C-Terminal Region of EBNA-2 Determines the Superior Transforming Ability of Type 1 Epstein-Barr Virus by Enhanced Gene Regulation of LMP-1 and CXCR7

Type 1 Epstein-Barr virus (EBV) strains immortalize B lymphocytes in vitro much more efficiently than type 2 EBV, a difference previously mapped to the EBNA-2 locus. Here we demonstrate that the greater transforming activity of type 1 EBV correlates with a stronger and more rapid induction of the viral oncogene LMP-1 and the cell gene CXCR7 (which are both required for proliferation of EBV-LCLs) during infection of primary B cells with recombinant viruses. Surprisingly, although the major sequence differences between type 1 and type 2 EBNA-2 lie in N-terminal parts of the protein, the superior ability of type 1 EBNA-2 to induce proliferation of EBV-infected lymphoblasts is mostly determined by the C-terminus of EBNA-2. Substitution of the C-terminus of type 1 EBNA-2 into the type 2 protein is sufficient to confer a type 1 growth phenotype and type 1 expression levels of LMP-1 and CXCR7 in an EREB2.5 cell growth assay. Within this region, the RG, CR7 and TAD domains are the minimum type 1 sequences required. Sequencing the C-terminus of EBNA-2 from additional EBV isolates showed high sequence identity within type 1 isolates or within type 2 isolates, indicating that the functional differences mapped are typical of EBV type sequences. The results indicate that the C-terminus of EBNA-2 accounts for the greater ability of type 1 EBV to promote B cell proliferation, through mechanisms that include higher induction of genes (LMP-1 and CXCR7) required for proliferation and survival of EBV-LCLs

Zen meditation, Length of Telomeres, and the Role of Experiential Avoidance and Compassion

Mindfulness refers to an awareness that emerges by intentionally focusing on the present experience in a nonjudgmental or evaluative manner. Evidence regarding its efficacy has been increasing exponentially, and recent research suggests that the practice of meditation is associated with longer leukocyte telomere length. However, the psychological mechanisms underlying this potential relationship are unknown. We examined the telomere lengths of a group of 20 Zen meditation experts and another 20 healthy matched comparison participants who had not previously meditated. We also measured multiple psychological variables related to meditation practice. Genomic DNA was extracted for telomere measurement using a Life Length proprietary program. High-throughput quantitative fluorescence in situ hybridization (HT-Q-FISH) was used to measure the telomere length distribution and the median telomere length (MTL). The meditators group had a longer MTL (p = 0.005) and a lower percentage of short telomeres in individual cells (p = 0.007) than those in the comparison group. To determine which of the psychological variables contributed more to telomere maintenance, two regression analyses were conducted. In the first model, which applied to the MTL, the following three factors were significant: age, absence of experiential avoidance, and Common Humanity subscale of the Self Compassion Scale. Similarly, in the model that examined the percentage of short telomeres, the same factors were significant: age, absence of experiential avoidance, and Common Humanity subscale of the Self Compassion Scale. Although limited by a small sample size, these results suggest that the absence of experiential avoidance of negative emotions and thoughts is integral to the connection between meditation and telomeres

Self-care for common colds: A European multicenter survey on the role of subjective discomfort and knowledge about the self-limited course - The COCO study

<div><p>Introduction</p><p>Common colds are the most frequently encountered disease worldwide and the most frequent reason for self-care. According to the cross-sectional European Common Colds study (COCO), patients use as many as 12 items on average for self-care. Little is known about the influence of discomfort and knowledge on self-care for common colds.</p><p>Main objective</p><p>To understand the influence of patients’ discomfort during a cold and their knowledge about the self-limited disease course on the use of self-care measures.</p><p>Materials and methods</p><p>This COCO analysis included 2,204 patients from 22 European primary care sites in 12 countries. Each site surveyed 120 consecutive adults with a 27-item questionnaire asking about patients’ self-care, subjective discomfort during a cold (discomfort: yes/no), and knowledge about the self-limited course (yes/no). Country-specific medians of the number of self-care items served as a cut-off to define high and low self-care use. Four groups were stratified based on discomfort (yes/no) and knowledge (yes/no).</p><p>Results</p><p>Participants’ mean age was 46.5 years, 61.7% were female; 36.3% lacked knowledge; 70.6% reported discomfort. The group <i>has discomfort/no knowledge</i> exhibited the highest mean item use (13.3), followed by <i>has discomfort/has knowledge</i> (11.9), <i>no discomfort/no knowledge</i> (11.1), and <i>no discomfort/has knowledge</i> (8.8). High use was associated with discomfort (OR 1.8; CI 1.5–2.2), female gender (OR 1.7; 1.4–2.0), chronic pain/arthritis (OR 1.6; 1.2–2.1), more years of education (OR 1.3; 1.1–1.6), age <48 years (OR 1.3; 1.0–1.5), and lack of knowledge (OR 1.2; 1.0–1.4).</p><p>Discussion</p><p>Counseling on common colds should address patients’ discomfort and soothing measures in addition to providing information on the natural disease course.</p></div

Induction of p16INK4a is the major barrier to proliferation when Epstein-Barr virus (EBV) transforms primary B cells into Lymphoblastoid cell lines

To explore the role of p16INK4a as an intrinsic barrier to B cell transformation by EBV, we transformed primary B cells from an individual homozygous for a deletion in the CDKN2A locus encoding p16INK4a and p14ARF. Using recombinant EBV-BAC viruses expressing conditional EBNA3C (3CHT), we developed a system that allows inactivation of EBNA3C in lymphoblastoid cell lines (LCLs) lacking active p16INK4a protein but expressing a functional 14ARF-fusion protein (p14/p16). The INK4a locus is epigenetically repressed by EBNA3C – in cooperation with EBNA3A – despite the absence of functional p16INK4a. Although inactivation of EBNA3C in LCLs from normal B cells leads to an increase in p16INK4a and growth arrest, EBNA3C inactivation in the p16INK4a-null LCLs has no impact on the rate of proliferation, establishing that the repression of INK4a is a major function of EBNA3C in EBV-driven LCL proliferation. This conditional LCL system allowed us to use microarray analysis to identify and confirm genes regulated specifically by EBNA3C, independently of proliferation changes modulated by the p16INK4a-Rb-E2F axis. Infections of normal primary B cells with recombinant EBV-BAC virus from which EBNA3C is deleted or with 3CHT EBV in the absence of activating ligand 4-hydroxytamoxifen, revealed that EBNA3C is necessary to overcome an EBV-driven increase in p16INK4a expression and concomitant block to proliferation 2–4 weeks post-infection. If cells are p16INK4a-null, functional EBNA3C is dispensable for the outgrowth of LCLs