Serological and Molecular Characterization of Hepatitis C Virus-Related Cryoglobulinemic Vasculitis in Patients without Cryoprecipitate.

Prolonged B cells stimulation due to the Hepatitis C virus (HCV) can result in autoimmunity, stigmatized by rising levels of cryoglobulins (CGs), the rheumatoid factor (RF), and free light chains (FLC) of immunoglobulins (Ig) associated with a range of symptoms, from their absence to severe cryoglobulinemic vasculitis and lymphoma. Here, we aimed to identify an immunological signature for the earliest stages of vasculitis when cryoprecipitate is still not detectable. We firstly analyzed the IgG subclasses, FLC, and RF in 120 HCV-RNA-positive patients divided into four groups according to the type of cryoprecipitate and symptoms: 30 asymptomatic without cryoprecipitate (No Cryo), 30 with vasculitis symptoms but without CGs that we supposed were circulating but still not detectable (Circulating), 30 type II and 30 type III mixed cryoglobulinemia (Cryo II and Cryo III, respectively). Our results revealed that patients with supposed circulating CGs displayed a pattern of serological parameters that closely resembled Cryo II and Cryo III, with a stronger similarity to Cryo II. Accordingly, we analyzed the groups of Circulating and Cryo II for their immunoglobulin heavy chain (IgH) and T-cell receptor (TCR) gene rearrangements, finding a similar mixed distribution of monoclonal, oligoclonal, and polyclonal responses compared to a control group of ten HCV-RNA-negative patients recovered from infection, who displayed a 100% polyclonal response. Our results strengthened the hypothesis that circulating CGs are the origin of symptoms in HCV-RNA-positive patients without cryoprecipitate and demonstrated that an analysis of clonal IGH and TCR rearrangements is the best option for the early diagnosis of extrahepatic complications.

Cryoglobulinemic glomerulonephritis with underlying occult HBV infection and Waldenström macroglobulinemia: A case report.

INTRODUCTION: Occult hepatitis B virus (HBV) infection, defined as negative hepatitis B surface antigen (HBsAg) but detectable HBV DNA in serum and liver tissue, has very rarely been described in cryoglobulinemia (CG) patients. This case report sheds light on the possible link between occult HBV infection and CG. PATIENT CONCERNS: A 76-year-old man presented with rapidly deteriorating renal function within 1 year. DIAGNOSIS: Cryoglobulinemic glomerulonephritis was diagnosed through renal biopsy. Initially, the patient tested negative for HBsAg, but a low HBV viral load was later discovered, indicating an occult HBV infection. Further studies also revealed Waldenström macroglobulinemia (WM). INTERVENTIONS: We treated the patient as WM using plasma exchange and rituximab-based immunosuppressive therapy. OUTCOMES: After 1 cycle of immunosuppressive treatment, there was no improvement of renal function. Shortly after, treatment was discontinued due to an episode of life-threatening pneumonia. Hemodialysis was ultimately required. CONCLUSION: Future studies are needed to explore the link between occult HBV infection and CG, to investigate the mediating role of lymphomagenesis, and to examine the effectiveness of anti-HBV drugs in treating the group of CG patients with occult HBV infection. We encourage clinicians to incorporate HBV viral load testing into the evaluation panel for CG patients especially in HBV-endemic areas, and to test HBV viral load for essential CG patients in whom CG cannot be attributed to any primary disease.

Biomarkers in HCV-related mixed cryoglobulinemia patients withnon-Hodgkin lymphoma.

