Alberto Biglino

Cytokine network and acute primary HIV-1 infection.

Objective:To investigate the relationship between cytokine serum levels, peripheral blood lymphocyte subsets and clinical picture in acute primary HIV-1 infection. Patients and methods:Absolute number/μl total lymphocytes, CD4+, CD8+ and natural killer (NK) cells, as well as serum levels of soluble CD8 receptor, interleukin (IL)-1β, IL-2, lL-4, IL-6, tumour necrosis factor (TNF)-α, interferon (IFN)-γ, β2-microglobulin and 5′-neopterin were determined in 15 patients with acute primary HIV-1 infection, 16 asymptomatic HIV-1-seropositive individuals and 18 HIV-1-seronegative individuals at risk for HIV-1 infection. Results:Acute primary HIV-1 infection was characterized by significant CD4+ lymphocytopenia with low IL-2 serum concentrations, and by high absolute number of circulating CD8+ and NK cells, with elevated serum levels of soluble CD8 receptor, IL-1β, IFN-γ and 5′-neopterin. Follow-up of acute seroconverters showed a significant decrease in NK cell counts and 1L-1β levels, with an increase of IL-6. Conclusions:In acute primary HIV-1 infection, significant alteration of cytokine release, possibly induced by viral antigens, could be responsible for both clinical picture and activation of cytotoxic cells through abnormal mechanisms.

Asymptomatic Leishmania infantum Infection in an Area of Northwestern Italy (Piedmont Region) Where Such Infections Are Traditionally Nonendemic

ABSTRACT The prevalence of Leishmania infantum-specific antibodies and asymptomatic infection was assessed in a randomized sample of 526 healthy adults from a continental area of Northwestern Italy where L. infantum is not endemic and where autochthonous cases of visceral leishmaniasis (VL) were recently reported. L. infantum-specific antibodies were detected by Western blotting (WB) in 39 subjects (7.41%), while L. infantum kinetoplast DNA was amplified from buffy coat in 21 out of 39 WB-positive subjects, confirming asymptomatic infection in 53.8% of seropositives. Risk factors significantly associated with WB positivity were uninterrupted residence since childhood in a local rural environment (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.7 to 7.3), daily contact with animals though not exclusively with dogs (OR, 3.7; 95% CI, 1.3 to 10.7), older age (OR, 2.31; 95% CI, 1.2 to 4.5), and agricultural/other outdoor activities (OR, 3.8; 95% CI, 0.99 to 3.7.) Logistic regression analysis showed that uninterrupted residence in a local rural environment and an age of >65 years were the only independent predictors of seropositivity assessed by WB. Follow-up at 24 months did not show evidence of VL in either seropositive or PCR-positive subjects. The detection of a high seroprevalence rate, confirmed as asymptomatic infection by PCR in more than half of the cases, among healthy residents in a continental area of northwestern Italy makes local L. infantum transmission very likely. In a region where VL is considered nonendemic, these findings warrant further epidemiological investigations as well as interventions with respect to both the canine reservoir and vectors, given the possible risks for immunosuppressed patients.

Interferon and amantadine in combination as initial treatment for chronic hepatitis C patients

BACKGROUND/AIMS To evaluate the efficacy and tolerance of amantadine in combination with interferon in the treatment of chronic hepatitis C. METHODS Multi-centre trial including 180 chronic hepatitis C patients without cirrhosis, randomly enrolled to receive interferon 6 MU every other day for 6 months followed by 3 MU for further 6 months (group A, 90 patients), or the same schedule plus amantadine 200 mg/day (group B, 90 patients). Primary end-point was a sustained virological and biochemical response, secondary end-points were on-treatment (third month) and end-of-treatment response rates. RESULTS The two groups had similar demographic, biochemical and virological characteristics. A sustained response after 6 months follow-up was observed in 17% of group A and 24% of group B patients (P not significant), an end-of-treatment response was observed in 37% in group A and 47% in group B (P not significant), an on-treatment response was observed in 46% in group A and 61% in group B patients (P < 0.05). No major side effects due to amantadine administration were observed. CONCLUSIONS Adding amantadine to interferon did not improve the sustained treatment efficacy. However, the rate of early response at the third month of therapy was significantly higher in the combination therapy group.

