Federica Meloni

Regulatory CD4+CD25+ T cells in the peripheral blood of lung transplant recipients: correlation with transplant outcome.

Background. The subset of CD4+CD25+ regulatory T cells, recently identified in humans, may play a central role in the regulation of immune tolerance to graft survival. Methods. This study assesses the frequency and functional profile of CD4+CD25+CD69− cells in the peripheral blood of lung transplant recipients (>3 years from transplantation), 10 of whom were in a stable clinical condition and 11 of whom demonstrated chronic rejection (bronchiolitis obliterans syndrome). We also studied a group of seven healthy subjects. Results. The frequency of CD4+ T cells expressing CD25 (CD4+CD25+) and the highest levels (CD25high) were lower in patients with bronchiolitis obliterans syndrome compared with healthy subjects and subjects in a stable clinical condition (P ≤0.01). Purified CD4+CD25+ cells exhibited a regulatory functional profile in vitro: they were hyporesponsive, suppressed the proliferation of CD4+CD25− cells, and produced interleukin-10. Conclusion. These results provide in vivo evidence that peripheral CD4+CD25+ T cells may represent an important regulatory subset in lung transplantation.

Correlation of Rhinovirus Load in the Respiratory Tract and Clinical Symptoms in Hospitalized Immunocompetent and Immunocompromised Patients

While human rhinoviruses (HRVs) are well accepted as a major cause of common cold syndromes (rhinitis), their role in the etiology of lower respiratory tract infections is still controversial, and their detection in asymptomatic patients is relatively common. The HRV pathogenic role in four groups of hospitalized patients (pediatric immunocompetent and immunocompromised patients, and adult immunocompetent and immunocompromised patients) was investigated by quantifying HRV load in nasopharyngeal aspirates or bronchoalveolar lavage samples by real‐time reverse transcription PCR (RT‐PCR). Real‐time RT‐PCR was performed in duplicate on all respiratory samples resulting positive by qualitative RT‐PCR. In addition, molecular typing allowed detection of all known HRV species (A, B, and C). In immunocompetent pediatric patients HRVs were mostly associated with lower respiratory tract infections (in the absence of other viral agents) and wheezing, when viral load was ≥106 RNA copies/ml. In young immunocompromised patients (stem cell transplantation recipients), an inverse correlation between HRV persistence over time and time at which the infection occurred after transplantation was observed, whereas in adult immunocompromised patients (lung transplant recipients) HRVs could be detected at a medium–low level (<105 RNA copies/ml) in bronchoalveolar lavage samples taken routinely from asymptomatic patients. In conclusion, when detected at high viral load, HRVs may cause severe upper and lower respiratory tract infections, whereas when detected at a medium–low viral load, an event more frequent in immunocompromised subjects, they may represent only bystander viruses. J. Med. Virol. 81:1498–1507, 2009.

Analysis of bronchoalveolar lavage fluid proteome from systemic sclerosis patients with or without functional, clinical and radiological signs of lung fibrosis

Lung fibrosis is a major cause of mortality and morbidity in systemic sclerosis (SSc). However, its pathogenesis still needs to be elucidated. We examined whether the alteration of certain proteins in bronchoalveolar lavage fluid (BALF) might have a protective or a causative role in the lung fibrogenesis process. For this purpose we compared the BALF protein profile obtained from nine SSc patients with lung fibrosis (SScFib+) with that obtained from six SSc patients without pulmonary fibrosis (SScFib-) by two-dimensional gel electrophoresis (2-DE). Only spots and spot-trains that were consistently expressed in a different way in the two study groups were taken into consideration. In total, 47 spots and spot-trains, corresponding to 30 previously identified proteins in human BALF, showed no significant variation between SScFib+ patients and SScFib- patients, whereas 24 spots showed a reproducible significant variation in the two study groups. These latter spots corresponded to 11 proteins or protein fragments, including serum albumin fragments (13 spots), 5 previously recognized proteins (7 spots), and 4 proteins (3 spots) that had not been previously described in human BALF maps, namely calumenin, cytohesin-2, cystatin SN, and mitochondrial DNA topoisomerase 1 (mtDNA TOP1). Mass analysis did not determine one protein-spot. The two study groups revealed a significant difference in BALF protein composition. Whereas levels of glutathione S-transferase P (GSTP), Cu–Zn superoxide dismutase (SOD) and cystatin SN were downregulated in SScFib+ patients compared with SScFib- patients, we observed a significant upregulation of α1-acid glycoprotein, haptoglobin-α chain, calgranulin (Cal) B, cytohesin-2, calumenin, and mtDNA TOP1 in SScFib+ patients. Some of these proteins (GSTP, Cu–Zn SOD, and cystatin SN) seem to be involved in mechanisms that protect lungs against injury or inflammation, whereas others (Cal B, cytohesin-2, and calumenin) seem to be involved in mechanisms that drive lung fibrogenesis. Even if the 2-DE analysis of BALF did not provide an exhaustive identification of all BALF proteins, especially those of low molecular mass, it allows the identification of proteins that might have a role in lung fibrogenesis. Further longitudinal studies on larger cohorts of patients will be necessary to assess their usefulness as predictive markers of disease.

