Pembrolizumab versus placebo as post-nephrectomy adjuvant therapy for clear cell renal cell carcinoma (KEYNOTE-564): 30-month follow-up analysis of a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial

BACKGROUND

The first interim analysis of the KEYNOTE-564 study showed improved disease-free survival with adjuvant pembrolizumab compared with placebo after surgery in patients with clear cell renal cell carcinoma at an increased risk of recurrence. The analysis reported here, with an additional 6 months of follow-up, was designed to assess longer-term efficacy and safety of pembrolizumab versus placebo, as well as additional secondary and exploratory endpoints.

METHODS

In the multicentre, randomised, double-blind, placebo-controlled, phase 3 KEYNOTE-564 trial, adults aged 18 years or older with clear cell renal cell carcinoma with an increased risk of recurrence were enrolled at 213 hospitals and cancer centres in North America, South America, Europe, Asia, and Australia. Eligible participants had an Eastern Cooperative Oncology Group performance status of 0 or 1, had undergone nephrectomy 12 weeks or less before randomisation, and had not received previous systemic therapy for advanced renal cell carcinoma. Participants were randomly assigned (1:1) via central permuted block randomisation (block size of four) to receive pembrolizumab 200 mg or placebo intravenously every 3 weeks for up to 17 cycles. Randomisation was stratified by metastatic disease status (M0 vs M1), and the M0 group was further stratified by ECOG performance status and geographical region. All participants and investigators involved in study treatment administration were masked to the treatment group assignment. The primary endpoint was disease-free survival by investigator assessment in the intention-to-treat population (all participants randomly assigned to a treatment). Safety was assessed in the safety population, comprising all participants who received at least one dose of pembrolizumab or placebo. As the primary endpoint was met at the first interim analysis, updated data are reported without p values. This study is ongoing, but no longer recruiting, and is registered with ClinicalTrials.gov, NCT03142334.

FINDINGS

Between June 30, 2017, and Sept 20, 2019, 994 participants were assigned to receive pembrolizumab (n=496) or placebo (n=498). Median follow-up, defined as the time from randomisation to data cutoff (June 14, 2021), was 30·1 months (IQR 25·7-36·7). Disease-free survival was better with pembrolizumab compared with placebo (HR 0·63 [95% CI 0·50-0·80]). Median disease-free survival was not reached in either group. The most common all-cause grade 3-4 adverse events were hypertension (in 14 [3%] of 496 participants) and increased alanine aminotransferase (in 11 [2%]) in the pembrolizumab group, and hypertension (in 13 [3%] of 498 participants) in the placebo group. Serious adverse events attributed to study treatment occurred in 59 (12%) participants in the pembrolizumab group and one (<1%) participant in the placebo group. No deaths were attributed to pembrolizumab.

INTERPRETATION

Updated results from KEYNOTE-564 support the use of adjuvant pembrolizumab monotherapy as a standard of care for participants with renal cell carcinoma with an increased risk of recurrence after nephrectomy.

FUNDING

Merck Sharp & Dohme LLC, a subsidiary of Merck & Co, Inc, Rahway, NJ, USA.

Depression and the risk of autoimmune disease: a nationally representative, prospective longitudinal study

BACKGROUND

Autoimmune diseases are associated with substantial morbidity and mortality, yet the etiology remains unclear. Depression has been implicated as a risk factor for various immune-related disorders but little is known about the risk of autoimmune disease. This study examined the association between depression and the risk of autoimmune disease, and investigated the temporal and dose-response nature of these relationships.

METHOD

A prospective population-based study including approximately 1.1 million people was conducted using linked Danish registries. Depression and autoimmune diseases were diagnosed by physicians and documented in medical records. In total, 145 217 individuals with depression were identified between 1995 and 2012. Survival analyses were used to estimate the relative risk of autoimmune disease among those with, compared to without, depression. Analyses were adjusted for gender, age, and co-morbid mental disorders.

RESULTS

Depression was associated with a significantly increased risk of autoimmune disease [incidence rate ratio (IRR) 1.25, 95% CI 1.19-1.31], compared to those without a history of depression. Results suggest a general increased risk of autoimmune diseases following the onset of depression during first year (IRR 1.29, 95% CI 1.05-1.58), which remained elevated for the ensuing 11 years and beyond (IRR 1.53, 95% CI 1.34-1.76). Findings did not support a dose-response relationship.

CONCLUSIONS

Depression appears to be associated with an increased risk of a range of autoimmune diseases. Depression may play a role in the etiology of certain autoimmune conditions. If replicated, findings could highlight additional clinical implications in the treatment and management of depression. Future studies are needed to investigate the possible social, genetic, and neurobiological underpinnings of these relationships.

