Association between Patient Acceptable Symptom State and disease activity in psoriatic arthritis is disrupted by confounders, including comorbid fibromyalgia.

OBJECTIVES: Due to the prevalence of fibromyalgia in psoriatic arthritis (PsA) patients, any evaluation about PsA-specific patient-reported outcomes (PROs) should take in account the possible bias related to this comorbidity. Patient acceptable symptom state (PASS) is a patient-reported measure evaluating the acceptable and/or satisfactory level of symptoms in rheumatic diseases, which has been proposed as a disease activity index, in patients with PsA. Thus, this study was designed to analyse if the association between PASS and PsA disease activity may be biased by the presence of comorbid fibromyalgia. METHODS: A multi-centre, cross-sectional, observational study enrolling consecutive PsA participants has been conducted from July 2021 to November 2021. The Disease Activity for Psoriatic Arthritis (DAPSA) was collected; the following formulation of PASS question: 'Think about all the ways your PsA has affected you during the last 48 hours. If you were to remain in the next few months as you were during the last 48 hours, would this be acceptable to you?', was submitted to our participants. RESULTS: Multivariable logistic regressions, adjusted for the presence of fibromyalgia, did not show any significant association between PASS and DAPSA low disease activity, DAPSA as nominal variable (remission, low disease activity, moderate disease activity, high disease activity) and DAPSA as continuous variable. CONCLUSIONS: Our data suggest that fibromyalgia influences the patient's perception of the disease and has a negative impact on PASS status independently of disease activity, thus limiting the utility of this Patient reported outcome in real world clinical practice.

Autoantibody status according to multiparametric assay accurately estimates connective tissue disease classification and identifies clinically relevant disease clusters.

OBJECTIVE: Assessment of circulating autoantibodies represents one of the earliest diagnostic procedures in patients with suspected connective tissue disease (CTD), providing important information for disease diagnosis, identification and prediction of potential clinical manifestations. The purpose of this study was to evaluate the ability of multiparametric assay to correctly classify patients with multiple CTDs and healthy controls (HC), independent of clinical features, and to evaluate whether serological status could identify clusters of patients with similar clinical features. METHODS: Patients with systemic lupus erythematosus (SLE), systemic sclerosis (SSc), Sjogren's syndrome (SjS), undifferentiated connective tissue disease (UCTD), idiopathic inflammatory myopathies (IIM) and HC were enrolled. Serum was tested for 29 autoantibodies. An XGBoost model, exclusively based on autoantibody titres was built and classification accuracy was evaluated. A hierarchical clustering model was subsequently developed and clinical/laboratory features compared among clusters. RESULTS: 908 subjects were enrolled. The classification model showed a mean accuracy of 60.84±4.05% and a mean area under the receiver operator characteristic curve of 88.99±2.50%, with significant discrepancies among groups. Cluster analysis identified four clusters (CL). CL1 included patients with typical features of SLE. CL2 included most patients with SjS, along with some SLE and UCTD patients with SjS-like features. CL4 included anti-Jo1 patients only. CL3 was the largest and most heterogeneous, including all the remaining subjects, overall characterised by low titre or lower-prevalence autoantibodies. CONCLUSION: Extended multiparametric autoantibody assay allowed an accurate classification of CTD patients, independently of clinical features. Clustering according to autoantibody titres is able to identify clusters of CTD subjects with similar clinical features, independently of their final diagnosis.

The specialized pro-resolving lipid mediator Protectin D1 affects macrophages differentiation and activity in Adult-onset Still's disease and COVID-19, two hyperinflammatory diseases sharing similar transcriptomic profiles.