OBJECTIVE: Chronic Hepatitis C virus (HCV) infection can cause severe extrahepatic manifestations, such as mixed cryoglobulins (MC), up to the development of B cell nonHodgkin's lymphoma (B-NHL). Mechanisms transforming of HCV infection into lymphoproliferative and/or autoimmune disorders are still poorly understood. In course of HCV infection, the sustained virus-driven antigenic stimulation may probably induce a B-cell clonal expansion. Measurements of serum free light chains (FLCs) levels, considered as a direct marker of B cell activity, are analyzed with increasing interest in clinical practice, for diagnosis, monitoring and follow-up of plasma cell dyscrasia. Syndecan-1 (CD138) is a transmembrane heparan sulfate proteoglycan expressed and actively shed by most myeloma cells. Membrane CD138 represents the major receptor protein for HCV attachment to the hepatocyte surface and high levels of circulating sCD138 levels are detected in patients at early stage of B-cell chronic lymphocytic leukemia. This study is aimed to evaluate sCD138 and FLC levels as diagnostic biomarkers of HCV-related MC with B-NHL. PATIENTS AND METHODS: We enrolled 35 HCV-MC-NHL patients, characterized for the specific type of cryoglobulins, and 25 healthy blood donors (HBD) as negative control. Serum sCD138 levels were determined using ELISA kits specific for human sCD138. Serum FLCs were assessed by means of the turbidimetric assay. RESULTS: We found that serum levels of sCD138, as well as FLCs, were significantly higher in patients than in HBD (p<0.001). CONCLUSIONS: In agreement with the definition of HCV-driven lymphoproliferative disorders as the consequence of a multifactorial and multistep pathogenetic process, we suggest that sCD138 and FLCs could be considered putative independent markers of worsening progression of the disease.

Sentinel biomarkers in HCV positive patients with mixed cryoglobulinemia.

BACKGROUND: Infections, autoimmunity and cancer play a role as determinants of etiology in Hepatitis C virus (HCV) related mixed cryoglobulinemia (MC). Several factors of risk have been suggested as markers of pathogenesis and progression of HCV-related MC into B cell Non-Hodgkin's Lymphoma (B-NHL). Here, we evaluated IgG subclass distribution, free light chains (FLCs) and vascular endothelial growth factor (VEGF) as a new combination of biomarkers. METHODS: We measured IgG1-4 subclasses, FLCs and VEGF levels in sera 53 from HCV-related MC, in comparison with 40 sera from HCV negative patients with rheumatoid arthritis (RA) and 30 from healthy blood donors (HBD). RESULTS: IgG3 levels were significantly higher in HCV-MC patients with a decrement of IgG2 and IgG4; FLC levels significantly increased in both MC and RA patients' groups; serological VEGF was higher in HCV-MC patients than in HBD in correlation with k and λ levels. CONCLUSION: Our results suggest that a specific IgG subclasses pattern together with raised levels of FLCs and VEGF could represent the biomarker "signature" of an inflammation multistage of acquired immune system.

CD5/CD20 expression on circulating B cells in HCV-related chronic hepatitis and mixed cryoglobulinemia.

The role of CD5+ B cells in patients with HCV infection and HCV-related disorders, including mixed cryoglobulinemia (MC), has been addressed in previous reports with conflicting results. We established a correlation between CD5/CD20 expression on circulating B lymphocytes, characterizing monoclonal B cell lymphocytosis (MBL), and clinical features in a cohort of 45 patients with chronic HCV hepatitis [without MC: 23 patients (MC- group); with MC: 22 patients (MC+ group)], and 45 HCV-negative healthy subjects as controls. By flow cytometry analysis, three B cells phenotypes were singled out: 1) CD5+CD20dim (CLL-like phenotype); 2) CD5+CD20bright (atypical phenotype); and 3) CD5-CD20+ phenotype. CD5+CD20bright cells were reduced in MC- patients (p=0.049). CD5+CD20dim B cells were significantly higher in group B than in the control group (p=0.003). ROC curve analysis in MC+ patients showed the highest positive likelihood ratio at ≥7.35% (p=0.008) for CLL-like phenotype and at ≤63.6% (p=0.03) for the CD5-CD20+ B cell phenotype. HCV infection was associated with a higher frequency of CLL-like (odds ratio=16, p=0.002) and a lower frequency of atypical (odds ratio: 3.1, p=0.02) and CD5-CD20+ (odds ratio: 11, p=0.01) phenotypes. The association with higher levels of CLL-like phenotype progressively increased from group of MC- patients (odds ratio: 9.3, p=0.04) to the group of MC+ patients (odds ratio: 25.1, p=0.0003). CONCLUSIONS: The occurrence of a CLL-like pattern may allow to identify HCV-infected patients at risk of developing MC and eventually non-Hodgkin lymphoma, who should require a closer surveillance and a longer follow-up.