Evidence for a positive correlation between serum cortisol levels and IL-1β production by peripheral mononuclear cells in anorexia nervosa

A hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis has been reported in anorexia nervosa (AN), together with some immunological abnormalities, involving citokine — and particularly Tumor Necrosis-Factor-α (TNF-α) — production by polymorphonuclear cells. The ability of pro-inflammatory cytokines to activate the HPA axis is well known; however, there are no data demonstrating an interdependence between immunological and endocrine response in AN. To investigate the presence of a correlation between immune response and pituitary-adrenal function, plasma ACTH and serum cortisol concentrations were measured in 13 AN patients and in the same number of controls. TNF-α and interleukin (IL)-1β production by ex-vivo unstimulated and LPS-stimulated peripheral mononuclear cells was also assessed. Circulating cortisol concentrations were higher (p<0.01) in AN (156.7±45.1 μg/l, mean±SD) than in controls (105.9±25.7 μg/l). Unstimulated IL-1β release in supernatants of mononuclear cell cultures was slightly but not significantly higher in AN than in controls, while TNF-α release was similar in the two groups. A positive correlation was found between IL-1β concentrations in unstimulated culture supranatants and serum cortisol levels in AN (r=0.782, p=0.002), while in normal subjects there was a trend toward a negative correlation; a slight positive correlation, while not significant, between IL-1β and plasma ACTH, as well as between TNF-α and serum cortisol was also found in AN. These data suggest that the normal relationship between pro-inflammatory cytokines release, particularly IL-1β and cortisol secretion is deranged in AN.

Clinical Usefulness of ELISPOT Assay on Pericardial Fluid in a Case of Suspected Tuberculous Pericarditis

Rapid and accurate diagnosis of tuberculous pericarditis is often difficult, considering the low specificity of both clinical picture and laboratory tests on pericardial fluid, as well as the low sensitivity of microbiological tests. This report documents the feasibility and clinical usefulness of an Interferon (IFN) – gamma ELISpot – TB assay on pericardial fluid cells in a case of suspected tuberculous pericarditis presenting with tamponade. As large pericardial effusions requiring pericardiocentesis are relatively frequent in tuberculous pericarditis, the physician may consider this particular application of ELISpot–TB as a rapid decision aid for starting the treatment.

Long-Term Follow-Up of Previous Hepatitis C Virus Positive Nonresponders to Interferon Monotherapy Successfully Retreated with Combination Therapy: Are They Really Cured?

OBJECTIVES:To evaluate whether in chronic hepatitis C-positive patients who failed to respond to interferon (IFN) monotherapy a sustained response obtained with retreatment using the combination therapy of IFN + ribavirin can be safely considered to reflect eradication of the infection.METHODS:Prospective follow-up of a cohort of 97 patients who responded to retreatment with different regimens of IFN + ribavirin after failing to respond to a first IFN monotherapy course. The patients were followed throughout 7 yr of follow-up with determinations of HCV viremia every 6 months.RESULTS:At the end of the follow-up, 11 patients (11.3%) showed a viremic reappearance. HCV late relapse rates were 0%, 13%, 20%, and 12% in patients retreated, respectively, with 3 MU IFN + ribavirin for 12 months (Group 1), 5 MU IFN + ribavirin for 12 months (Group 2), 3 MU IFN + ribavirin for 6 months (Group 3), and 5 MU IFN + ribavirin for 6 months (Group 4) (Group 2 vs Group 3, p = 0.005).The virologic relapses occurred within 2 yr from therapy withdrawal. Among patients with genotype 1 and 4, the long-term response was significantly higher in Group 2 than in Group 3 (15% vs 3%, p = 0.03). In patients with genotype 2 and 3, the long-term virological response was not affected by the different regimens.CONCLUSIONS:Nonresponders to IFN monotherapy who achieve a sustained virologic response after retreatment with IFN + ribavirin stand a discrete risk of HCV reactivation within 2 yr after therapy.

