Expression of gut-homing ß7 receptor on T cells: surrogate marker for microbial translocation in suppressed HIV-1-infected patients?

OBJECTIVES: In view of the fact that mucosal damage associated with HIV-1 infection leads to microbial translocation despite successful antiretroviral treatment, we analysed microbial translocation and expression of the gut-homing ß7 receptor on peripheral T cells in HIV-1-infected individuals. METHODS: Fifteen long-term suppressed HIV-1-infected patients, of whom seven had their treatment intensified with maraviroc and eight with raltegravir, were included in the study. Samples at baseline, at week 48 of intensification, and at weeks 12 and 24 after deintensification were analysed for soluble CD14, lipopolysaccharide (LPS), LPS-binding protein, gut-homing ß7 receptor and T-cell subsets. RESULTS: The increases in both microbial translocation and expression of the gut-homing ß7 receptor on activated CD8 T cells found during maraviroc intensification were reduced after deintensification. Moreover, the correlations between activated ß7(+) T cells and LPS levels found during intensification with maraviroc (P = 0.036 and P = 0.010, respectively) were lost during deintensification. In contrast, microbial translocation was stable during raltegravir intensification, with the exception of decreased LPS levels and activated CD4 ß7(+) T cells, which reverted to baseline values after deintensification. CONCLUSIONS: Microbial translocation is an important factor in gut immune activation and mucosa inflammation, as evidenced by the association between the dynamics of microbial translocation and activated T cells expressing the gut-homing ß7 receptor. The recruitment of activated ß7(+) T cells to the gut tract when alteration of microbial translocation is maximum may be the major mechanism for recovery of mucosal integrity.

Interpreting the reasons for the choice and changing of two drug regimens in an observational cohort: comparison of a ritonavir-boosted protease inhibitor-based versus a nonnucleoside reverse transcriptase inhibitor-based first-line regimen.

OBJECTIVES: We compared reasons for the choice of regimen, time to and reasons for third drug modification, virological response and change in CD4 T-cell counts in patients started on atazanavir/ritonavir (ATV/r)- vs. efavirenz (EFV)-based first-line regimens. METHODS: We included patients from the Cohort of the Spanish HIV Research Network (CoRIS), a multicentre cohort of HIV-positive treatment-naïve subjects, in the study. We used logistic regression to assess factors associated with choosing ATV/r vs. EFV, proportional hazards models on the subdistribution hazard to estimate subdistribution hazard ratios (sHRs) for third drug modification, logistic regression to estimate odds ratios (ORs) for virological response and linear regression to assess mean differences in CD4 T-cell count increase from baseline. RESULTS: Of 2167 patients, 10.7% started on ATV/r. ATV/r was more likely than EFV to be prescribed in injecting drug users [adjusted OR 1.85; 95% confidence interval (CI) 1.03-3.33], in 2009-2010 (adjusted OR 1.63; 95% CI 1.08-2.47) and combined with abacavir plus lamivudine (adjusted OR 1.53; 95% CI 0.98-2.43). Multivariate analyses showed no differences, comparing ATV/r vs. EFV, in the risk of third drug modification (sHR 1.04; 95% CI 0.74-1.46) or in virological response (OR 0.81; 95% CI 0.46-1.41); differences in mean CD4 T-cell count increase from baseline were at the limit of statistical significance (mean difference 29.8 cells/µL; 95% CI -4.1 to 63.6 cells/µL). In patients changing from EFV, 48% of changes were attributable to toxicity/adverse events, 16% to treatment failure/resistance, 3% to simplification, and 8 and 12%, respectively, to patients' and physicians' decisions; these percentages were 24, 6, 12, 14 and 24%, respectively, in those changing from ATV/r. CONCLUSIONS: ATV/r- and EFV-based regimens meet the requirements of both efficacy and safety for initial combination antiretroviral regimen, which relate to better durability.

Comparison of antiviral activity of regimens containing nucleos(t)ide (NUC) Pairs in HIV-Infected Patients Initiating REScue therapy (The NUCREST Study).