Hepatitis B virus-related cryogobulinemic vasculitis. The role of antiviral nucleot(s)ide analogues: a review.

Cryoglobulinemic vasculitis (CV) can develop in 1.2-4% of hepatitis B virus (HBV)-infected patients. HBV infection affects about 350 million people worldwide. It can progress from acute or fulminant hepatitis to chronic hepatitis, cirrhosis or hepatocellular carcinoma. Twenty per cent of HBV patients may develop extra-hepatic manifestations, such as polyarteritis nodosa, glomerulonephritis, dermatitis, polyarthralgias and arthritis, lung disease, aplastic anaemia. Our review focuses on the role of antiviral agent nucleot(s)ide analogues (NAs) in treatment of HBV-related CV. The studies in literature have demonstrated that NAs therapy in HBV-related CV yields high virological and satisfying clinical responses in most patients with mild-and-moderate CV, but a low response in severe CV. Overall, NAs represent a promising therapeutic option for HBV-related CV. Obtaining early suppression of HBV viral load should be the main virological and clinical goal in order to prevent organ complications and lymphoproliferative disorders.

Increased genomic instability following treatment with direct acting anti-hepatitis C virus drugs.

Mixed Cryoglobulinemic Vasculitis (MCV) is a prominent extra-hepatic manifestation of Hepatitis C virus (HCV) infection. HCV has been reported to cause B-cell disorders and genomic instability. Here, we investigated B-cell activation and genome stability in HCV-MCV patients receiving the direct antiviral agent, Sofosbuvir, at multiple centers in Egypt. Clinical manifestations in HCV-MCV patients were improved at the end of treatment (EOT), such as purpura (100%), articular manifestations (75%) and neuropathy (68%). Eighteen patients (56%) showed vasculitis relapse after EOT. BAFF and APRIL were higher at EOT and continued to increase one year following treatment onset. Chromosomal breaks were elevated at EOT compared to baseline levels and were sustained at 3 and 6 months post treatment. We report increased expression of DNA genome stability transcripts such as topoisomerase 1 and TDP1 in HCV-MCV patients after treatment, which continued to increase at 12 months from treatment onset. This data suggest that B-cell activation and DNA damage are important determinants of HCV-MCV treatment outcomes.

Interferon-free therapy in hepatitis C virus mixed cryoglobulinaemia: a prospective, controlled, clinical and quality of life analysis.

BACKGROUND: Cryoglobulinaemic vasculitis (CV) is a lymphoproliferative disorder related to hepatitis C virus (HCV) infection; anti-viral therapy is the first therapeutic option. CV can be incapacitating, compromising the patients' quality of life (QoL). In a controlled study, interferon-based therapy was associated with a lower virological response in vasculitic patients than in patients without vasculitis. Limited, uncontrolled data on direct-acting anti-virals are available. AIM: To evaluate safety, clinical efficacy, virological response and the impact of interferon-free treatment on QoL in HCV patients with and without mixed cryoglobulinaemia (MC). METHODS: We prospectively studied HCV patients with cryoglobulinaemia (with vasculitis-CV- and without vasculitis-MC-) and without cryoglobulinaemia (controls), treated with direct-acting anti-virals. Hepato-virological parameters, CV clinical response and impact on QoL were assessed. RESULTS: One hundred and eighty-two HCV patients were recruited (85 with CV, 54 with MC and 43 controls). A sustained virological response at 12 weeks (SVR12) was achieved in 166 (91.2%) patients (77/85 CV, 48/54 MC, 41/43 controls). In CV SVR patients, cryocrit levels progressively decreased and clinical response progressively improved, reaching 96.7%, 24 weeks after treatment. QoL, baseline physical and mental component summaries were lower in the CV group compared to the other groups (P < 0.05). Scores improved in all groups, and significantly in CV patients after SVR. CONCLUSIONS: No significant differences in SVR rates were recorded between cryoglobulinaemic patients and controls and a high clinical and immunological efficacy was confirmed in CV, supporting the role of interferon-free therapy as the first therapeutic option. Interestingly, CV patients had worse baseline QoL than other HCV-positive groups and interferon-free therapy was effective in significantly increasing QoL, suggesting the important role of direct-acting anti-viral-based therapy in improving CV's individual and social burden.