Childhood and later life stressors and increased inflammatory gene expression at older ages

Adverse experiences in early life have the ability to "get under the skin" and affect future health. This study examined the relative influence of adversities during childhood and adulthood in accounting for individual differences in pro-inflammatory gene expression in late life. Using a pilot-sample from the Health and Retirement Study (N = 114) aged from 51 to 95, OLS regression models were run to determine the association between a composite score from three proinflammatory gene expression levels (PTGS2, ILIB, and IL8) and 1) childhood trauma, 2) childhood SES, 3) childhood health, 4) adult traumas, and 5) low SES in adulthood. Our results showed that only childhood trauma was found to be associated with increased inflammatory transcription in late life. Furthermore, examination of interaction effects showed that childhood trauma exacerbated the influence of low SES in adulthood on elevated levels of inflammatory gene expression-signifying that having low SES in adulthood was most damaging for persons who had experienced traumatic events during their childhood. Overall our study suggests that traumas experienced during childhood may alter the stress response, leading to more sensitive reactivity throughout the lifespan. As a result, individuals who experienced greater adversity in early life may be at higher risk of late life health outcomes, particularly if adulthood adversity related to SES persists.

Does tumor necrosis factor-alpha (TNF-α) play a role in post-chemotherapy cerebral dysfunction?

Post-chemotherapy treated cancer patients frequently report cognitive difficulties. The biology of this phenomenon is poorly understood, with uncertainty about possible direct toxic effects on the brain, secondary effects from systemic inflammation, host factors/genetic predisposition to cognitive complaints, or hormonal changes influencing cognitive function. To elucidate possible mechanisms associated with post-treatment cognitive dysfunction among breast cancer survivors, in 2007 we established a prospective, longitudinal, observational cohort study of early stage breast cancer patients, recruited at the end of initial treatments (primary treatment exposure included surgery, ± radiation, ± chemotherapy), and prior to the initiation of adjuvant endocrine therapy. We assessed cognitive complaints, neuropsychological (NP) test performance, markers of inflammation, and brain imaging at baseline, 6 months and 12 months after enrollment. In this analysis of data from the first 93 patients enrolled in the cohort study, we focus on the relationship of circulating levels of proinflammatory cytokines to cerebral functioning and chemotherapy exposure. Among the proinflammatory cytokines tested (IL-1 ra, sTNF-RII, CRP, and IL-6) at baseline, only sTNF-RII was increased among chemotherapy exposed patients, with a significant decline in the year after treatment (p=0.003). Higher baseline sTNF-RII in chemotherapy patients was significantly associated with increased memory complaints. In chemotherapy exposed patients, the longitudinal decline in sTNF-RII was significantly correlated with fewer memory complaints over 12 months (r=-0.34, p=0.04). Higher baseline sTNF-RII was also associated with relatively diminished brain metabolism in the inferior frontal cortex (r=-0.55, p=0.02), as well as relatively increased inferior frontal metabolism after 1 year, in chemotherapy-exposed subjects. These preliminary findings suggest that post-chemotherapy increases in TNF-α may be playing an important role in the manifestations of cognitive complaints in breast cancer survivors.

Molecular signatures of peripheral blood mononuclear cells during chronic interferon-α treatment: relationship with depression and fatigue

BACKGROUND

Interferon-alpha (IFN-α) treatment for infectious disease and cancer causes high rates of depression and fatigue, and has been used to investigate the impact of inflammatory cytokines on brain and behavior. However, little is known about the transcriptional impact of chronic IFN-α on immune cells in vivo and its relationship to IFN-α-induced behavioral changes.

METHOD

Genome-wide transcriptional profiling was performed on peripheral blood mononuclear cells (PBMCs) from 21 patients with chronic hepatitis C virus (HCV) either awaiting IFN-α therapy (n=10) or at 12 weeks of IFN-α treatment (n=11).

RESULTS

Significance analysis of microarray data identified 252 up-regulated and 116 down-regulated gene transcripts. Of the up-regulated genes, 2'-5'-oligoadenylate synthetase 2 (OAS2), a gene linked to chronic fatigue syndrome (CFS), was the only gene that was differentially expressed in patients with IFN-α-induced depression/fatigue, and correlated with depression and fatigue scores at 12 weeks (r=0.80, p=0.003 and r=0.70, p=0.017 respectively). Promoter-based bioinformatic analyses linked IFN-α-related transcriptional alterations to transcription factors involved in myeloid differentiation, IFN-α signaling, activator protein-1 (AP1) and cAMP responsive element binding protein/activation transcription factor (CREB/ATF) pathways, which were derived primarily from monocytes and plasmacytoid dendritic cells. IFN-α-treated patients with high depression/fatigue scores demonstrated up-regulation of genes bearing promoter motifs for transcription factors involved in myeloid differentiation, IFN-α and AP1 signaling, and reduced prevalence of motifs for CREB/ATF, which has been implicated in major depression.