BACKGROUND: recycling nucleos(t)ides (NUCs) is useful in regions where new antiretrovirals are not available. This study compares the effectiveness of NUC-containing regimens as rescue therapy in routine care. METHODS: retrospective, multicentre cohort study (January 2001 to June 2006) of patients with ≥ 1 virological failure who started therapy with 2 NUCs and 1 non-nucleoside reverse transcriptase inhibitor (NNRTI) or a protease inhibitor (PI). The primary endpoint was the rate of treatment response at 6 months (intention-to-treat [ITT] analysis). RESULTS: we included 719 patients (average of 4 prior regimens over a median 6.1 years). The most frequent NUC pairs were tenofovir plus lamivudine (TDF+3TC; 25%), tenofovir plus stavudine (TDF+d4T; 23%), and stavudine plus didanosine (d4T+ddI; 15%). A boosted PI was used in 68% of total cases. Resistance to both NUCs was more frequent in zidovudine plus lamivudine (AZT+3TC; 22.0%), abacavir plus lamivudine (ABC+3TC; 35.5%), and stavudine plus lamivudine (d4T+3TC; 31.2%). No significant differences were observed in treatment response (overall 65%, P = .67); ddI+3TC (71%) and d4T+3TC (53%) had the highest and lowest response rates, respectively. Median time to failure was shorter with d4T+3TC, d4T+ddI, and ABC+3TC (48, 51, and 58 weeks, respectively; P = .0012). Lower response rates associated with an increasing number of thymidine analog mutations (TAMs) were observed for ABC+3TC (P = .027). CONCLUSION: the clinical utility of NUCs for rescue therapy is limited and selection should be individualized. Specific combinations (d4T+3TC and d4T+ddI) might be less efficacious.

[Laboratory diagnosis and serologic course in patients with tularemia]. / Diagnóstico de laboratorio y evolución serológica de pacientes con tularemia.

BACKGROUND: Tularemia was practically unknown in Spain until the end of 1997, when an epidemic outbreak was declared. This paper presents the data on microbiological diagnosis of 55 patients who suffered from tularemia. PATIENTS AND METHODS: Thirty-two samples from 19 patients and 151 serum samples from 55 patients were obtained for culture. Serologic diagnosis was performed by tube sero-agglutination and microagglutination. Three types of tests were performed on all sera: Wright sero-agglutination (WSA), Coombs test against Brucella spp. and sero-agglutination against Yersinia enterocolitica O:3, Yersinia enterocolitica O:3, and Proteus OX 19. RESULTS: F. tularensis was found in two samples (6.25%) of the 32 received. Titers > or = 1/160 were obtained in 78.2% and 74.5% of the initial sera by tube sero-agglutination and microagglutination, respectively. Correlation between the two tests was 0.80 (p < 0.001). Prozone phenomenon was observed in 59.9% of the sera, while crossed reactivity to Brucella spp. and Proteus spp. was found in 9.3% and 22.8%, respectively. No crossed reactivity was observed with Yersinia spp. CONCLUSIONS: Culture of F. tularensis has low sensitivity. The correlation obtained between tube sero-agglutination and microagglutination is good. Both techniques are useful in routine diagnosis of tularemia, although microagglutination has some advantages over tube agglutination.

Human Papillomavirus (HPV) Genotyping: Automation and Application in Routine Laboratory Testing.

A large number of assays designed for genotyping human papillomaviruses (HPV) have been developed in the last years. They perform within a wide range of analytical sensitivity and specificity values for the different viral types, and are used either for diagnosis, epidemiological studies, evaluation of vaccines and implementing and monitoring of vaccination programs. Methods for specific genotyping of HPV-16 and HPV-18 are also useful for the prevention of cervical cancer in screening programs. Some commercial tests are, in addition, fully or partially automated. Automation of HPV genotyping presents advantages such as the simplicity of the testing procedure for the operator, the ability to process a large number of samples in a short time, and the reduction of human errors from manual operations, allowing a better quality assurance and a reduction of cost. The present review collects information about the current HPV genotyping tests, with special attention to practical aspects influencing their use in clinical laboratories.

Effect of food on the antiviral activity of didanosine enteric-coated capsules: a pilot comparative study.

OBJECTIVES: To determine the effect of food on the antiviral activity of enteric-coated (EC) capsules of didanosine (ddI). METHODS: We conducted a pilot, randomized, open-label study of 28-day ddI-EC capsules monotherapy-administered in a fasted state (group 1, n=11) or with food (group 2, n=10) to treatment-naïve chronically HIV-1-infected individuals. To assess the antiviral efficacy, HIV-1 RNA was determined at baseline, day 3, day 7 and weekly thereafter. The area under the HIV-1 RNA curve minus baseline weighted by time (AUCMB/day) was calculated. RESULTS: Mean baseline HIV-1 RNA was 4.2 log(10) copies/mL in group 1 and 3.8 log(10) copies/mL in group 2. After 28 days, the mean HIV-1 RNA reduction was 0.99 log(10) copies/mL [95% confidence interval (CI) 0.45-1.53] for group 1 and 0.89 log(10) copies/mL (95% CI 0.38-1.40) for group 2. AUCMB/day values were 0.775 log(10) copies/mL (95% CI 0.33-1.22) and 0.774 log(10) copies/mL (95% CI 0.48-1.07), respectively, showing no difference in the rate of decrease of HIV-1 RNA (P=0.995). Mean ddI plasma levels at day 28 were 0.0234 mg/L for group 1 and 0.0227 mg/L for group 2 (P=0.96). CONCLUSIONS: In this pilot study, the administration of food did not have any significant effect on the antiviral activity of ddI-EC capsules.