Treatment for hepatitis C virus-associated mixed cryoglobulinaemia.

BACKGROUND: Hepatitis C virus (HCV)-associated mixed cryoglobulinaemia is the manifestation of an inflammation of small and medium-sized vessels produced by a pathogenic IgM with rheumatoid factor activity generated by an expansion of B-cells. The immune complexes formed precipitate mainly in the skin, joints, kidneys or peripheral nerve fibres. Current therapeutic approaches are aimed at elimination of HCV infection, removal of cryoglobulins and also of the B-cell clonal expansions. The optimal treatment for it has not been established. OBJECTIVES: This review aims to look at the benefits and harms of the currently available treatment options to treat the HCV-associated mixed cryoglobulinaemia with active manifestations of vasculitis (cutaneous or glomerulonephritis). SEARCH METHODS: We searched the Cochrane Kidney and Transplant Specialised Register to 30 November 2017 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. SELECTION CRITERIA: All randomised controlled trials (RCTs) and quasi-RCTs looking at interventions directed at treatment of HCV-associated cryoglobulinaemic vasculitis (immunosuppressive medications and plasma exchange therapy) have been included. DATA COLLECTION AND ANALYSIS: Two authors independently assessed the retrieved titles and abstracts. Authors of included studies were contacted to obtain missing information. Statistical analyses were performed using random effects models and results expressed as risk ratio (RR) or mean difference (MD) with 95% confidence interval (CI). The planned primary outcomes were kidney disease, skin vasculitis, musculoskeletal symptoms, peripheral joint arthralgia, peripheral neuropathies, liver involvement, interstitial lung involvement, widespread vasculitis and death. Other planned outcomes were: therapy duration, laboratory findings, adverse effects, antiviral therapy failure, B-cell lymphoma, endocrine disorders and costs of treatment. MAIN RESULTS: Ten studies were included in the review (394 participants). None of them evaluated direct-acting antivirals. Seven studies were single-centre studies and three were multicentre. The duration of the studies varied from six to 36 months. The risk of bias was generally unclear or low. Three different interventions were examined: use of rituximab (3 studies, 118 participants); interferon (IFN) (IFN compared to other strategies (5 studies, 223 participants); six IFN months versus one year (1 study, 36 participants), and immunoadsorption apheresis versus only immunosuppressive therapy (1 study, 17 participants).The use of rituximab may slightly improve skin vasculitis (2 studies, 78 participants: RR 0.57, 95% CI 0.28 to 1.16; moderate certainty evidence) and made little of no difference to kidney disease (moderate certainty evidence). In terms of laboratory data, the effect of rituximab was uncertain for cryocrit (MD -2.01%, 95% CI -10.29% to 6.27%, low certainty evidence) and HCV replication. Rituximab may slightly increase infusion reactions compared to immunosuppressive medication (3 studies, 118 participants: RR 4.33, 95%CI 0.76 to 24.75, moderate certainty evidence) however discontinuations of the treatment due to adverse reactions were similar (3 studies, 118 participants: RR 0.97, 95% CI 0.22 to 4.36, moderate certainty evidence).Effects of lFN on clinical symptoms were evaluated only in narrative results. When laboratory parameters were assessed, IFN made little or no difference in levels of alanine transaminase (ALT) at six months (2 studies, 39 participants: MD -5.89 UI/L, 95%CI -55.77 to 43.99); rheumatoid factor activity at six months (1 study, 13 participants: MD 97.00 UI/mL, 95%CI -187.37 to 381.37), or C4 levels at 18 months (2 studies, 49 participants: MD -0.04 mg/dL, 95%CI -2.74 to 2.67). On the other hand, at 18 months IFN may probably decrease ALT (2 studies, 39 participants: MD -28.28 UI/L, 95%CI -48.03 to -8.54) and Ig M (-595.75 mg/dL, 95%CI -877.2 to -314.3), but all with low certainty evidence. One study reported infusion reactions may be higher in IFN group compared to immunosuppressive therapy (RR 27.82, 95%CI 1.72 to 449.18), and IFN may lead to higher discontinuations of the treatment due to adverse reactions (4 studies, 148 participants: RR 2.32, 95%CI 0.91 to 5.90) with low certainty evidence. Interferon therapy probably improved skin vasculitis (3 studies, 95 participants: RR 0.60, 95% CI 0.36 to 1.00) and proteinuria (2 studies, 49 participants: MD -1.98 g/24 h, 95% CI -2.89 to -1.07), without changing serum creatinine at 18 months (2 studies, 49 participants: MD -30.32 µmol/L, 95%CI -80.59 to 19.95).Six months versus one year treatment with IFN resulted in differences terms of the maintenance of the response, 89% of patients in the six months group presented a relapse and only 11% maintained a long-term response at one year, while in the one year group only 78% relapsed and long-term response was observed in 22%. The one-year therapy was linked to a higher number of side-effects (severe enough to cause the discontinuation of treatment in two cases) than the six-month schedule.One study reported immunoadsorption apheresis had uncertain effects on skin vasculitis (RR 0.44, 95% CI 0.05 to 4.02), peripheral neuropathies (RR 2.70, 95%CI 0.13 to 58.24), and peripheral joint arthralgia (RR 2.70, 95%CI 0.13 to 58.24), cryocrit (MD 0.01%, 95%CI -1.86 to 1.88) at six months, and no infusion reactions were reported. However when clinical scores were evaluated, they reported changes were more favourable in immunoadsorption apheresis with higher remission of severe clinical complications (80% versus 33%, P = 0.05) compared to immunosuppressive treatment alone.In terms of death, it was not possible to present a pooled intervention effect estimate because most of the studies reported no deaths, or did not report death as an outcome. AUTHORS' CONCLUSIONS: To treat HCV-associated mixed cryoglobulinaemia, it may be beneficial to eliminate HCV infection by using antiviral treatment and to stop the immune response by using rituximab. For skin vasculitis and for some laboratory findings, it may be appropriate to combine antiviral treatment with deletion of B-cell clonal expansions by using of rituximab. The applicability of evidence reviewed here is limited by the absence of any studies with direct-acting antivirals, which are urgently needed to guide therapy.