CONCLUSIONS

Depression and fatigue during chronic IFN-α administration were associated with alterations in the expression (OAS2) and transcriptional control (CREB/ATF) of genes linked to behavioral disorders including CFS and major depression, further supporting an immune contribution to these diseases.

Genome-wide transcriptional profiling linked to social class in asthma

OBJECTIVES

Low socioeconomic status (SES) is one of the most robust social factors associated with disease morbidity, including more severe asthma in childhood. However, our understanding of the biological processes that explain this link is limited. This study tested whether the social environment could get "under the skin" to alter genomic activity in children with asthma.

DESIGN AND PARTICIPANTS

Two group design of children with physician diagnosed asthma who came from low or high SES families.

OUTCOMES

Genome-wide transcriptional profiles from T lymphocytes of children with asthma.

RESULTS

Children with asthma from a low SES background showed overexpression of genes regulating inflammatory processes, including those involved in chemokine activity, stress responses and wound responses, compared with children with asthma from a high SES background. Bioinformatic analysis suggested that decreased activity of cyclic AMP response element binding protein and nuclear factor Y and increased nuclear factor kappaB transcriptional signalling mediated these effects. These pathways are known to regulate catecholamine and inflammatory signalling in immune cells.

CONCLUSIONS

This study provides the first evidence in a sample of paediatric patients diagnosed with asthma that the larger social environment can affect processes at the genomic level. Specifically, gene transcription control pathways that regulate inflammation and catecholamine signalling were found to vary by SES in children with asthma. Because these pathways are the primary targets of many asthma medications, these findings suggest that the larger social environment may alter molecular mechanisms that have implications for the efficacy of asthma therapeutics.

Identification of discrete chromosomal deletion by binary recursive partitioning of microarray differential expression data

DNA copy number abnormalities (CNA) are characteristic of tumours, and are also found in association with congenital anomalies and mental retardation. The ultimate impact of copy number abnormalities is manifested by the altered expression of the encoded genes. We previously developed a statistical method for the detection of simple chromosomal amplification using microarray expression data. In this study, we significantly advanced those analytical techniques to allow detection of localised chromosomal deletions based on differential gene expression data. Using three cell lines with known chromosomal deletions as model system, mRNA expression in those cells was compared with that observed in diploid cell lines of matched tissue origin. Results show that genes from deleted chromosomal regions are substantially over-represented (p<0.000001 by chi2) among genes identified as underexpressed in deletion cell lines relative to normal matching cells. Using a likelihood based statistical model, we were able to identify the breakpoint of the chromosomal deletion and match with the karyotype data in each cell line. In one such cell line, our analyses refined a previously identified 10p chromosomal deletion region. The deletion region was mapped to between 10p14 and 10p12, which was further confirmed by subtelomeric fluorescence in situ hybridisation. These data show that microarray differential expression data can be used to detect and map the boundaries of submicroscopic chromosomal deletions.

Impaired response to HAART in HIV-infected individuals with high autonomic nervous system activity

Neurotransmitters can accelerate HIV-1 replication in vitro, leading us to examine whether differences in autonomic nervous system (ANS) activity might promote residual HIV-1 replication in patients treated with highly active antiretroviral therapy. Patients who showed constitutively high levels of ANS activity before highly active antiretroviral therapy experienced poorer suppression of plasma viral load and poorer CD4(+) T cell recovery over 3-11 months of therapy. ANS activity was not related to demographic or behavioral characteristics that might influence pathogenesis. However, the ANS neurotransmitter norepinephrine enhanced replication of both CCR5- and CXCR4-tropic strains of HIV-1 in vitro via chemokine receptor up-regulation and enhanced viral gene expression, suggesting that neural activity may directly promote residual viral replication.

