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Objectives: To compare, using an ex vivo model, the biofilm removal of three surface decontamination methods following surgical exposure of implants failed for severe peri-implantitis. Materials and methods: The study design was a single-blind, randomized, controlled, ex vivo investigation with intra-subject control. Study participants were 20 consecutive patients with at least 4 hopeless implants, in function for >12 months and with progressive bone loss exceeding 50%, which had to be explanted. Implants of each patient were randomly assigned to the untreated control group or one of the three decontamination procedures: mechanical debridement with air-powder abrasion, chemical decontamination with hydrogen peroxide and chlorhexidine gluconate, or combined mechanical-chemical decontamination. Following surgical exposure, implants selected as control were retrieved, and afterwards, test implants were decontaminated according to allocation and carefully explanted with a removal kit. Microbiological analysis was expressed in colony-forming-units (CFU/ml). Results: A statistically significant difference (p < 0.001) in the concentrations of CFU/ml was found between implants treated with mechanical debridement (531.58 ± 372.07) or combined mechanical-chemical decontamination (954.05 ± 2219.31) and implants untreated (37,800.00 ± 46,837.05) or treated with chemical decontamination alone (29,650.00 ± 42,596.20). No statistically significant difference (p = 1.000) was found between mechanical debridement used alone or supplemented with chemical decontamination. Microbiological analyses identified 21 microbial species, without significant differences between control and treatment groups. Conclusions: Bacterial biofilm removal from infected implant surfaces was significantly superior for mechanical debridement than chemical decontamination. Clinical relevance: The present is the only ex vivo study based on decontamination methods for removing actual and mature biofilm from infected implant surfaces in patients with peri-implantitis. [ABSTRACT FROM AUTHOR]

The number of studies which evaluated interferon-gamma release assays (IGRAs) results after anti-tuberculosis (TB) treatment has been rapidly increasing. The aim of this study was to investigate the potential use of IGRAs (QFT-GIT, T-SPOT.TB, QFT-Plus) in assessing the response to anti-TB treatment. We searched all studies in English language published from 1 October 2011 to 18 November 2018 in PubMed, Web of Science, and Scopus. Our search included the term “tuberculosis treatment AND interferon-γ release assay”. We included studies evaluating the performance of commercial IGRAs (including QFT-GIT, T-SPOT.TB and QFT-Plus) before and after the anti-TB treatment. We performed subgroup analysis based on the age (children, adults), type of TB (active, latent, active and latent, and contacts exposed to MDR defined as MDR LTBI), type of IGRAs (QFT-GIT and T-SPOT.TB), and follow-up interval (2, 3, 4, 6, 9 months). Of the 18 included studies, 12 used QFT-GIT for assessment of IGRA performance after therapy, 1 used T-SPOT.TB, and 3 used both QFT-GIT and T-SPOT.TB. Since then, only two studies have assessed the QFT-Plus performance during therapy. According to the results of the meta-analysis, the pooled rate of positive IGRAs (QFT-GIT and T-SPOT.TB) following anti-TB therapy was estimated at 76% [95% CI 70–81%] and no difference was found compared to the pooled positive rate of IGRAs before initiation of therapy which was 76% [95% CI 60–89%]. The subgroup analysis showed that the pooled rate of positive IGRAs (QFT-GIT and T-SPOT.TB) after anti-TB therapy was significantly higher in monitoring active TB subjects [80% (95% CI 74–88%)] than LTBI [71% (95% CI 70–81%)]. Available data are now sufficient to suggest that monitoring changes in the IGRAs (QFT-GIT and T-SPOT.TB) response during anti-TB treatment may have limited use in evaluating the effectiveness of treatment, while the monitoring changes in QFT-Plus during anti-tubercular treatment are recommended to determine treatment efficacy or for treatment monitoring. Further research is needed to establish the efficacy of this new assay as marker on a larger scale for treatment monitoring. [ABSTRACT FROM AUTHOR]