Insulin resistance in HIV-infected patients: relationship with pro-inflammatory cytokines released by peripheral leukocytes

OBJECTIVES Abnormalities of insulin sensitivity are increasingly reported in HIV infection. Considering that cytokines (particularly TNF-alpha and IL-1beta) can induce insulin resistance in infections, we investigated the relationship between insulin sensitivity and cytokine release from peripheral blood mononuclear cells (PBMCs) in HIV-infected patients. METHODS Fourteen HIV-positive patients treated with dual-NRTI (nucleosidic reverse transcriptase inhibitors) regimens, and fourteen healthy controls were studied. Insulin resistance was assessed by homeostatic model for insulin resistance (HOMA-IR). Cytokine production by PBMCs ex vivo was measured. RESULTS Plasma glucose levels did not differ in HIV patients and in controls. Insulin concentrations and HOMA-IR were significantly higher in HIV-infected patients than in controls (respectively, 11.4+/-4.3 vs. 7.86+/-1.1mIU, P=0.005; 2.27+/-0.91 vs. 1.6+/-0.2, P=0.025). A significant positive linear correlation was observed between HOMA-IR and TNF-alpha concentrations in the supernatants of unstimulated PBMC cultures in HIV patients (r=0.771;P=0.001), but not in controls. CONCLUSIONS Our results are in accordance with previous findings showing that insulin resistance may indeed be present in PI-naive HIV patients, and suggest that either TNF-alpha, or other mediators released in parallel with this cytokine may induce a state of insulin resistance, unrelated to highly active antiviral treatments, in poorly controlled HIV disease.

Validation of a Recombinant Based Antibody ELISA for Diagnosis of Human and Canine Leishmaniasis

Abstract In this study, a recombinant chimeric antigen (CA) ELISA was validated as a single test for both human and dog leishmaniasis. Serum panels included 327 human and 339 canine IFAT-positive and 1113 human and 1078 canine IFAT-negative samples. CA-ELISA was carried out using the same serum dilution, and labelled protein A as secondary reagent. Test performances were calculated using ROC analysis. For the human panel, the test showed diagnostic accuracy (DA) 0.974, specificity (Sp) 97.12%, sensitivity (Se) 91.44%, and concordance (K) 0.88. The dog panel showed DA 0.998, Sp 99.54%, Se 98.54%, and K 0.98. The proposed method is the best recombinant antigen-based ELISA, and can be used as IFAT substitute for mass screening.

Relationship between circulating immune complexes, serum interferon and clinical features in sarcoidosis

In order to assess the importance of circulating interferons and immune complexes as hypothetical mediators of some immune derangements observed in sarcoidosis, we evaluated serum interferon and immune complex levels in 45 patients with active disease. In none of our patients could circulating interferon be detected, suggesting that an infectious (viral) etiology is very unlikely, and that a great difference exists between sarcoidosis and true autoimmune diseases. On the other hand, circulating immune complexes could be found in 64.4% of our patients. A good correlation could be found with disease stage and duration, but only with 67Ga lung scan among other activity indexes.

Effect of erythromycin on the immune response and interferon production

The influence of erythromycin on some aspects of humoral and cell-mediated immunity has been examined employing human as well as murine models, both in vivo and in vitro. No significant differences in antibody synthesis, alpha- and gamma-interferon yield, cutaneous delayed hypersensitivity or lymphocyte blastogenic response to mitogens have been detected between erythromycin-treated subjects and controls. Similarly, in vitro tests on interferon production and blastogenic response to mitogens showed no significant differences when performed with and without erythromycin. Therefore, in contrast with many other antibacterial drugs, erythromycin seems to be devoid of any adverse effects on the immune system.