Simultaneous flow cytometric measurement of viability and lymphocyte subset proliferation

Combined analysis of DNA content and immunofluorescence on single cells by flow cytometry provides information on the proliferative response of cellular sub-populations in mixed cell preparations. However, the presence of considerable numbers of dead (nonviable) cells impairs accurate flow cytometric data analysis, mainly, because dead cells can bind antibodies non-specifically and show alterations in their DNA staining profiles. We developed a rapid method for identification of dead cells by fluorescence in cell preparations that are stained simultaneously for two-color immunofluorescence and DNA content. Cells are stained with 7-aminoactinomycin D (7-AAD) for dead cell discrimination and with fluorescein-isothiocyanate (FITC) and phycoerythrin (PE)-labeled monoclonal antibodies (mAb) for cell surface immunofluorescence. Diffusion of 7-AAD from stained, dead cells into unstained, live cells after cell permeabilization is blocked by the addition of its non-fluorescent analogue actinomycin D (AD). DNA is stained with red-excitable TO-PRO-3 iodide (TP3) which has an emission spectrum that can be effectively separated from the emissions of FITC, PE, and 7-AAD. TP3 staining is performed in the presence of ribonuclease A (RNAse) in phosphate-citrate buffer containing saponin (PCBS) at low pH. FITC fluorescence is sensitive to acid pH; therefore, PCBS is replaced after DNA staining with 1x PBS at pH 7.2 containing saponin to permit accurate detection of FITC immunofluorescence on the flow cytometer. We apply this method to the analysis of differential proliferation of lymphocyte subsets in cultures of human peripheral blood mononuclear cells (PBMC) with low viability.

Measurement of lymphocyte subset proliferation by three-color immunofluorescence and DNA flow cytometry

We developed a method for simultaneous flow cytometric analysis of three-color immunofluorescence and DNA content. We show here that staining with 7-amino-actinomycin D (7-AAD) at 10 microg/ml using a phosphate-citrate buffer at low pH containing saponin for cell membrane permeabilization yields good resolution DNA histograms with low coefficients of variation. Furthermore, light scatter properties of cells are preserved after permeabilization; this permits gating on cell populations that differ in scatter signals on the flow cytometer. Because of the low pH of the phosphate-citrate staining buffer, Alexa488, a pH-independent green-fluorescent fluorochrome is used instead of fluorescein-isothiocyanate (FITC) for cell surface staining in combination with phycoerythrin (PE) and with allophycocyanin (APC) which are both pH insensitive. Removal of 7-AAD after staining and replacing it with non-fluorescent actinomycin D (AD) retains DNA staining and allows detection of Alexa488, PE and APC cell surface immunofluorescence without interference from fluorescent 7-AAD in solution for clear identification of cell subpopulations even after prolonged stimulation in culture. Thus, using a four-color benchtop flow cytometer, measurement of Alexa488, PE and APC three-color immunofluorescence can be combined with 7-AAD DNA content analysis. Furthermore, we demonstrate that sample storage overnight without fixation for later analysis on the flow cytometer is possible without compromising results. Application of the method to the assessment of the differential proliferative responses of lymphocyte subsets of human peripheral blood mononuclear cells (PBMC) that were costimulated with CD3 and with CD28.2 is presented.

Detection of cell cycle subcompartments by flow cytometric estimation of DNA-RNA content in combination with dual-color immunofluorescence

BACKGROUND

Correlated flow cytometric measurements of phenotype and DNA-RNA content offer detailed information on cell cycle status of subpopulations in heterogeneous cell preparations in response to stimulation. We have developed a method for flow cytometric analysis of DNA-RNA content that has been optimized for simultaneous measurement of dual-color immunofluorescence.

METHODS

Nucleic acid staining was performed at low pH in the presence of saponin. DNA was stained with 7-aminoactinomycin D (7-AAD) and RNA with pyronin Y(G) (PY); both dyes were used at low concentrations, and 7-AAD was exchanged with nonfluorescent actinomycin D after DNA staining to minimize fluorochrome-fluorochrome interactions. For cell surface antigen staining, allophycocyanin was combined with pH-independent Alexa488 instead of fluorescein-isothiocyanate (FITC) because FITC is pH sensitive.

RESULTS

This method identified cell cycle subcompartments in CEM cells comparable to published results on cell lines using other dyes and staining methods. Measurement of DNA-RNA content in CD8 lymphocyte subsets of human peripheral blood mononuclear cells costimulated with CD3/CD28.2 showed that, after 48 h of stimulation, 80% of CD8(+) T cells were in the proliferative state, whereas 86% of CD8(+) non-T cells remained in G(0).

CONCLUSIONS

This technique permits the clear identification of cellular subpopulations by phenotype and assessment of their cell cycle status.