Introduction: COVID-19 and autoinflammatory diseases, such as Adult-onset Still's Disease (AOSD), are characterized by hyperinflammation, in which it is observed massive production and uncontrolled secretion of pro-inflammatory cytokines. The specialized pro-resolving lipid mediators (SPMs) family is one the most important processes counteracting hyperinflammation inducing tissue repair and homeostasis restoration. Among SPMs, Protectin D1 (PD1) is able to exert antiviral features, at least in animal models. The aim of this study was to compare the transcriptome of peripheral blood mononuclear cells (PBMCs) from patients with AOSD and COVID-19 and to evaluate the role of PD1 on those diseases, especially in modulating macrophages polarization. Methods: This study enrolled patients with AOSD, COVID-19, and healthy donors HDs, undergoing clinical assessment and blood sample collection. Next-generation deep sequencing was performed to identify differences in PBMCs transcripts profiles. Plasma levels of PD1 were assessed by commercial ELISA kits. Monocyte-derived macrophages were polarized into M1 and M2 phenotypes. We analyzed the effect of PD1 on macrophages differentiation. At 10 days, macrophages were analyzed for surface expression of subtypes markers by flow cytometry. Cytokines production was measured in supernatants by Bio-Plex Assays. Results: In the transcriptomes from AOSD patients and COVID-19 patients, genes involved in inflammation, lipid catabolism, and monocytes activation were specifically dysregulated in AOSD and COVID-19 patients when compared to HDs. Patients affected by COVID-19, hospitalized in intensive care unit (ICU), showed higher levels of PD1 when compared to not-ICU hospitalized patients and HDs (ICU COVID-19 vs not-ICU COVID-19, p= 0.02; HDs vs ICU COVID-19, p= 0.0006). PD1 levels were increased in AOSD patients with SS ≥1 compared to patients with SS=0 (p=0.028) and HDs (p=0.048). In vitro treatment with PD1 of monocytes-derived macrophages from AOSD and COVID-19 patients induced a significant increase of M2 polarization vs control (p<0.05). Furthermore, a significant release of IL-10 and MIP-1ß from M2 macrophages was observed when compared to controls (p<0.05). Discussion: PD1 is able to induce pro-resolutory programs in both AOSD and COVID-19 increasing M2 polarization and inducing their activity. In particular, PD1-treated M2 macrophages from AOSD and COVID-19 patients increased the production of IL-10 and enhanced homeostatic restoration through MIP-1ß production.

Interstitial Lung Disease and Pulmonary Damage in Primary Sjögren's Syndrome: A Systematic Review and Meta-Analysis.

BACKGROUND: Pulmonary lung involvement is the most common extra-glandular manifestation in patients with primary Sjögren's syndrome (pSS), leading to a worsening of the patient's prognosis. To date, different studies have assessed the prevalence of pulmonary involvement and interstitial lung disease (ILD) in pSS patients with different results. METHODS: We performed a systematic literature review and meta-analysis on ILD pooled prevalence in pSS according to the PRISMA and MOOSE guidelines. Furthermore, we explored the pooled prevalence of the two main presentations of pSS-ILD, nonspecific interstitial pneumonia (NSIP) and usual interstitial pneumonia (UIP). RESULTS: We analysed the pSS-ILD prevalence in 30 studies including 8255 pSS patients. The pSS-ILD pooled prevalence was 23% (95% CI: 16-30). For NSIP, we found a pooled prevalence of 52% (CI 41-64), and for UIP we found a pooled prevalence of 44% (CI: 32-55). Regarding the meta-regression analysis, male gender, DLco value, country, and HRCT seem to contribute to the ILD presence. CONCLUSIONS: At least 20% of pSS patients have a comorbid ILD, usually NSIP. Male gender and alteration in DLco value may be considered the most important independent factors supporting an active search of lung complications during the clinical history of pSS patients.

The similar expression of both ferritin and scavenger receptors activation genes in patients with COVID19 and AOSD support their role in the pathogenesis of these diseases and identify a common mechanism at the basis of the "hyperferritinemic syndromes".