Long-term effects of the new direct antiviral agents (DAAs) therapy for HCV-related mixed cryoglobulinaemia without renal involvement: a multicentre open-label study.

OBJECTIVES: To investigate the long-term effects and safety of new direct anti-viral agents (DAAs) in patients with hepatitis C virus (HCV)-related mixed cryoglobulinaemia (MC) without renal involvement. METHODS: The study enrolled 22 consecutive patients, 19 received sofosbuvir-based regimen and three patients received other DAAs, individually tailored according to latest guidelines. As of December 2016, the median length of follow-up was 17 months (range 13-21). RESULTS: Extra-hepatic manifestations at enrollment were: purpura and arthralgia (12 cases), peripheral neuropathy (10 cases) and marginal zone B- lymphomas (2 cases). After a four-week DAA therapy, all patients became HCV- negative. Moreover, after 48 weeks since the beginning of DAA treatment, sustained regression of purpura and arthralgias was observed respectively in eight and in nine cases; peripheral neuropathy improved in seven cases, and cryocrit median values decreased from three (1-20) at baseline to two (1-12) after 48 weeks. Two cases with indolent marginal zone lymphomas did not show any haematological response: size and number of the involved nodes remained unchanged. In addition, the monoclonal B-cell population found in the peripheral blood in four cases did not disappear after recovery from HCV- RNA. Mild side effects occurred in nine patients, but six patients developed ribavirin-related anaemia requiring reduction of ribavirin dose. CONCLUSIONS: DAA therapy is safe and effective to eradicate HCV in MC, but seems associated with satisfactory clinical response in mild or moderate cryoglobulinaemic vasculitis and no response in B-NHL.