Reconstitution of human thymic implants is limited by human immunodeficiency virus breakthrough during antiretroviral therapy

Human immunodeficiency virus type 1 (HIV-1)-infected SCID-hu thymic implants depleted of CD4(+) cells can support renewed thymopoiesis derived from both endogenous and exogenous T-cell progenitors after combination antiretroviral therapy. However, successful production of new thymocytes occurs transiently. Possible explanations for the temporary nature of this thymic reconstitution include cessation of the thymic stromal support function, exhaustion of T-cell progenitors, and viral resurgence. Distinguishing between these processes is important for the development of therapeutic strategies aimed at reconstituting the CD4(+) T-cell compartment in HIV-1 infection. Using an HIV-1 strain engineered to express the murine HSA heat-stable antigen surface marker, we explored the relationship between HIV-1 expression and CD4(+) cell resurgence kinetics in HIV-1-depleted SCID-hu implants following drug therapy. Antiviral therapy significantly suppressed HIV-1 expression in double-positive (DP) CD4/CD8 thymocytes, and the eventual secondary decline of DP thymocytes following therapy was associated with renewed viral expression in this cell subset. Thymocytes derived from exogenous T-cell progenitors induced to differentiate in HIV-1-depleted, drug-treated thymic implants also became infected. These results indicate that in this model, suppression of viral replication occurs transiently and that, in spite of drug therapy, virus resurgence contributes to the transient nature of the renewed thymic function.

Socially inhibited individuals show heightened DTH response during intense social engagement

To determine whether altered cellular immune response might mediate the increased health risks associated with social inhibition, we examined delayed type hypersensitivity (DTH) responses in 36 adults under conditions of low and high intensity social engagement. Participants come from a study of psychological factors in functional bowel disease and fibromyalgia. Under high engagement conditions, socially inhibited individuals showed significantly increased induration in response to intradermal tetanus toxoid. Under low engagement conditions, these individuals showed less pronounced DTH responses that did not differ in magnitude from those of uninhibited individuals. This pattern of results was found using two different measures of social inhibition and was independent of social inhibition's definition as a continuously distributed trait vs a discrete category. These data are consistent with the general hypothesis that social inhibition represents a predisposition to physiologic hyperresponsiveness that requires an exogenous social trigger for expression.

Social relationships and the progression of human immunodeficiency virus infection: a review of evidence and possible underlying mechanisms

We review studies examining the quality and quantity of social relationships as potential risk factors for differential progression of human immunodeficiency virus (HIV) infection. Several well-conducted prospective studies suggest that the health effects associated with the presence of supportive social relationships vary according to disease stage and mode of transmission. For gay or bisexual males in the early stages of infection, the presence of supportive social relationships appears to be a risk factor for accelerated disease progression. For individuals in the later stages of infection and those who acquire HIV via intravenous drug use or transfusion, supportive social relationships appear to be associated with health protective effects similar to those observed in other disease settings. We consider a variety of potential explanations for accelerated disease progression in gay men with extensive networks of personal relationships.

cAMP up-regulates cell surface expression of lymphocyte CXCR4: implications for chemotaxis and HIV-1 infection

The chemokine receptor CXCR4 mediates lymphocyte chemotaxis in response to stromal cell-derived factor-1 (SDF-1) and functions as a coreceptor for T cell-tropic strains of HIV-1. We examined the role of the cAMP-protein kinase A (PKA) signaling pathway in regulating expression of CXCR4. In response to exogenous dibutyryl cAMP or cAMP-inducing ligands, cell surface expression of CXCR4 was increased by up to 10-fold on CD3/CD28-stimulated PBMC and by up to sixfold on unstimulated PBMC. cAMP did not alter receptor mRNA levels or affect the size of the total CXCR4 pool. However, cAMP did significantly reduce CXCR4 internalization rates and thereby increased the fraction of the total CXCR4 pool expressed on the cell surface. cAMP-induced increases in CXCR4 expression counteracted SDF-1-induced receptor internalization and enhanced both chemotactic response to SDF-1 and cellular vulnerability to HIV-1 infection. Thus, altered chemokine receptor expression may provide one mechanism by which cAMP-inducing ligands influence lymphocyte localization and HIV pathogenesis.

Norepinephrine accelerates HIV replication via protein kinase A-dependent effects on cytokine production

To explore the role of sympathetic nervous system activation in HIV pathogenesis, we examined the effect of the neuroeffector molecule norepinephrine (NE) on HIV-1 replication in quiescently infected PBMCs that were subsequently activated with Abs to CD3 and CD28. NE accelerated HIV-1 replication at concentrations ranging from 10(-8) to 10(-5) M. This effect could be mimicked by protein kinase A (PKA) activators (forskolin or dibutyryl-cAMP) and abrogated by beta-adrenoreceptor antagonists or the PKA inhibitor rp-cAMP, indicating transduction via the adrenoreceptor signaling pathway. NE reduced cellular activation and altered the production of several HIV-modulating cytokines: IL-10 and IFN-gamma were markedly suppressed; TNF-alpha, IL-1beta, IL-2, IL-4, and IL-6 were mildly suppressed; and levels of IL-12 were not significantly altered. The addition of either exogenous IFN-gamma or IL-10 abrogated the effect of NE on virus production. Thus PKA-dependent suppression of cytokine production appears to mediate the enhancement of HIV-1 replication by NE.

