIV infection received antiretroviral treatment. Four macaques also received a 3-wk course of IL-7 injections. Viral load was unaffected by IL-7 treatment. IL-7 treatment increased the number of circulating CD4+ and CD8+ memory T cells expressing activation (HLA-DR+, CD25+) and proliferation (Ki-67+) markers. It also increased naive (CD45RAbrightCD62L+) T cell counts by peripheral proliferation and enhanced de novo thymic production. The studied parameters returned to pretreatment values by day 29 after the initiation of treatment, concomitantly to the appearance of anti-IL-7 neutralizing Abs, supporting the need for a nonimmunogenic molecule for human treatment. Thus, IL-7, which increases T cell memory and de novo renewal of naive T cells may have additional benefits in HIV-infected patients receiving ART.

Reactions to cognitive ability tests: the relationships between race, test performance, face validity perceptions, and test-taking motivation

The relationships among race, face validity perceptions, test-taking motivation, and test performance on a cognitive ability test were examined. Undergraduates completed 2 parallel cognitive ability tests and a test reactions measure. Results showed that test-taking motivation was related positively to subsequent performance on a parallel test even after the effects of race and performance on the first test were controlled. The effect of race on subsequent test performance was found to be mediated partially by motivation that provided evidence that some portion of the Black-White difference in test performance may be explained through differences in test-taking motivation. Results also indicated that Black-White differences in face validity perceptions of the test may be a function of Black-White differences in test performance. Face validity perceptions of the test affected subsequent performance on the parallel test but only indirectly through test-taking motivation.

Understanding pretest and posttest reactions to cognitive ability and personality tests

To understand the nature of test reactions and their relationship to test performance, the relationships among belief in tests, pretest reactions, test performance, and posttest reactions were modeled for cognitive ability and personality tests. Results from structural equation models that were fitted to responses from 197 undergraduate examinees supported the hypothesized relationships. On the cognitive ability test, pretest reactions affected test performance and mediated the relationship between belief in tests and test performance. Test performance affected posttest reactions even after taking into account the effect of pretest reactions. On the personality test, belief in tests affected pretest and posttest reactions, but the three variables were unrelated to test performance (Conscientiousness scores). Conceptual, methodological, and practical implications of the findings are discussed in the context of research on test reactions and test performance.

Calcium solubility of dental enamel following sub-ablative Er:YAG and Er:YSGG laser irradiation in vitro

BACKGROUND AND OBJECTIVE

The objective of the present study was to investigate the effect of sub-ablative Er:YAG (lambda = 2.94 microm) and Er:YSGG (lambda = 2.79 microm) laser radiation on the acid solubility of dental enamel. The influence of fluoride application prior to laser irradiation was additionally evaluated.

STUDY DESIGN/MATERIALS AND METHODS

To this end, 294 enamel specimens were prepared from bovine teeth and divided into 14 groups of 21 specimens each. The enamel samples were irradiated in their groups with the Er:YAG and the Er:YSGG laser, using energy densities of 4, 6, and 8 J/cm(2) in each case. Irradiation was additionally repeated in the same way on specimens, which had previously been immersed in 1% sodium fluoride solution for 15 minutes. One group was left untreated and served as a control group. A further group was not irradiated, but only immersed in the 1% fluoride solution for 15 minutes. The enamel specimens were demineralised for 24 hours in an acetate buffer solution. The calcium content in the demineralisation solution was subsequently determined with the aid of atomic absorption spectrometry.

RESULTS

The results indicate a decline in calcium solubility after laser irradiation. Compared to the control group, a 20% lower calcium content was detected in the demineralisation solution after irradiation with the Er:YSGG laser at 8 J/cm(2). The difference between the laser-irradiated groups and the untreated control group was, however, not statistically significant. A significantly lower calcium content was found in the demineralisation solution after fluoridation of the specimens. Additional laser radiation had no further effect on this result.

CONCLUSIONS

In summary, it can be stated that, although the erbium laser wavelengths apparently have the potential to increase acid resistance, their application solely for caries prevention would not appear to be sensible under the prevailing conditions.

Cyclosporin in the treatment of patients with atopic eczema - a systematic review and meta-analysis

OBJECTIVE

To systematically assess the effectiveness of systemic cyclosporin in patients with severe atopic eczema.

STUDY DESIGN

Systematic review and meta-analysis of controlled and uncontrolled trials. Electronic (MEDLINE, Cochrane databases) and hand search of published work. Independent standardized assessment of eligibility and data abstraction by two reviewers.

METHODS

For the qualitative review data on study design, study population, methodology, results, tolerability and methodological quality was independently extracted by two reviewers. Qualitatively homogeneous studies were pooled using a random-effects model. The mean relative change in objective disease severity was chosen as the main outcome measure for the quantitative analysis. Publication bias was explored by regressing treatment effect on sample size. Sensitivity analysis included meta-regression of study-specific covariates (inclusion of children, study type, concomitant topical therapy, study quality).