The new QuantiFERON-TB Gold Plus employs modified peptides optimized to elicit an IFNγ response from CD8+ cytotoxic T lymphocytes in addition to CD4+ T cells. With a view to improve the difficult identification of TB cases, we assessed the combination of two specific immunological markers comprising IFNγ secretion and T cells co-expression of CD25 and CD134 in response to Mycobacterium tuberculosis-specific antigens. A total of 34 subjects with suspected TB and 10 age-matched HD were prospectively enrolled. Assessing the performance of QFT-Plus in terms of the TB1 and TB2 results, we found that in TB patients, the quantitative IFNγ value in TB2 was similar to that in TB1, and we did not find any differences irrespective of the disease (pulmonary or extra-pulmonary). The flow cytometric CD25/CD134 assay, allowed a more accurate differentiation between M. tuberculosis-infected and uninfected patients, with a better combination of sensitivity and specificity, especially by evaluation of CD4+ T-cell subset. All individuals with negative QFT-Plus results displayed a positive CD25/CD134 response. Overall, a positive correlation was found between T cells co-expressing CD25/CD134 and IFNγ levels in response to both QFT-Plus TB antigen tubes, as well as between the QFT-Plus TB1 and TB2 tubes. We demonstrated that both TB1 and TB2 induce a higher expression of CD25+CD134+ markers on CD4+ T cells among infected TB subjects, compared to the lower degree of CD8+ T cells, mainly induced to TB2 stimulation. We suggest that a combined use of classic QFT-Plus and specific CD25/CD134 response may be a useful means in the diagnostic workup for active TB. [ABSTRACT FROM AUTHOR]

Conversions and reversions of interferon-gamma (IFN-γ) release assays (IGRAs) were observed when these tests were repeated over time in the same individuals, including those treated with biological agents. In most studies, the variability of IFN-γ plasma levels was not paralleled by clinical change, but a few exceptions exist, in which IGRA conversion predicted the emergence of active tuberculosis (TB). We report the case of a Peruvian patient with rheumatoid arthritis (RA) and Crohn's disease scheduled for treatment with adalimumab. TB screening demonstrated latent TB infection (LTBI), and the patient was started on isoniazid (INH) for 9 months. Adalimumab was initiated after 1 month since INH. QuantiFERON-TB Gold In-Tube, one of the IGRAs currently available, was serially repeated to monitor the status of TB infection during treatment with the biological agent. The patient developed active TB preceded by progressively rising levels of released IFN-γ. We came to know that she had withdrawn INH after 2 months on her own initiative. Considering the low rate of INH completion, serial IGRAs may help in the clinical vigilance during prophylaxis as well as anti-TNF treatment, at least in patients presenting other risk factors aside from the state of immunosuppression. [ABSTRACT FROM AUTHOR]

To ascertain whether multiparametric flow cytometry assessment of multifunctional Mycobacterium tuberculosis ( Mtb)-specific CD4 and CD8 T cells can distinguish between untreated and treated patients with latent tuberculosis infection (LTBI), we enrolled 14 LTBI subjects treated with isoniazid (INH) therapy, 16 untreated LTBI patients, and 25 healthy controls. The analysis of mono-functional CD4 and CD8 T cells producing single cytokines showed significant differences only between uninfected and infected LTBI subjects (both treated and untreated). Conversely, the analysis of multifunctional CD4 T cells revealed a significant reduction in the frequency of two CD4 T cells subsets, those producing IFN-γ, IL-2, and TNF-α simultaneously (triple positive; p = 0.005) and those producing IL-2 alone ( p = 0.0359), as well as a shift towards T cells producing only one cytokine in treated as compared to untreated LTBI subjects. Assigning a triple-positive CD4 T cells a cut-off >0.082 %, 94 % of untreated LTBI patients were scored as positive, as compared to only 28 % of treated LTBI patients and none of the healthy controls. No significant differences between untreated and treated LTBI subjects in terms of Mtb-specific CD8 T cell cytokine profiles ( p > 0.05) were identified. The significant changes in the cytokine profiles of Mtb-specific T cells after INH therapy suggest that analysis of multifunctional T cells may be a promising means for the monitoring of LTBI treatment success. [ABSTRACT FROM AUTHOR]

Mono- and multifunctional specific CD4+ and CD8+ T-cell responses were evaluated to improve the immune-based detection of active tuberculosis (TB) and latent infection (LTBI). We applied flow cytometry to investigate cytokines profile (IFN-γ, TNF-α, and IL-2) of T cells after stimulation with TB antigens in 28 TB-infected subjects (18 active TB and 10 LTBI) and 10 uninfected controls. Cytokines production by CD4+ T cells at single-cell levels was higher in TB-infected subjects than uninfected controls P<0.0001. Assigning to activated CD4+ T cells, producing any of the three cytokines, a cut-off >0.45%, it was possible to differentiate TB-infected (>0.45%) by uninfected subjects (<0.45%). Among TB-infected subjects, the frequencies of multifunctional CD4+ T cells, simultaneously producing all 3 cytokines, are lower in active TB than LTBI subjects P=0.003. Thus, assigning to triple-positive CD4+ T cells a cut-off <0.182%, TB-infected individuals could be classified as active TB subjects (<0.182%) or LTBI subjects (>0.182%). The magnitude of CD8+ T-cell responses showed no differences between active TB and LTBI. Multifunctional CD4+ T-cell responses could have the potential to identify at single time point subjects without TB infection and patients having active or latent TB. [ABSTRACT FROM AUTHOR]