A role for COVID19 in "hyperferritinemic syndromes" has been proposed based on its clinical and serological characteristics and its similarities with AOSD. To better understand the molecular pathways responsible of these similarities, we evaluated in the PBMCs of 4 active AOSD patients, 2 COVID19 patients with ARDS, and 2 HCs the expression of genes associated with iron metabolisms, with monocyte/macrophages activation, and finally with NETs formation.

Multiparametric autoantibody analysis: a new paradigm for the diagnosis of connective tissue diseases.

BACKGROUND: In patients affected by connective tissue diseases (CTDs), the identification of wide autoantibody profiles may prove useful in early diagnosis, in the evaluation of prognosis (risk stratification), and in predicting response to therapy. The aim of the present study was to evaluate the utility of multiparametric autoantibody analysis performed by a new fully automated particle-based multi-analyte technology (PMAT) digital system in a large multicenter cohort of CTD patients and controls. METHODS: Serum samples from 787 patients with CTD (166 systemic lupus erythematosus; 133 systemic sclerosis; 279 Sjögren's syndrome; 106 idiopathic inflammatory myopathies; 103 undifferentiated CTD), 339 patients with other disorders (disease controls) (118 infectious diseases, 110 organ-specific autoimmune diseases, 111 other rheumatic diseases), and 121 healthy subjects were collected in 13 rheumatologic centers of the FIRMA group. Sera were analyzed with the Aptiva-PMAT instrument (Inova Diagnostics) for a panel of 29 autoantibodies. RESULTS: Multiparametric logistic regression showed that enlarged antibody profiles have a higher diagnostic efficiency than that of individual antibodies or of antibodies that constitute classification criteria for a given disease and that probability of disease increases with multiple positive autoantibodies. CONCLUSIONS: This is the first study that analyzes the clinical and diagnostic impact of autoantibody profiling in CTD. The results obtained with the new Aptiva-PMAT method may open interesting perspectives in the diagnosis and sub-classification of patients with autoimmune rheumatic diseases.

Real-life survey on severe asthma patients during COVID-19 lockdown in Italy.

Introduction: The SARS-CoV-2 pandemic has deeply revolutionized our lives and consequently the management of patients, specifically ones with severe asthma.Objective: A survey was conducted to evaluate the effects on adherence, exacerbations and quality of life in patients with severe asthma during the COVID-19 pandemic period.Methods: 100 severe asthma patients, who accepted to participate to the survey, were asked to respond to different questionnaires in order to assess asthma symptoms (Asthma Control Test - ACT, and Asthma Control Quality - ACQ) and rino-sinusal ones (Sino-nasal outcome test - SNOT-22).Results: 31 out of 100 patients reported worsening of respiratory symptoms requiring a step-up in therapy dosage or frequency during the observational period; however, exacerbation rate was very low. Only 17 (17%) of the 100 participants experienced a severe asthma exacerbation. Moreover, there was no confirmed diagnosis of COVID-19 in this population.Conclusion: Patients with severe asthma did not show higher rates of exacerbations during the pandemic outbreak as well as no increased risk of contracting COVID-19 infection or developing the disease. Self-administration of biological drugs could be useful to maintain high rates of adherence to therapy, and, at the same time, to decrease the risk of exacerbations or Intensive Care Unit (ICU) room access.

Clinical comparison of QUANTA Flash dsDNA chemiluminescent immunoassay with four current assays for the detection of anti-dsDNA autoantibodies.

