Association of CD4+ T cell subpopulations and psychological stress measures in women living with HIV.

Psychological stress is a known immunomodulator. In individuals with HIV, depression, the most common manifestation of increased psychological stress, can affect immune function with lower CD4+ T cell counts correlating with higher levels of depression. It is unknown how other forms of psychological stress can impact immune markers in people living with HIV. We conducted a cross-sectional study to determine how CD4+ T cell subpopulations correlated with different forms of psychological stress. We recruited 50 HIV-positive women as part of the Women's Interagency HIV Study. We assessed perceived stress, worry, acute anxiety, trait anxiety, and depression through self-report questionnaires and CD4+ T cell subpopulations using flow cytometry. Our sample was 96% African-American with a mean ± SD age and body mass index of 42 ± 8.8 years and 36.6 ± 11.5 kg/m2, respectively. The mean ± SD scores on the psychological measures were as follows: Perceived Stress Scale (PSS), 16.5 ± 6.4; Penn State Worry Questionnaire (PSWQ), 47.7 ± 13.8; State-Trait Anxiety Inventory - State (STAIS), 39.1 ± 12.3; State-Trait Anxiety Inventory - Trait (STAIT), 40.2 ± 11.4; Center for Epidemiological Studies Depression Scale (CES-D), 15.6 ± 11.4. The mean + SD values for the immune parameters were as follows: regulatory T cells (Treg), 1.25% ± 0.7; T helper 1 (Th1), 14.9% ± 6.1; T helper 2 (Th2), 3.8% ± 2; Th1/Th2 ratio, 4.6 ± 3; and CD4+ T cell count (cells/mm3), 493 ± 251. Treg levels positively correlated with PSS, STAIS, and STAIT. CD4+ T cell count negatively correlated with PSS, PSWQ, STAIS, STAIT, and CES-D. These data suggest that immune function may be impacted by various forms of psychological stress in HIV-positive women. Interventions that target stress reduction may be useful in improving immune parameters and quality of life.

Physical activity levels and perceived benefits and barriers to physical activity in HIV-infected women living in the deep south of the United States.

Engaging in regular physical activity (PA) is important in maintaining health and increasing the overall quality of life of people living with HIV (PLWH). The deep south of the USA is known for its high rate of sedentary behavior although data on the activity levels and perceptions of the benefits and barriers to exercise in women living with HIV in the deep south are lacking. Understanding the perceived benefits and barriers to exercise can guide the development of PA interventions. We conducted a cross-sectional study to determine the PA levels and perceived benefits and barriers to exercise associated with both age and depression level in a group of HIV+ women living in the deep south. We recruited a total of 50 participants from a cohort site for the Women's Interagency HIV Study. Depression was assessed using the Center for Epidemiological Studies Depression Scale (CES-D) and benefits/barriers to exercise were measured using the Exercise Benefits and Barriers Scale (EBBS). We measured PA both subjectively and objectively using the International Physical Activity Questionnaire (IPAQ) and a Fitbit PA monitor, respectively. Our sample was predominantly African-American (96%) and the mean ±SD age, body mass index, and CES-D score were 42 ± 8.8 years, 36.6 ± 11.5 kg/m(2), and 15.6 ± 11.4, respectively. Both subjective and objective measures of PA indicated that our participants were sedentary. The greatest perceived benefit to exercise was physical performance and the greatest barrier to exercise was physical exertion. Higher overall perceived benefits were reported by women ≥43 years and women reporting higher levels of depression. There was no difference in overall barriers associated with age and depression level, but women with depression felt more fatigued by exercise. The results of this study can be helpful when designing and implementing PA interventions in women living with HIV in the deep south.

A modified and cost-effective method for hair cortisol analysis.

Hair cortisol may hold potential as a biomarker for assessment of chronic psychological stress. We report a modified and cost-effective method to prepare hair samples for cortisol assay. Hair samples were ground using an inexpensive ball grinder - ULTRA-TURRAX tube drive. Cortisol was extracted from the powder under various defined conditions. The data showed that the optimal conditions for this method include cortisol extraction at room temperature and evaporation using a stream of room air. These findings should allow more widespread research using economical technology to validate the utility of hair cortisol as a biomarker for assessing chronic stress status.