RESULTS

Fifteen studies including 602 patients met the eligibility criteria. In all studies analysed, cyclosporin consistently decreased the severity of atopic eczema. Twelve studies appeared homogeneous enough to be pooled. After 2 weeks of treatment we found a dose-related response with a pooled mean decrease in disease severity of 22% (95%-CI 8-36%) under low-dose cyclosporin ( 3 mg/kg) and 40% (95%-CI 29-51%) at dosages >or=4 mg/kg. After 6-8 weeks the relative effectiveness was 55% (95%-CI 48-62%).

CONCLUSIONS

Due to evidence of publication bias the quantitative results need to be interpreted with caution. Effectiveness of cyclosporin is similar in adults and children, but tolerability might be better in children. As data to adequately evaluate the long-term effectiveness and safety of cyclosporin in patients with atopic eczema are unavailable, long-term registries are encouraged.

Harnessing human dendritic cell subsets to design novel vaccines

Dendritic cells (DCs) orchestrate a repertoire of immune responses that endow resistance to infection and tolerance to self. DC plasticity and subsets are prominent determinants of the quality of elicited immune responses. Different DC subsets display different receptors and surface molecules and express different sets of cytokines/chemokines, all of which lead to distinct immunological outcomes. Recent findings on human DC subsets and their functional specialization have provided insights for the design of novel human vaccines.

Patient decision support intervention: increased consistency with decision analytic models

BACKGROUND

Patient Decision Support (PDS) tools assist patients in using medical evidence to make choices consistent that are with their values and in using evidence about consequences of medical alternatives.

OBJECTIVE

To evaluate a PDS intervention for perimenopausal hormone replacement therapy. We assessed the impact of the PDS on (1) consistency between the decision to take estrogen replacement therapy (ERT) or progesterone/estrogen replacement therapy (PERT) and the expected utility of treatment and (2) likelihood to take ERT and PERT pre- and postintervention.

DESIGN

Content of the PDS was standardized. Randomized trial of three intensities of intervention: (1) brochure; (2) lecture/discussion; and (3) active decision support.

SUBJECTS

Participants were perimenopausal community volunteers between the ages of 40 and 65 (n = 248).

MEASURES

(1) Consistent with values (correlation between expected utility (EU) and likelihood of taking hormones); and (2) Likelihood to take hormone replacement therapy.

RESULTS

(1) The brochure group was less consistent with the decision analytic model than the lecture/discussion and active decision support groups. (2) Influence on decisions: PDS tools increased the number of women certain about whether or not to take hormones. There were no differences among experimental groups. Of 99 women uncertain about ERT pre-PDS, 65% changed. Twenty-one (32%) decided against ERT and 44 (68%) decided for ERT. (3) More intensive interventions produced modest gains in a normative direction.

CONCLUSIONS

PDSs using any of 3 formats reduce uncertainty and assist women to make informed decisions. Increased consistency with decision analytic models appears to be driven by better estimates of likelihood of outcomes.

Positive regulation of CXCR4 expression and signaling by interleukin-7 in CD4+ mature thymocytes correlates with their capacity to favor human immunodeficiency X4 virus replication

The emergence of X4 human immunodeficiency virus type 1 (HIV-1) variants in infected individuals is associated with poor prognosis. One of the possible causes of this emergence might be the selection of X4 variants in some specific tissue compartment. We demonstrate that the thymic microenvironment favors the replication of X4 variants by positively modulating the expression and signaling of CXCR4 in mature CD4(+) CD8(-) CD3(+) thymocytes. Here, we show that the interaction of thymic epithelial cells (TEC) with these thymocytes in culture induces an upregulation of CXCR4 expression. The cytokine secreted by TEC, interleukin-7 (IL-7), increases cell surface expression of CXCR4 and efficiently overcomes the downregulation induced by SDF-1 alpha, also produced by TEC. IL-7 also potentiates CXCR4 signaling, leading to actin polymerization, a process necessary for virus entry. In contrast, in intermediate CD4(+) CD8(-) CD3(-) thymocytes, the other subpopulation known to allow virus replication, TEC or IL-7 has little or no effect on CXCR4 expression and signaling. CCR5 is expressed at similarly low levels in the two thymocyte subpopulations, and neither its expression nor its signaling was modified by the cytokines tested. This positive regulation of CXCR4 by IL-7 in mature CD4(+) thymocytes correlates with their high capacity to favor X4 virus replication compared with intermediate thymocytes or peripheral blood mononuclear cells. Indeed, we observed an enrichment of X4 viruses after replication in thymocytes initially infected with a mixture of X4 (NL4-3) and R5 (NLAD8) HIV strains and after the emergence of X4 variants from an R5 primary isolate during culture in mature thymocytes.

Blood Tfh cells come with colors

Blood CXCR5⁺ CD4⁺ T cells share phenotypic and functional similarities with T follicular helper cells. Studies by He et al. (2013) and Locci et al. (2013) in this issue of Immunity provide insight into their ontogeny and functionally distinct subsets.

The Use Of Analysis Of Covariance Structures To Assess Beta And Gamma Change

Detection of alpha, beta, and gamma change in assessments of organizational intervention have been problematic because of lack of clear definition of beta and gamma change and/or methods to assess such change. The present paper applies an analysis of covariance structures to this problem using pre and post employment responses to a questionnaire assessing human needs. An analysis of data transformed in a manner consistent with theoretical definitions of beta change indicated the presence of such change and further supported the use of the procedure.