Social relationships and immune processes in HIV seropositive gay and bisexual men

This three-year longitudinal study assessed the association between social relationships and human immunodeficiency virus (HIV) progression in individuals at risk for morbidity and mortality due to acquired immune deficiency syndrome (AIDS). Two-hundred five HIV seropositive men without AIDS completed measures of social integration and loneliness at baseline. Blood samples used to assess CD4 T-lymphocyte levels were collected at baseline and at six-month intervals for a three-year follow-up period. Contrary to expectation, lower levels of baseline loneliness predicted more rapid declines in CD4 levels over the follow-up period. This association was independent of baseline CD4 values, negative affect, and health practices. A series of mediational analyses revealed that sexual behavior, medication use, bereavement, coping, and a number of other variables were not mechanisms through which loneliness affected the immune system. Loneliness was not associated with time to AIDS diagnosis or time to AIDS-related mortality. These findings are consistent with the emerging view that social relationships can have deleterious, as well as protective, influences on health outcomes.

Selective alteration of personality and social behavior by serotonergic intervention

OBJECTIVE

The authors sought to test the causal hypothesis that serotonergic function modulates aspects of the normal spectrum of individual differences in affective experience and social behavior in humans.

METHOD

A selective serotonin reuptake inhibitor (SSRI), paroxetine, 20 mg/day (N = 26), or placebo (N = 25) was administered to normal volunteers in a double-blind manner for 4 weeks, and personality variables and social behavior were assessed at baseline and at weeks 1 and 4 of treatment.

RESULTS

Relative to placebo, SSRI administration reduced focal indices of hostility through a more general decrease in negative affect, yet did not alter indices of positive affect. In addition, SSRI administration increased a behavioral index of social affiliation. Changes in both negative affect and affiliative behavior were significantly related to volunteers' plasma SSRI levels at the end of the experiment.

CONCLUSIONS

Central serotonergic function may modulate a dimension of normal personality characterized by reduced negative affective experience and increased affiliative behavior. SSRI administration has significant and detectable effects on these measures even in the absence of baseline clinical depression or other psychopathology.

Reduced viral load and lack of CD4 depletion in SCID-hu mice infected with Rev-independent clones of human immunodeficiency virus type 1

The posttranscriptional control element CTE of the simian type D retrovirus has been shown to support replication of Rev-Rev-responsive-element (RRE)-deficient molecular clones of human immunodeficiency virus type 1 (HIV-1). Upon infection of peripheral blood mononuclear cells in vitro, these CTE-containing Rev-independent viruses that are nef+ or nef-minus showed lower replicative capacity and infectivity than the wild-type HIV-1. We studied the effects of Rev-RRE replacement by the CTE on HIV-1 expression with SCID-hu mice. The nef+ and nef-minus Rev-independent viruses established infection with kinetics slower than that of the nef-minus NL4-3. Most importantly, no depletion of CD4-bearing thymocytes was observed after 6 weeks for mice infected with these Rev-independent viruses. This is in contrast to the infection with both wild-type and nef-minus viruses, which led to varying depletion of thymocytes. These data suggest an attenuated phenotype for growth and cytotoxicity of the Rev-independent HIV-1 clones in SCID-hu mice, independent of the presence of Nef. The mutant viruses, which have the essential Rev-RRE regulatory system eliminated, display a distinct phenotype not previously observed with HIV mutant viruses having deletions of accessory genes. Therefore, replacement of the Rev-RRE regulatory axis may generate viruses with altered biological properties in vivo.

Psychobiology of HIV infection

This review surveys evidence relevant to the proposition that psychobiologic factors may influence the progress of infection with human immunodeficiency virus Type 1 (HIV-1). Little research has directly examined the influence of psychobiologic factors on the pathogenetic mechanisms underlying HIV progression. However, basic research in neuroimmune interactions indicates that activation of the sympathetic nervous system and hypothalamic-pituitary-adrenal axis can influence several immunologic processes relevant to HIV pathogenesis and the body's ability to resist the progress of infection. A small number of observational natural history studies indicate that certain psychosocial characteristics may be associated with differential disease progression (e.g., subjective responses to highly threatening events, and inhibited psychosocial characteristics). We address some of the methodologic and conceptual issues critical to the interpretation of current results as evidence that psychobiologic processes influence HIV progression, and we conclude by highlighting promising areas for future inquiry.