Hair Cortisol Concentrations Are Associated with Hair Growth Rate.

There is a growing interest in hair cortisol concentrations as a valuable biomarker for the assessment of metabolic diseases and chronic psychological stress. Fifty-three volunteers were recruited, and hair segments proximal to the scalp were collected from each individual. A cost-effective ball mill was used for the preparation of hair samples, and ELISA was performed to analyze cortisol concentrations. Results indicate that the frequency of hair washing affects the hair cortisol concentration. The group that washed their hair every day had significantly lower cortisol concentrations than the group that washed it less often. However, no significant differences were detected between cosmetic-treated and nontreated hair samples. The study also shows that hair cortisol concentrations in the first 3 cm of hair segments proximal to the scalp corresponded to average hair growth rate based on 1 cm/month. Thus, hair cortisol concentrations of segments 3 cm proximal to the scalp may represent cumulative stress exposure over the previous 3 months. These findings will allow more widespread research to validate the utility of hair cortisol as a potential biomarker to assess chronic stress.

Gene polymorphisms of stress hormone and cytokine receptors associate with immunomodulatory profile and psychological measurement.

OBJECTIVE: We sought to identify whether stable single nucleotide polymorphisms (SNPs) of various endocrine and immune molecules could be used as biomarkers associated with specific immune alterations and chronic stress measures in normal humans. METHODS: A total of 207 volunteer participants answered stress questionnaire and gave peripheral blood cells for identification of SNPs in genes coding for glucocorticoid receptor (GR), beta 2 adrenergic receptor (B2AR), interferon-gamma receptors (IFNGR1, IFNGR2), and interleukin-4 receptor (IL4R). Immunoregulatory profiles were measured by flow cytometry and genotyping assays were performed by allelic discrimination real-time PCR. RESULTS: Several significant differences were revealed in associations between stress marker and immune indicators based on SNP categories. For instance, Th1 levels of the minor alleles of GR TthIIII (AA) and IFNGR2 Q64R (Arg/Arg) groups were positively associated with chronic stress (PSS) (p = 0.024 and 0.005, respectively) compared with wild type (WT) and negatively associated with PSS in the heterozygous genotypes of GR BclI and IL4R Ile50Val (p = 0.040 and p = 0.052, respectively). Treg levels of the minor alleles of BclI (GG) and IFNGR1 T-56C (CC) groups were positively associated with PSS (p = 0.045 and p = 0.010, respectively) and negatively associated in the minor allele (Val/Val) of IL4R Ile50Va and the heterozygous genotype of IL4R Q576R (p = 0.041 and p = 0.017, respectively) compared to WT. CONCLUSION: The data support the notion that gene polymorphisms from various components of the psychoneuroendocrine-immune network may be useful as biomarkers to categorize individual stress-associated immune responses.

Effects of strenuous exercise on Th1/Th2 gene expression from human peripheral blood mononuclear cells of marathon participants.

Physical stressors, such as strenuous exercise, can have numerous effects on the human body including the immune system. The aim of this study was to evaluate the gene expression profile of Th1/Th2 cytokines and related transcription factor genes in order to investigate possible immune imbalances before and after a marathon. Blood samples were collected from 16 normal volunteers 24-48 h before and one week after completing a marathon race. Gene expression of Th1 and Th2 related cytokines from human peripheral blood mononuclear cells (PBMC) was analyzed using Human Th1-Th2-Th3 RT(2) Profiler PCR Array and qRT-PCR that measured the transcript levels of 84 genes related to T cell activation. We found that PBMC express a characteristic Th2-like gene profile one week post-marathon compared to pre-marathon. The majority of genes up-regulated one week post-marathon such as IL-4, GATA3, and CCR4 were Th2 associated. For Th1-related genes, CXCR3 and IRF1 were up-regulated one week post-marathon. There was a trend of down-regulation of two Th1 related genes, T-bet and STAT1. Th3-related gene expression patterns did not change in the study. The ratios of both IFN-γ/IL-4 and T-bet/GATA3 gene expressions were significantly lower one week after marathon. These findings suggest that a Th1/Th2 immune imbalance persisted at least 1 week after completion of a marathon which offers a mechanistic rationale for the increased risk of upper respiratory tract infections often reported after strenuous exercise.