INTRODUCTION: The objective of the present study was to compare QUANTA Flash dsDNA, a chemiluminescent immunoassay (CIA) on the BIO-FLASH, a rapid-response chemiluminescent analyzer, to three other anti-dsDNA antibody assays and to Crithidia luciliae indirect immunofluorescence test (CLIFT). METHODS: In the first part of the study, 161 samples, 61 from patients suffering from systemic lupus erythematosus (SLE) and 100 from a disease control group, were tested by QUANTA Flash dsDNA CIA, QUANTA Lite dsDNA SC ELISA, BioPlex 2200 multiplex flow immunoassay (MFI), ImmuLisa dsDNA ELISA, and NOVA Lite CLIFT. A second cohort of 69 SLE patients was then tested by QUANTA Flash dsDNA and CLIFT to expand the study. RESULTS: The overall qualitative agreements varied between 77.0% (NOVA Lite CLIFT versus QUANTA Lite) and 89.4% (ImmuLisa versus NOVA Lite CLIFT). The clinical sensitivities for the anti-dsDNA antibody tests varied from 8.2% (NOVA Lite CLIFT) to 54.1% (QUANTA Lite), while the clinical specificities varied from 88.0% (BioPlex 2200) to 100.0% (NOVA Lite CLIFT). Good correlation was found between QUANTA Flash dsDNA and NOVA Lite CLIFT. CONCLUSION: Significant variations among dsDNA methods were observed. QUANTA Flash dsDNA provides a good combination of sensitivity and specificity for the diagnosis of SLE and good agreement to CLIFT.

The classification of Crithidia luciliae immunofluorescence test (CLIFT) using a novel automated system.

INTRODUCTION: In recent years, there has been an increased demand for computer-aided diagnosis (CAD) tools to support clinicians in the field of indirect immunofluorescence. To this aim, academic and industrial research is focusing on detecting antinuclear, anti-neutrophil, and anti-double-stranded (anti-dsDNA) antibodies. Within this framework, we present a CAD system for automatic analysis of dsDNA antibody images using a multi-step classification approach. The final classification of a well is based on the classification of all its images, and each image is classified on the basis of the labeling of its cells. METHODS: We populated a database of 342 images--74 positive (21.6%) and 268 negative (78.4%)-- belonging to 63 consecutive sera: 15 positive (23.8%) and 48 negative (76.2%). We assessed system performance by using k-fold cross-validation. Furthermore, we successfully validated the recognition system on 83 consecutive sera, collected by using different equipment in a referral center, counting 279 images: 92 positive (33.0%) and 187 negative (67.0%). RESULTS: With respect to well classification, the system correctly classified 98.4% of wells (62 out of 63). Integrating information from multiple images of the same wells recovers the possible misclassifications that occurred at the previous steps (cell and image classification). This system, validated in a clinical routine fashion, provides recognition accuracy equal to 100%. CONCLUSION: The data obtained show that automation is a viable alternative for Crithidia luciliae immunofluorescence test analysis.

Leptin, adiponectin and vascular stiffness parameters in women with systemic lupus erythematosus.

The purpose of the present study was to determine levels of adipokines and their relationship with stiffness parameters and disease activity index in SLE patients in comparison with healthy controls. Sixty SLE patients and 29 control subjects were enrolled in the study. Serum leptin and adiponectin levels were determined by commercial sandwich ELISA kits. Colour-coded carotid duplex sonography was performed using a Siemens SONOLINE Antares machine equipped with linear 5-13 MHz. SLEDAI, ECLAM and SLICC were evaluated in all patients. Data were analysed by software for statistical analysis (Prism 5.0). Median leptin is higher among SLE patients compared with controls (p 0.035). Median values of vascular stiffness and PSEM are increased in SLE compared with controls (p = 0.0003 and p = 0.007). Vascular strain and vascular distensibility are lower in SLE patients in comparison with controls (p = 0.0001 and p = 0.0006, respectively). Considering SLE patients, leptin levels correlate with vascular stiffness (r = 0.64, p < 0.0001) and PSEM (r = 0.63, p < 0.0001). Adiponectin levels correlate with vascular strain (r = 0.28, p 0.039) and negatively correlate with vascular stiffness (r = -0.38, p 0.039). Leptin levels correlate with disease activity (SLEDAI and ECLAM) and cumulative damage (SLICC) indexes. This study demonstrates higher values of leptin in SLE patients. Moreover, SLE patients show increased levels of vascular stiffness and PSEM and reduced values of vascular strain and distensibility. These results globally indicate a decline in arterial elasticity. We find a positive correlation of leptin with stiffness parameters. According to its atheroprotective action, adiponectin inversely correlates with stiffness parameters.