Social identity and physical health: accelerated HIV progression in rejection-sensitive gay men

Research linking sensitivity to others and their evaluation of the self to alterations in physiologic function led the authors to examine whether HIV infection might progress more rapidly in gay men who are particularly sensitive to social rejection. Analyses of data from a 9-year prospective study of 72 initially healthy HIV-positive gay men indicated that rejection-sensitive individuals experienced a significant acceleration in times to a critically low CD4 T lymphocyte level, times to AIDS diagnosis, and times to HIV-related mortality (despite control for a variety of potential biobehavioral confounders). Accelerated HIV progression was not observed in rejection-sensitive gay men who concealed their homosexual identity, suggesting that concealment may protect such individuals from negative health effects. Data distinguishing rejection sensitivity from other health-relevant psychosocial characteristics are presented, and possible links to HIV pathophysiology are described.

Is the earlier age at onset of schizophrenia in males a confounded finding? Results from a cross-cultural investigation

BACKGROUND

The finding of an earlier age at onset of schizophrenia in males compared with females, replicated across a number of studies, appears to be so robust as to support hypotheses about gender differences in the aetiology of the disorder. However, the possibility that this observed gender effect might reflect other confounding variables has not been adequately explored.

METHOD

We analysed data on 778 men and 653 women, in three developing countries and in seven developed countries, who had been assessed in the WHO 10-country study of schizophrenia. We applied a generalised linear modelling strategy to estimate the unconfounded contributions of gender, family history, premorbid personality and marital status to age at onset.

RESULTS

The model that explained the highest percentage of the total variance indicated strong main effects (P < 0.001) for marital status and premorbid personality, a weak effect for family history, and an attenuated effect for gender. Two independent verification procedures suggested an independent onset-delaying effect for marital status (married), more marked in males.

CONCLUSIONS

The gender difference in the age at onset of schizophrenia is not a robust biological characteristic of the disorder. Failure to control for marital status and premorbid personality in male/ female comparisons of age at onset may explain a large part of the differences reported previously.

Social identity and physical health: accelerated HIV progression in rejection-sensitive gay men

Research linking sensitivity to others and their evaluation of the self to alterations in physiologic function led the authors to examine whether HIV infection might progress more rapidly in gay men who are particularly sensitive to social rejection. Analyses of data from a 9-year prospective study of 72 initially healthy HIV-positive gay men indicated that rejection-sensitive individuals experienced a significant acceleration in times to a critically low CD4 T lymphocyte level, times to AIDS diagnosis, and times to HIV-related mortality (despite control for a variety of potential biobehavioral confounders). Accelerated HIV progression was not observed in rejection-sensitive gay men who concealed their homosexual identity, suggesting that concealment may protect such individuals from negative health effects. Data distinguishing rejection sensitivity from other health-relevant psychosocial characteristics are presented, and possible links to HIV pathophysiology are described.

Elevated physical health risk among gay men who conceal their homosexual identity

This study examined the incidence of infectious and neoplastic diseases among 222 HIV-seronegative gay men who participated in the Natural History of AIDS Psychosocial Study. Those who concealed the expression of their homosexual identity experienced a significantly higher incidence of cancer (odds ratio = 3.18) and several infectious diseases (pneumonia, bronchitis, sinusitis, and tuberculosis; odds ratio = 2.91) over a 5-year follow-up period. These effects could not be attributed to differences in age, ethnicity, socioeconomic status, repressive coping style, health-relevant behavioral patterns (e.g., drug use, exercise), anxiety, depression, or reporting biases (e.g., negative affectivity, social desirability). Results are interpreted in the context of previous data linking concealed homosexual identity to other physical health outcomes (e.g., HIV progression and psychosomatic symptomatology) and theories linking psychological inhibition to physical illness.

Accelerated course of human immunodeficiency virus infection in gay men who conceal their homosexual identity