Associations between cytokine receptor polymorphisms and variability in laboratory immune parameters in normal humans.

In every study involving human immune parameters, large inter-subject variability occurs which can make interpretation of results difficult. The aim of this study was to evaluate whether genetic variants in cytokine receptors could associate with variability in laboratory immune measures. A total of 207 normal volunteers were recruited in this study. Immunoregulatory profiles were measured by flow cytometry and genotyping assays were performed by allelic discrimination real-time PCR. Immunoregulatory profiles were categorized according to various single nucleotide polymorphisms (SNPs) of cytokine receptors including T-56C and G-611A of IFN-γ receptor 1 (IFNGR1); Q64R of IFNGR2; and Ile50Val, Q576R and S503P of IL4R. Results reveal that Th1 levels were significantly higher in the heterozygous of the IFNGR1 T-56C polymorphism (minor allele) compared to wild-type (WT, major allele) (p = 0.006). For the Q576R of IL4R, Th1/Th2 ratio was significantly lower for the homozygous SNP (Arg/Arg) compared to the WT (Gln/Gln) (p = 0.035). In addition, the significant interaction effects of demographic characteristics on SNP-immune parameter associations were reported as well. We conclude that cytokine receptor polymorphisms might associate with variability in laboratory immune measures. Approach of SNP analysis of cytokine receptors can be useful in categorizing baseline immune responses to more accurately evaluate clinical immune data.

The impact of self-reported psychological stress levels on changes to peripheral blood immune biomarkers in recreational marathon runners during training and recovery.

OBJECTIVE: Marathon training is both physically and psychologically stressful, both of which can lead to altered immunity. The purpose of this study was to determine if the overall immunoregulatory changes associated with the physical stress of marathon training are affected by psychological stress. METHODS: Nineteen recreational marathoners completed the Perceived Stress Scale (PSS), State-Trait Anxiety Inventory (STAI) and Penn State Worry Questionnaire (PSWQ), and had levels of T cell subpopulations and cytokine (IFNγ, IL4 and IL10) production determined 4 weeks before (baseline), 24-48 h before (prerace) and 1 week after (recovery) participation in a marathon. RESULTS: PSS scores decreased at the prerace visit compared to baseline and remained low at recovery. Compared to baseline, there were significant changes to numerous immune measures at the prerace visit, including decreases in Th1/Th2 ratio, Tc1/Tc2 ratio, Tr1 and Th3 cell populations as well as decreases in IFNγ/IL4 cytokine ratio and IL10 production. Most immune parameters had returned to near baseline values at the recovery visit. Higher levels of perceived stress, anxiety and worry exacerbated many of the alterations in immunity that were observed at the prerace visit. Higher levels of perceived stress and worry had significant effects on changes to Treg, IL4 production and the IFNγ/IL4 cytokine ratio. Stress had an additional impact on changes in IL10 production. High anxiety levels resulted in significant changes to Treg, Tr1 and Th3. CONCLUSION: These data suggest that recreational marathon runners with higher levels of psychological stress may be more at risk for the immune alterations that are common during periods of prolonged physical training.

Variability in laboratory immune parameters is associated with stress hormone receptor polymorphisms.

