Relationship between cytokine expression patterns and clinical outcomes: two population-based birth cohorts.

BACKGROUND: Models that incorporate patterns of multiple cytokine responses to allergens, rather than individual cytokine production, may better predict sensitization and asthma. OBJECTIVE: To characterize the patterns of peripheral blood mononuclear cells' (PBMCs) cytokine responses to house dust mite (HDM) allergens among children from two population-based birth cohorts using machine learning techniques. METHODS: PBMCs collected at 8 years of age from the UK Manchester Asthma and Allergy Study (n = 268) and at 14 years of age from the Australian Raine Study (n = 1374) were cultured with HDM extract (10 µg/ml). Cytokine expression (IL-13, IL-5, IFN-γ, and IL10) was measured in the supernatant. Cytokine patterns were identified using a Gaussian mixture model clustering, and classification stability was assessed by bootstrapping. RESULTS: A six-class model indicated complex latent structure of cytokine expression. Based on the characteristics of each class, we designated them as follows: 'Nonresponders' (n = 905, 55%); 'IL-10 responders' (n = 49, 3%); 'IFN-γ and IL-13 medium responders' (n = 56, 3.4%); 'IL-13 medium responders' (n = 351, 21.4%); 'IL-5 and IL-13 medium responders' (n = 77, 4.7%); and 'IL-13 and IL-5 high responders' (n = 204, 12.4%). 'IL-13 and IL-5 high responders' were at much higher risk of HDM sensitization and asthma compared to all other classes, with 88% of children assigned to this class being sensitized and 28.5% having asthma. CONCLUSION: Using model-based clustering, we identified several distinct patterns of cytokine response to HDM and observed interplay between cytokine expression level, cytokine patterns (especially IL-13 and IL-5), and clinical outcomes. 'IL-13 and IL-5 high responders' class was strongly associated with HDM sensitization. However, among HDM-sensitized children, one-third showed no PBMC response to HDM, and the majority of HDM-sensitized children did not have asthma or wheeze. Our findings suggest that positive HDM 'allergy tests' and asthma are associated with a broad range of immunophenotypes, which may have important implications for the use of cytokine-targeted treatment approaches.

Favourable evolution of virological and immunological profiles in treated and untreated patients in Italy in the period 1998-2008.

BACKGROUND: This study provides an estimate of the proportion of HIV-positive patients in Italian clinics showing an 'adverse prognosis' (defined as a CD4 count ≤ 200 cells/µL or an HIV RNA >50 HIV-1 RNA copies/mL) over time, and investigates whether this proportion varied according to patients' characteristics. METHODS: We estimated the annual proportion of patients with a CD4 count ≤ 200 cells/µL or HIV RNA > 50 copies/mL out of the total number of patients in the Icona Foundation cohort seen in any given year, both overall and after stratifying by demographical and treatment status groups. Generalized estimating equation models for Poisson regression were applied. RESULTS: In 1998-2008, the prevalence of patients with a CD4 count ≤ 200 cells/µL decreased from 14 to 6% [adjusted relative risk (RR) 0.86/year; 95% confidence interval (CI) 0.84-0.88; P<0.0001]. The prevalence of HIV RNA > 50 copies/mL decreased from 66 to 40% (adjusted RR 0.95/year; 95% CI 0.95-0.96; P<0.0001) in all patients and from 38 to 12% in the subgroup of patients who had previously received antiretroviral therapy (ART) for ≥ 6 months (adjusted RR 0.89/year; 95% CI 0.88-0.90; P<0.0001). CONCLUSIONS: There was a substantial increase in the success rate of ART in Italy in 1998-2008, resulting in a lower percentage of patients with adverse prognosis in recent years. The use of ART seemed to be the most important determinant of viral load outcome, regardless of mode of transmission. Although injecting drug users showed a less marked improvement in CD4 cell count over time than other risk groups, they showed a similar improvement in detectable viral load.

Incidence of malignancies in HIV-infected patients and prognostic role of current CD4 cell count: evidence from a large Italian cohort study.

The incidence of and predictors of acquired immunodeficiency syndrome-defining malignancies (ADMs) and non-ADM (NADMs) were evaluated in a large Italian cohort. The incidence of ADM and NADM was 5.0 cases per 1000 person-years of follow-up (95% confidence interval, 4.3-5.8 cases per 1000 person-years of follow-up) and 2.4 cases per 1000 person-years of follow-up (95% confidence interval, 1.9-3.1 cases per 1000 person-years of follow-up), respectively. Lower current CD4 cell count was an independent predictor of developing malignancies, with the association being stronger for ADM than for NADM.