Research linking psychological inhibition to physical illness led us to examine whether human immunodeficiency virus (HIV) infection might progress more rapidly among gay men who conceal their homosexual identity than among those who do not. We also sought to determine whether any accelerated course of HIV infection among "closeted" gay men might be attributable to differences in health-relevant behavior (e.g., health practices, sexual behavior) or psychosocial characteristics (e.g., depression, anxiety, social support, repressive coping style). Data came from a longitudinal psychosocial study associated with the Los Angeles site of the Multicenter AIDS Cohort Study. Eighty gay men, HIV-seropositive but otherwise healthy at study entry (CD4 T lymphocytes = 30-60% of total lymphocytes), were examined at 6-month intervals for 9 years. Indicators of HIV progression included time to a critically low CD4 T lymphocyte level (15% of total peripheral blood lymphocytes), time to AIDS diagnosis, and time to AIDS mortality. On all measures, HIV infection advanced more rapidly in a dose-response relationship to the degree participants concealed their homosexual identity. Sample characteristics and statistical controls ruled out explanations based on demographic characteristics, health practices, sexual behavior, and antiretroviral therapy. Mediational analyses indicated that observed effects were not attributable to differences in depression, anxiety, social support, or repressive coping style. HIV infection appears to progress more rapidly in gay men who conceal their homosexual identity. These results are consistent with hypotheses about the health effects of psychological inhibition, but further research is required to definitively identify the psychosocial, behavioral, and physiological mechanisms underlying these findings.

Transference in social perception: the role of chronic accessibility in significant-other representations

Research has shown that the activation and application of a significant-other representation to a new person, or transference, occurs in everyday social perception (S. M. Andersen & A. Baum, 1994; S. M. Andersen & S. W. Cole, 1990). Using a combined idiographic and nomothetic experimental paradigm, two studies examined the role of chronic accessibility of significant-other representations in transference. After learning about 4 fictional people, 1 of whom resembled a significant other, participants' recognition memory was assessed. Both studies showed greater false-positive memory in the significant-other condition, relative to control, even in the absence of priming. Study 2 showed that although the effect was greater when the significant-other representation was concretely applicable to the target information, it occurred even when no such applicability was present. Results implicate the chronic accessibility of significant-other representations in transference.

Transference in social perception: the role of chronic accessibility in significant-other representations

Research has shown that the activation and application of a significant-other representation to a new person, or transference, occurs in everyday social perception (S. M. Andersen & A. Baum, 1994; S. M. Andersen & S. W. Cole, 1990). Using a combined idiographic and nomothetic experimental paradigm, two studies examined the role of chronic accessibility of significant-other representations in transference. After learning about 4 fictional people, 1 of whom resembled a significant other, participants' recognition memory was assessed. Both studies showed greater false-positive memory in the significant-other condition, relative to control, even in the absence of priming. Study 2 showed that although the effect was greater when the significant-other representation was concretely applicable to the target information, it occurred even when no such applicability was present. Results implicate the chronic accessibility of significant-other representations in transference.

"Do I know you?" The role of significant others in general social perception

This research used an idiographic method to examine the proposition that significant others are mentally represented as well-organized person categories that can influence social perception even more than representations of nonsignificant others, stereotypes, or traits. Together, Studies 1 and 2 showed that significant-other representations are richer, more distinctive, and more cognitively accessible than the other categories. Study 3 replicated the accessibility data and gauged inferential power by indirectly activating each category in a learning trial about a fictional person and then testing recognition memory. The results showed that participants made more category-consistent false-positive errors about targets who activated significant others vs. any other category. This constitutes the first experimental demonstration of transference and has implications both for social categorization and for basic personality processes.

"Do I know you?": The role of significant others in general social perception

This research used an idiographic method to examine the proposition that significant others are mentally represented as well-organized person categories that can influence social perception even more than representations of nonsignificant others, stereotypes, or traits. Together, Studies 1 and 2 showed that significant-other representations are richer, more distinctive, and more cognitively accessible than the other categories. Study 3 replicated the accessibility data and gauged inferential power by indirectly activating each category in a learning trial about a fictional person and then testing recognition memory. The results showed that participants made more category-consistent false-positive errors about targets who activated significant others vs. any other category. This constitutes the first experimental demonstration of transference and has implications both for social categorization and for basic personality processes.

Ultrasonography versus amniotic fluid spectral analysis: are they sensitive enough to predict neonatal complications associated with isoimmunization?

The modern management of pregnancy complicated by erythroblastosis fetalis is based on serial amniocenteses followed by either intrauterine transfusions or early delivery of affected infants, depending on the gestational age. A retrospective study was undertaken involving 92 isoimmunized pregnancies in which ultrasonography and amniotic fluid analyses were used to assess the relative predictive values for neonatal complications. Our data demonstrated that ultrasonography and optical density analyses were comparable in the evaluation of the isoimmunized pregnancy. The combined information from both these modalities did not increase the predictive value over that observed with either one alone. Both instruments were found to have high negative predictive values. However, neither method, used singly or in combination, was highly predictive of neonatal complications. In light of the low positive predictive values, caution should be exercised in using the results of amniotic fluid spectral analyses and/or ultrasound examinations for predicting perinatal complications.