OBJECTIVES: Interpretation of laboratory immune data in healthy human subjects is often challenging due to wide inter-subject variability. Since endocrine and immune mediators have been mutually interlinked, a potential explanation for the significant variability seen in immune data even when controlled for technical variability and demographics is differences in the binding affinity of ligand with hormone receptors on the surface of immune cells, which can be associated with single nucleotide polymorphisms (SNP). METHODS: We categorized immunoregulatory cellular profiles from PBMC of 207 healthy volunteers according to glucocorticoid receptor (GR: Bcl1, TthIIII, and A3669G) and ß2-adrenergic receptor (ß2AR: Gly16Arg and Gln27Glu) polymorphisms. Subjects were genotyped for each SNP, and Th1, Th2, Th1/Th2 ratio, regulatory T cell (T(reg)), Tr1, and Th3 cell numbers were assessed. Immune parameters in the SNP groups were compared to the wild type (WT). RESULTS: Significant differences were observed in Th2 and the Th1/Th2 ratio for the ß2AR SNP Gly16Arg. Th1, the Th1/Th2 ratio, and Tr1 differed significantly by SNP of Gln27Glu. In addition, the effect of age on Th2 and the effect of the body mass index on the Th1/Th2 ratio significantly differed across subtypes of the Gly16Arg SNP. Significant differences based on allergic status and gender were also seen for T(reg), Th1, and Th2 across Gly16Arg, Gln27Glu, and TthIIII SNP. CONCLUSIONS: These data suggest that SNP from various components of the stress-immune network may be useful for subgrouping of immune responses to more accurately categorize psychoneuroimmunological components of stress risk in individual subjects. This approach may have significant research and clinical potential.

Effects of acute stress-induced immunomodulation on TH1/TH2 cytokine and catecholamine receptor expression in human peripheral blood cells.

AIMS: There is evidence that psychological stress can modulate immune functions. It has been hypothesized that acute stressors can affect both immune balance (including Th1 and Th2 cytokines) and expression of stress hormone receptors. This study investigated the impact of an acute stressor on gene expressions of glucocorticoid receptor (GR), and ß2-adrenergic receptor (ß2AR) in leukocytes. The effect on T regulatory cells (Treg), regulatory cytokines IL-10 and TGF-ß, Th1 and Th2 cytokines and their receptors IFN-γR and IL-4R was also studied. METHOD: Fourteen normal volunteers completed an acute laboratory stressor, and blood samples were collected before, immediately after, and 1, 2, 6 and 24 h after completion of the tasks. Cytokine production and Treg were determined by flow cytometry. Gene expressions of receptors were analyzed by real-time PCR. RESULTS: IFN-γ was increased immediately and 1 h after stressor (p<0.05, respectively) and upregulation of IFN-γR mRNA was noted at 2, 6 and 24 h (p<0.01, respectively). IL-10 was decreased at 2 h (p<0.01). There were no significant changes in post-task IL-4R, Treg, or TGF-ß. ß2AR mRNA was increased at 2, 6 and 24 h (p<0.01, respectively). On the other hand, no significant alterations were observed in GR expression. CONCLUSION: An acute stressor increased Th1 cytokine production and its receptor expression. ß2AR but not GR was significantly increased after an acute stressor, which supports the hypothesis that catecholamine-mediated signal pathways in communication with the central nervous and immune systems play a fundamental role in acute stress-mediated immune alterations.

Deletion of the A35 gene from Modified Vaccinia Virus Ankara increases immunogenicity and isotype switching.

We show here that the immunogenicity of the Modified Vaccinia Ankara MVA vaccine strain can be improved by deletion of the A35 gene, without diminishing the ability of the virus to replicate. Deletion of the A35 gene resulted in increased virus-specific immunoglobulin production, class switching to IgG isotypes, and virus-specific IFNγ-secreting splenocytes. The MVA35 deletion virus provided excellent protective efficacy against virulent virus challenge. These results suggest that A35 deletion mutant strains will have superior vaccine performance for poxvirus vaccines as well as platform vaccines for other infectious diseases and cancer.

Stress and allergic diseases.

Allergy describes a constellation of clinical diseases that affect up to 30% of the world's population. It is characterized by production of allergen-specific IgE, which binds to mast cells and initiates a cascade of molecular and cellular events that affect the respiratory tract (rhinitis and asthma), skin (dermatitis, urticaria), and multiple systems (anaphylaxis) in response to a variety of allergens including pollens, mold spores, animal danders, insect stings, foods, and drugs. The underlying pathophysiology involves immunoregulatory dysfunctions similar to those noted in highly stressed populations. The relationships in terms of potential for intervention are discussed.