Hepatitis C Virus-Associated Extrahepatic Manifestations in Lung and Heart and Antiviral Therapy-Related Cardiopulmonary Toxicity.

Besides liver cirrhosis and hepatocellular carcinoma, chronic hepatitis C virus (HCV) infection is associated with many extrahepatic manifestations (EHMs). HCV exhibits lymphotropism that is responsible for various EHM. An important characteristic of HCV is escape from the immune system, which enables it to produce chronic infections and autoimmune disorders along with accumulation of circulating immune complexes. These EHMs have large spectrum, because they affect many organs such as heart, lungs, kidney, brain, thyroid, and skin. HCV-related cardiac and pulmonary manifestations include myocarditis, cardiomyopathies, cardiovascular diseases (i.e., Stroke, ischemic heart disease), chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, asthma, and interstitial lung diseases. This review discusses etiology and pathogenesis of HCV-associated cardiac and pulmonary manifestations and how different genes, immune system, indirectly linked factors (mixed cryoglobulinemia), liver cirrhosis, and antiviral treatment are involved in HCV-related heart and lung diseases, however, their exact mechanism is not clear.

Renal Manifestations of Hepatitis C Virus.

Hepatitis C virus (HCV) is a hepatotropic and lymphotropic virus responsible for hepatic and extrahepatic autoimmune and neoplastic disorders, including renal involvement, which is the consequence of immune-mediated organ damage due to glomerular deposition of immune-complex and/or anti-HCV IgG antibodies and complement. It can appear at any time during the natural history of HCV infection, more often as membranoproliferative glomerulonephritis, alone or in association with other HCV-related disorders. The presence of renal involvement should be investigated in HCV-infected individuals at the first referral and during clinical follow-up.

Treatment of Extrahepatic Manifestations of Hepatitis C Virus.

Chronic infection with hepatitis C virus (HCV) is a multifaceted disease characterized by many extrahepatic manifestations (EHMs) that affect outcome and quality of life. HCV eradication by antiviral treatment has been proved beneficial in preventing the development of EHMs and is also able to improve many HCV-related severe disorders and neurocognitive outcomes and quality of life. Until recently, antiviral therapy of EHMs was limited to the presence of interferon-based treatment, and was contraindicated in many patients because of hematologic toxicity or risk of exacerbating immune-mediated disorders. The availability of interferon-free regimens solves this issue allowing for enhanced safety and efficacy to provide universal treatment of HCV-related EHMs.

[Extrahepatic manifestations in chronic hepatitis C infected patients]. / Extrahepaticus manifesztációk idült hepatitis C-vírus-fertozöttekben.

The importance of chronic hepatitis C infection is significant. 3% of the World's population is infected. There is at least one extrahepatic manifestation in 50% of HCV patients, which makes the prognosis and mortality worse. The pathomechanisms included are cryoglobulin production, immunmechanisms, and direct viral effects. The authors summarize the main extrahepatic manifestations, as well as treatment possibilities. The aim is to draw attention to this colourful infection in order to improve the recognition in the era of the new effective direct antiviral agents. Orv. Hetil., 2017, 158(16), 603-612.

Direct-acting antiviral agents in the therapy of hepatitis C virus-related mixed cryoglobulinaemia: a single-centre experience.

