Decline of cellular activation in non-B cells after rituximab treatment in hepatitis C-associated mixed cryoglobulinemia vasculitis

Therapeutic Potential of Rituximab in Managing Hepatitis C-Associated Cryoglobulinemic Vasculitis: A Systematic Review

(1) Background. Hepatitis C infection often leads to extrahepatic manifestations, including cryoglobulinemic vasculitis. This systematic review aimed to assess the efficacy and safety of rituximab in treating hepatitis C-associated cryoglobulinemic vasculitis. (2) Methods. Following PRISMA guidelines, databases were searched for relevant studies. Eligibility criteria included studies on hepatitis C-associated cryoglobulinemic vasculitis treated with rituximab. (3) Results. Nine studies met the eligibility criteria and were included in this analysis. Rituximab was commonly administered at 375 mg/m2 weekly for one month. The results consistently demonstrated the efficacy of rituximab, whether as a standalone treatment or as part of a therapeutic regimen. The combination of rituximab with Peg-IFN-α and ribavirin significantly increased the complete response rate compared to Peg-IFN-α and ribavirin alone (54.5% vs. 33.3%, p < 0.05). The 3-year sustained response rate was notably higher in the rituximab combination group (83.3% vs. 40%). In another trial, rituximab achieved remission in 83.3% of patients at 6 months, compared to only 8.3% in the control group. The efficacy of rituximab was supported by long-term experience, with clinical benefits in patients with severe cryoglobulinemic vasculitis, including those resistant to standard therapies. Mild adverse events were generally reported, with rare severe reactions in some studies. (4) Conclusions: In conclusion, rituximab appeared to be effective and safe in managing hepatitis C-associated cryoglobulinemic vasculitis, either alone or with antiviral therapy.

Recent updates in the diagnosis and management of cryoglobulinemic vasculitis

INTRODUCTION

Cryoglobulinemic vasculitis (CV), also known as mixed cryoglobulinemic syndrome (MCS), is a systemic vasculitis that affects small blood vessels. It exhibits a wide range of clinical manifestations, making its treatment a continuing challenge for physicians.

AREAS COVERED

We conducted a comprehensive review to evaluate the current status of diagnosis, management, and treatment of mixed cryoglobulinemia (MC). The accurate clinical and serological evaluation plays a vital role in diagnosing MC, identifying potential comorbidities, and monitoring its main manifestations and complications. Treatment strategies should be individualized based on the underlying etiopathogenesis, the severity of organ involvement, and the associated underlying disease. At present, the two mainstays of CV treatment are direct antiviral agents (for HCV-related CV) and B-cell-targeted therapy.

EXPERT OPINION

MC remains one of the few autoimmune diseases where the etiology is known, at least for the majority of patients. Its pathogenetic mechanism offers a unique opportunity to investigate the interplay between infections and the immune system. Moving forward, the primary challenge will continue to lie in the treatment of resistant or refractory cases of CV, particularly those associated with autoimmune diseases, or cases classified as 'essential' CV.

Recovery of hepatitis C specific T-cell responses after rituximab therapy in hepatitis C mixed cryoglobulinemic vasculitis

Mixed cryoglobulinemic vasculitis is associated with monoclonal B cell expansion in patients with chronic hepatitis C (HCV) infection. B cell depletion therapy using rituximab, a CD20 monoclonal antibody, has been successful in achieving remission from symptomatic disease. This study investigated whether B cell depletion therapy has an impact on activation of HCV-specific T cell phenotype and function. Nineteen patients with Hepatitis C mixed cryoglobulinemic vasculitis were treated with 4 cycles of rituximab (375 mg/m² ) and variables were measured 6 months after therapy. Using flow cytometry and Enzyme-Linked Immunospot assay, the number of activated and tissue-like B cells and number of T cells expressing Programmed cell death protein 1 (PD-1), T-cell immunoglobulin and mucin-domain containing-3 (TIM-3), and multiple cytokines were measured before and after rituximab therapy. B cell depletion therapy is associated with a significant (P < 0.0001) decline in peripheral T cells with exhaustive phenotype, from pre-therapy to post-therapy-of rituximab (mean ± standard error): CD4+ (16.9 ± 0.9% to 8.9 ± 1.0%) and CD8+ (6.8 ± 0.6% to 3.0 ± 0.5%) T cells expressing PD-1 and CD4+ (11.0 ± 1.0% to 6.1 ± 0.8%) and CD8+ (12.7 ± 0.7% to 6.4 ± 0.4%) T cells expressing TIM-3. In addition, there was a significantly higher percentage of peripheral CD8+ T cells responding to HCV peptide stimulation in vitro secreting IFN-γ (4.55 ± 0.3 to 9.6 ± 1.0 IFN-γ/10⁶ PBMCs, P < 0.0001), and more than one cytokine (1.3 ± 0.1% to 3.8 ± 0.2%, P < 0.0001) after therapy compared to pre-therapy. B cell depletion therapy results in recovery of T cell exhaustion and function in patients with HCV cryoglobulinemic vasculitis.