Vaccinia virus A35R inhibits MHC class II antigen presentation.

The Vaccinia virus gene A35R (Copenhagen designation) is highly conserved in mammalian-tropic poxviruses and is an important virulence factor, but its function was unknown. We show herein that A35 does not affect viral infectivity, apoptosis induction, or replication; however, we found that A35 significantly inhibited MHC class II-restricted antigen presentation, immune priming of T lymphocytes, and subsequent chemokine and cytokine synthesis. A35 localized to endosomes and reduced the amount of a model antigenic peptide displayed in the cleft of class II MHC. In addition, A35 decreased VV specific T cell responses in vivo. Thus, this is the first report identifying a function for the A35 protein in virulence as well as the first report identifying a VV gene that inhibits peptide antigen presentation.

The poxvirus A35 protein is an immunoregulator.

It was shown previously that the highly conserved vaccinia virus A35 gene is an important virulence factor in respiratory infection of mice. We show here that A35 is also required for full virulence by the intraperitoneal route of infection. A virus mutant in which the A35 gene has been removed replicated normally and elicited improved antibody, gamma interferon-secreting cell, and cytotoxic T-lymphocyte responses compared to wild-type virus, suggesting that A35 increases poxvirus virulence by immunomodulation. The enhanced immune response correlated with an improved control of viral titers in target organs after the development of the specific immune response. Finally, the A35 deletion mutant virus also provided protection from lethal challenge (1,000 50% lethal doses) equal to that of the wild-type virus. Together, these data suggest that A35 deletion viruses will make safer and more efficacious vaccines for poxviruses. In addition, the A35 deletion viruses will serve as improved platform vectors for other infectious diseases and cancer and will be superior vaccine choices for postexposure poxvirus vaccination, as they also provide improved kinetics of the immune response.

SARS vaccines: where are we?

In this review, the current state of vaccine development against human severe acute respiratory syndrome (SARS) coronavirus, focusing on recently published data is assessed. We discuss which strategies have been assessed immunologically and which have been evaluated in SARS coronavirus challenge models. We discuss inactivated vaccines, virally and bacterially vectored vaccines, recombinant protein and DNA vaccines, as well as the use of attenuated vaccines. Data regarding the correlates of protection, animal models and the available evidence regarding potential vaccine enhancement of SARS disease are discussed. While there is much evidence that various vaccine strategies against SARS are safe and immunogenic, vaccinated animals still display significant disease upon challenge. Current data suggest that intranasal vaccination may be crucial and that new or combination strategies may be required for good protective efficacy against SARS in humans.

Vaccinia virus decreases major histocompatibility complex (MHC) class II antigen presentation, T-cell priming, and peptide association with MHC class II.

Vaccinia virus (VACV) is the current live virus vaccine used to protect humans against smallpox and monkeypox, but its use is contraindicated in several populations because of its virulence. It is therefore important to elucidate the immune evasion mechanisms of VACV. We found that VACV infection of antigen-presenting cells (APCs) significantly decreased major histocompatibility complex (MHC) II antigen presentation and decreased synthesis of 13 chemokines and cytokines, suggesting a potent viral mechanism for immune evasion. In these model systems, responding T cells were not directly affected by virus, indicating that VACV directly affects the APC. VACV significantly decreased nitric oxide production by peritoneal exudate cells and the RAW macrophage cell line in response to lipopolysaccharide (LPS) and interferon (IFN)-gamma, decreased class II MHC expression on APCs, and induced apoptosis in macrophages and dendritic cells. However, VACV decreased antigen presentation by 1153 B cells without apparent apoptosis induction, indicating that VACV differentially affects B lymphocytes and other APCs. We show that the key mechanism of VACV inhibition of antigen presentation may be its reduction of antigenic peptide loaded into the cleft of MHC class II molecules. These data indicate that VACV evades the host immune response by impairing critical functions of the APC.