Novel opportunities in automated classification of antinuclear antibodies on HEp-2 cells.

The recommended method for antinuclear antibodies (ANA) detection is IIF but it is influenced by many different factors. In order to pursue a high image quality without artefacts and to reduce inter-observer variability, this study aims to evaluate the reliability of using automatically acquired digital images for diagnostic purposes. In this paper we present SLIM-system a comprehensive system that supports the two sides of IIF tests classification. It is based on two systems: the first labels the fluorescence intensity, whereas the second recognizes the staining pattern of positive wells. We populated a dataset of 600 images obtained from sera screened for ANA by IIF on Hep-2 cells. The error rate has been evaluated according to eight-fold cross validation method; the rates reported in the following are the mean of the tests. Performance of the system in positive/negative recognition ranges from 87% up to more than 94%. Staining pattern classification accuracy of main classes ranges from 71% to 74%. The system provides high and reliable identification of negative samples and a flexibility that permits to use this application for different purposes. The analysis of its perspective performance shows the system potential in lowering the method variability, in increasing the level of standardization and in reducing the specialist workload of more than 80%. Our data represent a first step to validate the use of Computer Aided Diagnosis (CAD), thus offering an opportunity for standardizing and automatizing the detection of ANA by IIF.

Angiogenic cytokines in patients undergoing antiviral treatment for chronic hepatitis C virus infection.

During chronic liver disease (CLD), angiogenesis participates in the fibrogenic process. Herein, we aimed at verifying the on-treatment kinetics of serum vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang-2) in hepatitis C virus (HCV) patients undergoing antiviral therapy. Forty-three HCV patients treated with pegylated-interferon/ribavirin and 26 controls were studied. Serum VEGF and Ang-2 were determined before treatment, at different time points during treatment, and at follow-up after treatment. Thirty and 13 patients were sustained virological responder (SVR) and No-SVR, respectively. Patients showed increased Ang-2 levels [504 (368-720) versus 449 (389-483) pg/mL, P < 0.05], and equivalent VEGF levels [271 (193-377) versus 274 (199-324) pg/mL, P = 0.6], with respect to controls. By univariate analysis, stage of fibrosis was associated with Ang-2 levels (odds ratio 4.25, P < 0.05). In SVR patients VEGF levels showed a progressive reduction (P < 0.05) but returned to pretherapy levels at follow-up, and Ang-2 levels showed an opposite progressive increase, being significantly reduced at follow-up (P < 0.01). No significant modifications in VEGF and Ang-2 levels were observed in No-SVR. We conclude that, in patients with HCV-CLD, Ang-2 serum levels are associated with fibrosis and reduced at follow-up in SVR patients. On-treatment, VEGF and Ang-2 serum levels undergo different-sided modifications only in SVR patients, possibly expressing the vascular remodeling occurring early after viral clearance.

Adipokines and systemic lupus erythematosus: relationship with metabolic syndrome and cardiovascular disease risk factors.

OBJECTIVE: To study concentrations of adipokines in patients with systemic lupus erythematosus (SLE) and the relationship among adipokines, the metabolic syndrome (MeS), and cardiovascular disease (CVD) risk factors. METHODS: We enrolled 50 SLE patients and 26 controls, all women. Leptin, resistin, visfatin, and adiponectin were measured by commercial ELISA kits. RESULTS: MeS prevalence was increased among subjects with SLE. Leptin levels were higher in patients with SLE than controls. Among SLE patients, independent determinants of leptin were insulin levels (p < 0.0001), triglycerides (p = 0.03), body mass index (p = 0.02), corticosteroid dosage (p = 0.02), and SLE Disease Activity Index (p = 0.005). Other adipokines did not differ between SLE patients and controls. CONCLUSION: Leptin was increased in SLE patients and could play a role in SLE-related cardiovascular diseases.

