Julia R. Gage

Beta Blocker and Angiotensin-Converting Enzyme Inhibitor Therapy Is Associated with Decreased Th1/Th2 Cytokine Ratios and Inflammatory Cytokine Production in Patients with Chronic Heart Failure

Objective: To examine the potential impact of β-blockers and angiotensin-converting enzyme (ACE) inhibitors, medications which modulate β-adrenergic signaling, on immune function in patients with chronic heart failure (HF). Methods: 118 patients attending an HF center were tested for circulating levels of norepinephrine (NE), T cells and the inflammation-associated cytokine interleukin 6 (IL-6). Levels of the cytokines interferon-γ (IFNγ), IL-10, and tumor necrosis factor-α (TNFα) produced by cultured peripheral blood mononuclear cells (PBMC) were measured in culture supernatants following T cell stimulation in vitro. Results: NE levels were significantly lower in patients receiving ACE inhibitors (p = 0.0263), with a trend toward lower NE in patients receiving β-blockers. All patients exhibited relatively normal levels of T cells, and there was a trend toward higher levels of total (CD3+) and helper (CD4+) T cells (p = 0.0578 and 0.0932, respectively) in patients receiving either type of medication. The ratios of Th1 (IFNγ) to Th2 (IL-10) cytokines were lower in patients receiving a combination of β-blocker and ACE inhibitor therapy (p = 0.0373). NYHA class was a significant predictor of serum IL-6 (p < 0.0001). There was a trend toward lower levels of serum IL-6 in patients receiving both types of medications (p = 0.0606). TNFα production by CD3/CD28-stimulated PBMC was significantly lower in patients receiving ACE inhibitor medications (p = 0.0223). Conclusions: These results suggest that high sympathetic tone associated with chronic HF affects Th1/Th2 and inflammatory cytokine production, and that these effects can be modulated by medications. In addition to improvement in clinical parameters relating to cardiovascular function, β-blocker and ACE inhibitor medications also appear to have a beneficial effect on the immune system in HF.

Effects of human papillomavirus-associated cells on human immunodeficiency virus gene expression.

Objective To examine the effects of soluble factors secreted by human papillomavirus (HPV)-associated cells on human immunodeficiency virus (HIV) expression. Methods Supernatants collected from cultured cervical biopsies and cervical cancer cell lines, and HPV-immortalized and normal keratinocytes were tested for the ability to induce HIV p24 production in two cell lines that contained latent HIV (the U1 monocytic line and the ACH-2 T cell line). Levels of HIV p24 were measured by enzyme-linked immunosorbent assay (ELISA). Culture supernatants were also assayed for the inflammatory cytokines interleukin 6, tumor necrosis factor, and interleukin 1β by ELISA. Results Supernatants from all epithelial cells tested upregulated HIV p24 expression in the U1 line but not in the ACH-2 cells. Only differentiated normal keratinocytes induced p24 production by ACH-2 cells. Neutralization of the cytokines, particularly interleukin 6, partially reduced the level of HIV-inducing activity in the culture supernatants. Additionally, cervical biopsies from HIV-infected women cultured in vitro also were able to induce HIV in U1 cells but not ACH-2 cells. Conclusions Our results suggest that HPV infection of the cervix might influence HIV pathogenesis by inducing the production of immune and inflammatory factors that enhance HIV expression.

Human papillomavirus type 16 immortalized cervical keratinocytes contain transcripts encoding E6, E7, and E2 initiated at the P97 promoter and express high levels of E7

Human cervical keratinocytes represent the specific host for the genital human papillomaviruses (HPV). Transfection of these cells with the DNA of a number of the oncogenic HPVs including type 16 was recently shown to result in their immortalization but not in malignant transformation. In this report we show that viral transcripts for E6 and E7 in these cells were as abundant as in cancer derived cell lines. However, in contrast to cancer derived cell lines, immortalized cervical keratinocytes contained RNA with the potential to encode a full-length E2 protein. In addition, the levels of the E7 oncoprotein were at least as high as in cancer derived cell lines, suggesting that E2 interruption, observed in cancer derived cell lines, is not causally related to the high level of E7 expression and, therefore, deregulation of the P97 promoter may not be a prerequisite for HPV-16 associated cancer development. Furthermore, we show that E6, E7, and E2 encoding transcripts all originate from the viral promoter, P97. Unlike in cancer derived cell lines, all transcripts terminated at the early poly(A) site.

Cytokine-mediated modulation of cisplatin sensitivity in ovarian cancer cells

Abstract Background: Epithelial ovarian cancer cells are known to produce interleukin-6 (IL-6) and are known to express IL-6 receptors. Serum and peritoneal fluid concentrations of IL-6 are elevated in patients with epithelial ovarian cancers. Metallothioneins are a group of proteins with high affinity for heavy metal ions, including platinum; they are inducible by IL-6 and may confer resistance of ovarian cancer cells to cisplatin chemotherapy. Objective: To determine whether IL-6 induces cisplatin resistance in ovarian cancer cells and to assess whether it does so by increasing intracellular metallothionein. Methods: Two ovarian cancer cell lines (SKOV3, OC194) were incubated with either recombinant IL-6, anti-IL-6 antibody, anti-IL-6 receptor antibody, or IL-10 for 24 hours. Cisplatin was then added, and an MTT (3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) cytotoxicity assay was performed after 48 hours. Western blot probing for metallothionein was performed after a 24-hour incubation of SKOV3 cells with IL-6. Results: Pretreatment of ovarian cancer cells with IL-6 before adding cisplatin resulted in a significant reduction in cytotoxicity. Reversal of this IL-6 effect with anti-IL-6 antibody, anti-IL-6 receptor antibody, and IL-10 was demonstrated. Western blot analysis of IL-6–treated cells revealed a positive correlation between IL-6 exposure and cellular metallothionein content. Conclusion: These results demonstrate that expression of IL-6 by ovarian cancer cells confers resistance to cisplatin cytotoxicity by upregulation of metallothione. In addition, inhibition of IL-6 effect reverses this cisplatin resistance. Clinically, suppression of IL-6 effect may be exploited to potentiate cisplatin chemotherapy, leading to better survival rates in ovarian cancer patients.