Systemic inflammatory response and downmodulation of peripheral CD25+Foxp3+ T-regulatory cells in patients undergoing radiofrequency thermal ablation for lung cancer

Radiofrequency thermal ablation (RFTA) is a local tumor-destructing technique that can potentially modulate the host immune response through mechanisms that are not clearly defined. We assessed whether RFTA could affect multiple systemic inflammatory and immunological parameters, including CD25+Foxp+ cells, in patients with primary or metastatic lung tumors. Three days after RFTA, a moderate and temporary systemic inflammatory response developed, as demonstrated by the increase in peripheral neutrophils and monocytes and in plasma levels of proinflammatory chemokines (MIP-1alpha, MIP-1beta, eotaxin, and interleukin[IL]-8) and acute phase reactants (complement C3 and C4, serum amyloid, alpha1 antichymotrypsin, and C-reactive protein). Moreover, we found a concomitant release of the anti-inflammatory factor IL-10. Thirty days after RFTA, a significant reduction in CD25+Foxp3+ counts with an increase in CD4+ T-cell proliferation and number of interferon-gamma-secreting cells was observed. The reduction in CD25+Foxp3+ cells lasted up to 90 days after treatment. The use of RFTA in lung cancer patients has an immunomodulatory activity: it induces a self-limiting systemic inflammation early and later a reduction of circulating CD25+Foxp3+ Tregs. In addition to tumor ablation, downmodulation of this regulatory subset might be an important mechanism involved in the long-term clinical efficacy of RFTA.

Organ Allocation Waiting Time During Extracorporeal Bridge to Lung Transplant Affects Outcomes

BACKGROUND The use of extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplant (LTX) is still being debated. METHODS We performed a retrospective two-center analysis of the relationship between ECMO bridging duration and survival in 25 patients. Further survival analysis was obtained by dividing the patients according to waiting time on ECMO: up to 14 days (Early group) or longer (Late group). We also analyzed the impact of the ventilation strategy during ECMO bridging (ie, spontaneous breathing and noninvasive ventilation [NIV] or intubation and invasive mechanical ventilation [IMV]). RESULTS Seventeen of 25 patients underwent a transplant (with a 76% 1-year survival), whereas eight patients died during bridging. In the 17 patients who underwent a transplant, mortality was positively related to waiting days until LTX (hazard ratio [HR], 1.12 per day; 95% CI, 1.02-1.23; P = .02), and the Early group showed better Kaplan-Meier curves (P = .02), higher 1-year survival rates (100% vs 50%, P = .03), and lower morbidity (days on IMV and length of stay in ICU and hospital). During the bridge to transplant, mortality increased steadily with time. Considering the overall outcome of the bridging program (25 patients), bridge duration adversely affected survival (HR, 1.06 per day; 95% CI, 1.01-1.11; P = .015) and 1-year survival (Early, 82% vs Late, 29%; P = .015). Morbidity indexes were lower in patients treated with NIV during the bridge. CONCLUSIONS The duration of the ECMO bridge is a relevant cofactor in the mortality and morbidity of critically ill patients awaiting organ allocation. The NIV strategy was associated with a less complicated clinical course after LTX.

Cyclosporine in anti-Jo1-positive patients with corticosteroid-refractory interstitial lung disease

Objective. To describe the longterm effectiveness and safety of cyclosporine (CYC) in patients with anti-Jo1-positive antisynthetase syndrome with corticosteroid-refractory interstitial lung disease (ILD). Methods. All patients with anti-Jo1 antisynthetase syndrome referred to our division between June 1991 and February 2010 were retrospectively evaluated for ILD. ILD was assessed using pulmonary function tests (PFT) and/or high-resolution computed tomography (HRCT). Kazerooni score was used to evaluate the HRCT extent of ILD. Prednisone was the first-line treatment in all cases (1 mg/kg/day orally, then tapering). Patients with corticosteroid-refractory or relapsing ILD were then included in this retrospective study. All patients started CYC (3 mg/kg/day) without increasing prednisone dosage. Both PFT and chest HRCT were regularly reassessed during followup. Results. Over the period of study we evaluated 18 patients with antisynthetase syndrome; 17 had ILD (13 women; median age at ILD onset 57 yrs); all patients failed prednisone within 12 months of ILD onset and subsequently started CYC. The median followup on CYC was 96 months [interquartile range (IQR) 57–120 mo]. Upon starting CYC, median forced vital capacity (FVC) was 60% (IQR 56%–70%), median DLCO 60% (IQR 50%–62.75%), and median Kazerooni score 16 (IQR 7–18). After 1 year of CYC, FVC (p = 0.0006), DLCO (p = 0.0010), and total Kazerooni score (p = 0.0002) improved and prednisone was tapered (median reduced from 25 mg/day to 2.5 mg/day; p < 0.0001). The results were substantially maintained including at last available followup. CYC side effects were hypertension (5 patients) and creatinine increase (6 patients). CYC was reduced in 3 cases and withdrawn in 4. Three out of 4 patients who interrupted CYC experienced ILD relapse; 2 patients recommenced low-dose CYC with subsequent ILD control. One patient refused re-treatment and subsequently died. Conclusion. CYC is effective and substantially safe in patients with anti-Jo1 antisynthetase syndrome with corticosteroid-refractory ILD. CYC withdrawal may be associated with ILD relapse, and low-dose CYC was effective in ILD control.