Objectives: Immunotherapy with BCG (Bacille Calmette-Guérin) after transurethral resection of the bladder tumor represents a highly effective primary treatment for intermediate and high-risk superficial bladder cancer. The effectiveness of this therapy has been documented, but its mechanism of action is not clear yet. In the present study, we investigated the changes of dendritic cells (DC) numbers in peripheral blood and urine of patients with superficial bladder cancer undergoing BCG intravescical therapy Material and method: We have enumerated plasmacytoid and myeloid DCs in the peripheral blood and in the urine of patients with bladder cancer in order to clarify the role of these cells in the evolution of the disease and the effect of therapy. DCs in blood and urine samples were assessed using the single-platform TruCOUNT assay with monoclonal antibodies. The study population included 37 healthy donors and 13 patients with diagnosis of primitive superficial bladder cancer. Results: At the time of diagnosis a reduction of blood DCs was found in patients as opposed to healthy donors, while DCs were not found in the urine in the same way as in healthy subjects. Six of these patients were followed before and after weekly and monthly instillations of BCG. In the peripheral blood, we observed an immunological recovery of DCs from the third weekly instillation up to the sixth. In the urine of patients, we didn't find mDCs or pDCs at T0, but we found a statistically significant change from the third instillation up to the sixth. On the contrary, we didn't find mDCs in urine during monthly instillation. Conclusions: DC Count could be used in the monitoring of patients undergoing BCG therapy. Immunological restoration of mDC numbers in peripheral blood and the efflux in urine could be important for confirming the effectiveness of BCG instillation. [ABSTRACT FROM AUTHOR]

Screening for latent tuberculosis infection (LTBI) prior to the prescribing of anti-TNF agents and monitoring for infection during treatment are recommended. The feasibility of novel screening tools, including QuantiFERON-TB Gold In-Tube (QFT-GIT), remains unclear in the setting of immunosuppression. The aim of this study was to evaluate the usefulness of serial QFT-GIT during biologic therapy to assess whether dynamic changes in IFN-γ levels may be helpful in identifying reactivation of LTBI or newly acquired TB. We conducted a prospective study on patient candidates to TNF inhibitors. QFT-GIT was performed at baseline and after 3 and 6 months since biologic onset. A further follow-up period of 6 months was observed. Among patients enrolled ( n = 119; F = 69 %; median age = 47 years, range 18-80), 24 had at least 1 risk factor for LTBI. Ninety-six were taking immunosuppressants at the time of TB testing. At baseline, 5 patients displayed positive, 93 negative, and 21 indeterminate QFT-GIT results. We observed QFT-GIT conversions and reversions in 12 patients with LTBI and in 73 without LTBI. QFT-GIT results changed of 28 % at month 3 and of 21 % at month 6; the greatest change was observed in patients with indeterminate results that became negative (15 %; p < 0.02). No TB cases were detected. In conclusion, the routine use of both QFT-GIT and TST at screening seems not to give any advantage in the setting of patients awaiting biologics. In addition, the feasibility of serial QFT-GIT during biologic therapy needs definition since changes in IFN-γ levels may occur without a pathologic connotation. [ABSTRACT FROM AUTHOR]

Background: Dysregulation of host immune responses plays a critical role in the pathogenesis of severe 2009 pandemic H1N1 infection. Whether H1N1 virus could escape innate immune defense in vivo remains to be investigated. The aim of this study was to evaluate the pattern of innate immune response during human 2009 H1N1 infection. We performed the enumeration of circulating myeloid dendritic cells (mDC) and plasmacytoid DC (pDC) in blood from patients with H1N1 pneumonia shortly after the onset of symptoms and during follow-up at different intervals of time. The analysis of CD4 and CD8 count, CD38 T-cell activation marker and serum cytokine/chemokine plasma levels was also done. Methodology/Principal Findings: Blood samples were collected from 13 hospitalized patients with confirmed H1N1-related pneumonia at time of admission and at weeks 1, 4, and 16 of follow-up. 13 healthy donors were enrolled as controls. In the acute phase of the disease, H1N1-infected patients exhibited a significant depletion in both circulating pDC and mDC in conjunction with a decrease of CD4 and CD8 T cell count. In addition, we found plasmatic hyperproduction of IP-10 and RANTES, whereas increase in T-cell immune activation was found at all time points. When we assessed the changes in DC count over time, we observed a progressive normalization of mDC number. On the contrary, H1N1-infected patients did not achieve a complete recovery of pDC count as values remained lower than healthy controls even after 16 weeks of follow-up. Conclusions: H1N1 disease is associated with a profound depletion of DC subsets. The persistence of pDC deficit for several weeks after disease recovery could be due to H1N1 virus itself or to a preexisting impairment of innate immunity. [ABSTRACT FROM AUTHOR]