Indirect immunofluorescence in autoimmune diseases: assessment of digital images for diagnostic purpose.

BACKGROUND: The recommended method for antinuclear antibodies (ANA) detection is indirect immunofluorescence (IIF). To pursue a high image quality without artefacts and reduce interobserver variability, this study aims at evaluating the reliability of automatically acquired digital images of IIF slides for diagnostic purposes. METHODS: Ninety-six sera were screened for ANA by IIF on HEp-2 cells. Two expert physicians looking at both the fluorescence microscope and the digital images on computer monitor performed a blind study to evaluate fluorescence intensity and staining pattern. Cohen's kappa was used as an agreement evaluator between methods and experts. RESULTS: Considering fluorescence intensity, there is a substantial agreement between microscope and monitor analysis in both physicians. Agreement between physicians was substantial at the microscope and perfect at the monitor. Considering IIF pattern, there was a substantial and moderate agreement between microscope and monitor analysis in both physicians. Kappa between physicians was substantial both at the microscope and at the monitor. CONCLUSIONS: These preliminary results suggest that digital media is a reliable tool to help physicians in detecting autoantibodies in IIF. Our data represent a first step to validate the use of digital images, thus offering an opportunity for standardizing and automatizing the detection of ANA by IIF.

Auditory pathway in rheumatoid arthritis. A comparative study and surgical perspectives.

CONCLUSION: Rheumatoid arthritis (RA) patients present with both conductive and sensorineural deafness. OBJECTIVE: To evaluate the prevalence and features of hearing impairment in patients with RA. MATERIAL AND METHODS: A total of 28 RA patients underwent a rheumatological evaluation, including determination of rheumatoid factor, protein 2-glycoprotein I level and the Lee index. An audiological assessment consisting of pure-tone audiometry (PTA) and determination of auditory brainstem responses (ABRs) and transient evoked otoacoustic emissions (TEOAEs) was performed. The results were compared with those of 28 age- and sex-matched healthy subjects. Four selected RA patients underwent stapedectomy; PTA and TEOAEs were evaluated 6 months postoperatively. RESULTS: Increased air conduction thresholds at 250, 500 and 1000 Hz were found in RA subjects in comparison to controls (p<0.001). RA patients showed higher air-bone gaps in PTA (p<0.05) and an increased Wave I latency in ABRs (p=0.03). Decreased reproducibility (p<0.001) and amplitude (p<0.001) of TEOAEs were found in RA subjects in comparison to controls. A significant correlation between disease duration and echo amplitude was noticed (r=0.389). After stapedectomy, a reduction in the air-bone conduction gap (11 vs 2 dB HL) was noticed; no significant difference in TEOAEs was found.

Anti-lactoferrin antibodies in systemic lupus erythematosus: isotypes and clinical correlates.

Lactoferrin (LF) is a multifunctional iron-binding protein present in several mucosal secretions as well as in secondary granules of polymorphonuclear leukocytes (PMN). Anti-LF antibodies, which belong to antineutrophil cytoplasmic antibodies (ANCA), have been described in several immunomediated diseases, including systemic lupus erythematosus (SLE), with conflicting results regarding either their prevalence or clinical associations. We studied the prevalence and isotype distribution of anti-LF and their association with clinical manifestations, disease activity, and other autoantibodies in 97 patients (83 women) affected by SLE. Anti-LF were detected by enzyme-linked immunosorbent assay. Disease activity was assessed using the Systemic Lupus Activity Measure (SLAM). Cutoff for antibody positivity was set at three standard deviations (SD) above the mean optical density obtained in sera from 34 healthy subjects. Positive sera were arbitrarily subdivided into low (from >3 to 5 SD), medium (from >5 to 10 SD), and high (>10 SD) positive. IgG, IgM, and IgA anti-LF were detected in 53, 18, and 14 patients, respectively. IgG1, IgG2, IgG3, and IgG4 anti-LF were demonstrated in 34, 10, 31, and 35 patients, respectively. IgG anti-LF at the medium/high level were found in 33 patients, correlated with disease activity (p = 0.017), anti-dsDNA (0.04), and anticardiolipin antibodies (p = 0.02) and were associated with Raynaud's phenomenon (p = 0.028), renal involvement (p = 0.007), serositis (p = 0.026), and history of thrombosis (p = 0.006). Anti-LF of IgM, IgA, or IgG subclass isotypes showed no correlation with clinical and serological findings. Our results demonstrate that anti-LF are frequently present in patients affected by SLE. IgG anti-LF at the medium/high level are associated with some clinical manifestations and other autoantibodies. However, it remains to be established whether anti-LF play a specific pathogenic role.