BACKGROUND: The efficacy and safety of direct-acting antiviral agents (DAAs) were evaluated in a cohort of prospectively enrolled patients with hepatitis C virus (HCV)-related mixed cryoglobulinaemia (MC), an immune complex-mediated vasculitis of small and medium vessels in which the pathogenetic role of HCV has been clearly established. METHODS: Twenty-two patients received DAAs. Clinical and laboratory features were recorded at baseline, every 4 weeks until the end of treatment (EoT), and 12 weeks afterwards. Primary efficacy endpoints were (a) sustained virological response 12 weeks after therapy completion (SVR12), (b) regression of symptomatology (clinical response) and (c) cryoglobulin disappearance or cryocrit reduction ≥50% (immunological response). Complete response (CR) was defined as the occurrence of all three primary endpoints; partial response (PR) was defined as the occurrence of SVR12, with or without either immunological or clinical response; and no response was defined as missing the achievement of all three endpoints. RESULTS: All patients reached SVR12. Compared with basal values, mean cryocrit values were significantly decreased at EoT and SVR12. A significant reduction of alanine transaminase and a parallel increase of complement component C4 levels were also detected. Rheumatoid factor activity was significantly reduced at EoT but not at SVR12. At SVR12, a CR was established in 14 patients (63.7%) and a PR in 8 patients (36.3%). In one patient with small lymphocytic lymphoma, the tumour progressed despite viral clearance. Mild adverse events were recorded in nine patients (40.9%). CONCLUSIONS: The response rates induced by the use of DAAs in patients with MC were remarkably higher than those previously achieved with pegylated interferon-α/ribavirin, with or without rituximab. A much longer follow-up is desirable to achieve useful information in terms of persistent viral clearance and clinical response.

Direct-Acting Antiviral Therapy Restores Immune Tolerance to Patients With Hepatitis C Virus-Induced Cryoglobulinemia Vasculitis.

BACKGROUND & AIMS: Interferon-free direct-acting antiviral (DAA) therapies are effective in patients with hepatitis C virus-induced cryoglobulinemia vasculitis (HCV-CV). We analyzed blood samples from patients with HCV-CV before and after DAA therapy to determine mechanisms of these drugs and their effects on cellular immunity. METHODS: We performed a prospective study of 27 consecutive patients with HCV-CV (median age, 59 y) treated with DAA therapy (21 patients received sofosbuvir plus ribavirin for 24 weeks, 4 patients received sofosbuvir plus daclatasvir for 12 weeks, and 2 patients received sofosbuvir plus simeprevir for 12 weeks) in Paris, France. Blood samples were collected from these patients before and after DAA therapy, and also from 12 healthy donors and 12 individuals with HCV infection without CV. HCV load, cryoglobulins, and cytokines were quantified by flow cytometry, cytokine multiplex assays, and enzyme-linked immunosorbent assay. RESULTS: Twenty-four patients (88.9%) had a complete clinical response of CV to DAA therapy at week 24, defined by improvement of all the affected organs and the absence of relapse. Compared with healthy donors and patients with HCV infection without CV, patients with HCV-CV, before DAA therapy, had a lower percentage of CD4+CD25hiFoxP3+ regulatory T cells (P < .01), but higher proportions of IgM+CD21-/low memory B cells (P < .05), CD4+IFNγ+ cells (P < .01), CD4+IL17A+ cells (P < .01), and CD4+CXCR5+interleukin 21+ follicular T-helper (Tfh) cells (P < .01). In patients with HCV-CV, there was a negative correlation between numbers of IgM+CD21-/low memory B cells and T-regulatory cells (P = .03), and positive correlations with numbers of Tfh cells (P = .03) and serum levels of cryoglobulin (P = .01). DAA therapy increased patients' numbers of T-regulatory cells (1.5% ± 0.18% before therapy vs 2.1% ± 0.18% after therapy), decreased percentages of IgM+CD21-/low memory B cells (35.7% ± 6.1% before therapy vs 14.9% ± 3.8% after therapy), and decreased numbers of Tfh cells (12% ± 1.3% before therapy vs 8% ± 0.9% after therapy). Expression levels of B lymphocyte stimulator receptor 3 and programmed cell death 1 on B cells increased in patients with HCV-CV after DAA-based therapy (mean fluorescence units, 37 ± 2.4 before therapy vs 47 ± 2.6 after therapy, P < .01; and 29 ± 7.3 before therapy vs 48 ± 9.3 after therapy, P < .05, respectively). CONCLUSIONS: In a prospective clinical trial of patients with HCV-CV, DAA-based therapy restored disturbances in peripheral B- and T-cell homeostasis.