Background: In recent years, the impact of antituberculous treatment on interferon (IFN)-c response to Mycobacterium tuberculosis antigens has been widely investigated, but the results have been controversial. The objective of the present study was: i) to evaluate longitudinal changes of IFN-c response to M. tuberculosis-specific antigens in TB patients during antituberculous treatment by using the QuantiFERON-TB Gold (QFT-G) assay; ii) to compare the differences in T-cell response after a short or prolonged period of stimulation with mycobacterial antigens; iii) to assess the CD4+ and CD8+ T cells with effector/memory and central/memory phenotype; iv) to investigate the direct in vitro effects of antituberculous drugs on the secretion of IFN-γ. Principal Findings: 38 TB patients was evaluated at baseline and at month 2 and 4 of treatment and at month 6 (treatment completion). 27 (71%) patients had a QFT-G reversion (positive to negative) at the end of therapy, while 11 (29%) TB patients remained QFT-G positive at the end of therapy. Among the 11 patients with persistent positive QFT-G results, six had a complete response to the treatment, while the remaining 5 patients did not have a resolution of the disease. All 27 patients who became QFT-G negative had a complete clinical and microbiological recovery of the TB disease. In these patients the release of IFN-γ is absent even after a prolonged 6-day incubation with both ESAT-6 and CFP-10 antigens and the percentage of effector/memory T-cells phenotype was markedly lower than subjects with persistent positive QFT-G results. The in vitro study showed that antituberculous drugs did not exert any inhibitory effect on IFN-α production within the range of therapeutically achievable concentrations. Conclusions: The present study suggests that the decrease in the M. tuberculosis-specific T cells responses following successful anti-TB therapy may have a clinical value as a supplemental tool for the monitoring of the efficacy of pharmacologic intervention for active TB. In addition, the antituberculous drugs do not have any direct down-regulatory effect on the specific IFN-γ response. [ABSTRACT FROM AUTHOR]

Background: The clinical application of IFN-c release assays (IGRAs) has recently improved the diagnosis of latent tuberculosis infection. In a multicenter study of the Tuberculosis Network European Trialsgroup (TBNET) we aimed to ascertain in routine clinical practice the accuracy of a novel assay using selected peptides encoded in the mycobacterial genomic region of difference (RD) 1 for the diagnosis of active tuberculosis in comparison with tuberculin skin test (TST), QuantiFERON-TB GOLD In-Tube (Cellestis Ltd., Carnegie, Australia) and T-SPOT.TB (Oxfordimmunotec, Abingdon, UK). Principal Findings: 425 individuals from 6 different European centres were prospectively enrolled. We found that sensitivity of the novel test, TST, QuantiFERON-TB GOLD In-Tube and T-SPOT.TB was respectively 73.1%, 85.3%, 78.1%, and 85.2%; specificity was respectively 70.6%, 48.0%, 61.9% and 44.3%; positive likelihood ratios were respectively 2.48, 1.64, 2.05, and 1.53; negative likelihood ratios were respectively 0.38, 0.31, 0.35, 0.33. Sensitivity of TST combined with the novel test, QuantiFERON-TB GOLD In-Tube and T-SPOT.TB increased up to 92.4%, 97.7% and 97.1%, respectively. The likelihood ratios of combined negative results of TST with, respectively, the novel test, QuantiFERON-TB GOLD In-Tube and T-SPOT.TB were 0.19, 0.07 and 0.10. Conclusions: The assay based on RD1 selected peptides has similar accuracy for active tuberculosis compared with TST and commercial IGRAs. Then, independently of the spectrum of antigens used in the assays to elicit mycobacterial specific immune responses, the novel test, IGRAs, and the TST do not allow an accurate identification of active tuberculosis in clinical practice. However, the combined use of the novel assay or commercial IGRAs with TST may allow exclusion of tuberculosis. [ABSTRACT FROM AUTHOR]

The article discusses the results of the study on the antiviral immune response in patients with multiple sclerosis (MS) which is compared to healthy siblings and twins. It mentions that the study performed on MS-discordant monozygotic (MZ) twins lessens the possibility of inheritable and non-inheritable confounders. It notes that commercially available Epstein-Barr virus (EBV) enzyme immunoassays can be different in performance.