Expression of lactoferrin on neutrophil granulocytes from synovial fluid and peripheral blood of patients with rheumatoid arthritis.

OBJECTIVE: To analyze lactoferrin expression on synovial fluid (SF) and peripheral blood neutrophils of patients with rheumatoid arthritis (RA) and to compare it with the lactoferrin expression on neutrophils from patients with osteoarthritis (OA). METHODS: Paired samples of peripheral blood and SF were obtained from 14 patients with RA and 9 patients with OA. Lactoferrin expression was evaluated on cell surfaces by cytofluorimetric analysis utilizing both polyclonal antibodies and the monoclonal anti-lactoferrin antibody AGM 2.29. Data are presented as mean fluorescence intensity. RESULTS: In patients with RA, the expression of membrane lactoferrin was significantly increased on SF neutrophils in comparison with those in peripheral blood. This increase was found using both polyclonal antibodies and AGM 2.29 (p = 0.0001, p = 0.0017, respectively). In patients with OA, the difference was not significant. In addition, lactoferrin expression on SF neutrophils of patients with RA was significantly increased compared with that found on SF neutrophils of patients with OA (polyclonal antibodies, p = 0.0015; AGM 2.29, p = 0.005). In patients with RA, no correlation was found between lactoferrin expression and disease activity. CONCLUSION: Our results provide evidence for an activation of neutrophil granulocytes at site of inflammation in RA and indicate that lactoferrin surface expression represents a reliable neutrophil activation marker.

Antimicrobial and immunoregulatory functions of lactoferrin and its potential therapeutic application.

Lactoferrin is an iron-binding glycoprotein present in various secretions (eg. milk, tears, saliva,pancreatic juice, etc.). It is also stored in specific granules of polymorphonuclear granulocytes from which it is released following activation. Lactoferrin exerts a bactericidal activity by damaging the outermembrane of Gram-negative bacteria, as well as immunoregulatory functions by decreasing the release of interleukin-l (IL- 1), IL-2 and tumor necrosis factor-alpha INF-alpha) and enhancing monocyte and natural killer cell cytotoxicity. Lactoferrin binds with high affinity to lipid A, the toxic moiety of the lipopolysaccharide, or endotoxin from Gram-negative bacteria Lipopolysacchride interaction with monocytes/ma phages results in the production and release of TNF-alpha, that plays an important role in inducing septic shock In this respect, it has recently been demonstrated that lactoferrin inhibits the lipopolysaccharide interaction with CD14 on monocytes/macrophages by competition with the lipopolysaccharide binding protein. Therefore, besides its bactericidal activity, lactoferrin may also act by neutralizing the toxic effects of lipopolysaccharide and this protective role against endotoxin lethal shock has been demonstrated in animal models. Moreover, in vitro and in vivo neutralization of endotoxin by a human lactoferrin-derived peptide was also reported and lactoferrin or lactoferrin-derived peptides could represent useful tools for the treatment of endotoxin-induced septic hock. The recent production and characterization of monoclonal antibodies against different epitopes of human lactoferrin, including monoclonal antibodies selectively neutralizing lactoferrin binding to lipid A, may allow a better elucidation of the consequence of lactoferrin-lipopolysaccharide interaction.