Characteristics of a ferritin-binding protein present in human serum

Summary. The ferritin present in human serum differs from the ferritins found in tissues and other body fluids in having negligible proportions of H subunits. This has been related to the possible presence of binding factors which would form complexes with H‐subunit containing ferritins and thereby determine their rapid clearance and/or interference with immunoassays (serum inhibition’). In this work we have tried to identify and characterize these binding factors. Dotting and blotting experiments demonstrated an interaction between tissue ferritins and human serum. This was stronger with human heart and recombinant H‐type ferritin obtained from E. coli than with human liver ferritin. The serum binder appeared to be a glycoprotein migrating in the beta‐2 region and with a molecular weight of about 200 000 and pi between 4 and 5. Two different approaches to purification of the ferritin‐binding protein yielded enriched fractions containing also the complement proteins C3 and C4, the plasma protease inhibitor alpha‐2‐macroglobulin, and immunoglobulins. These in vitro findings may have physiological relevance.

Efficacy of tacrolimus rescue therapy in refractory acute rejection after lung transplantation

BACKGROUND Encouraging results in transplantation of other solid organs led to investigation of the use of tacrolimus in lung transplantation as a salvage immunosuppressant in persistent acute rejection. METHODS The incidence and severity of acute rejection and the number of steroid pulses were analyzed in 20 lung recipients who were converted from a cyclosporine- to a tacrolimus-based immunosuppressive regimen because of refractory biopsy-proven acute rejection. RESULTS Tacrolimus was started 12.0 +/- 13.0 months after transplantation, and the mean follow-up was 25.0 +/- 13.7 months. After shifting to tacrolimus, a significant decline was observed in both the number of acute rejections per patient (3.0 +/- 1.56 to 0.85 +/- 1.14, p < 0.0001), and the incidence of acute rejection per 100 patient-days (1.52 +/- 0.99 to 0.14 +/- 0.21, p < 0.0001). Furthermore, the average histologic grade of rejection decreased from 1.9 +/- 0.8 to 0.4 +/- 0.5 (p < 0.0001). Methylprednisolone pulses similarly decreased from 1.9 +/- 1.3/patient to 0.3 +/- 0.7/patient (p < 0.0001). During cyclosporine immunosuppression, the mean forced expiratory volume in 1 second decreased to 84.4% +/- 13.3% of individual best value. The average lung function parameters were stable 3 months after the change of medication, and then began to improve. After an average follow-up of 36.5 +/- 19.2 months, 2 patients have developed bronchiolitis obliterans syndrome (one has Stage 1 and one has Stage 3). CONCLUSION Conversion to a tacrolimus-based immunosuppressive regimen for refractory acute lung rejection is associated with reduced incidence and severity of acute rejection episodes, steroid sparing, and stabilization or improvement of pulmonary function.

Acute Chlamydia pneumoniae and Mycoplasma pneumoniae Infections in Community-Acquired Pneumonia and Exacerbations of COPD or Asthma: Therapeutic Considerations

Abstract Rates of acute Chlamydia pneumoniae and Mycoplasma pneumoniae infections were determined in 115 adults hospitalized for community-acquired pneumonia (CAP), purulent exacerbations of COPD and acute exacerbations of bronchial asthma, by means of serology and molecular methods. Results were compared with those obtained in a matched control group. Common respiratory pathogens were isolated by cultures in 22.5% and 22.2% of CAP and exacerbated COPD patients, respectively. Cultures from exacerbated asthma patients were always negative. Serological and molecular evidence of current C. pneumoniae infection was obtained in 10.0%, 8.9% and 3.3% of CAP, COPD and asthma cases. The corresponding rates of acute M. pneumoniae infection were 17.5%, 6.7% and 3.3%, respectively. Finally, no difference was found between typical and atypical pathogen rates. These findings highlight the importance of taking into account C. pneumoniae and M. pneumoniae infections in guiding the choice of empirical antibacterial treatment for CAP and purulent exacerbations of COPD.

Bombesin Enhances Monocyte and Macrophage Activities: Possible Role in the Modulation of Local Pulmonary Defenses in Chronic Bronchitis

Increased lung levels of bombesin-related peptides (BRPs) have been described in smokers and in patients with chronic obstructive pulmonary diseases (COPDs). Moreover, previous studies have shown that BRPs are endowed with immunoregulatory activities. The aim of the present study was to assess the in vitro influence of synthetic bombesin on the activity of mononuclear phagocytes obtained from healthy donors and from COPD patients. Bombesin significantly enhanced in vitro phagocytosis of monocytes and alveolar macrophages in both groups of subjects, restoring deficient phagocytosis in a group of COPD patients. Moreover, bombesin stimulated superoxide anion production and interleukin-8 release by peripheral monocytes.