A higher frequency of CD4⁺CXCR5⁺ T follicular helper cells in adult patients with minimal change disease

B cell phenotype, activity, and function in idiopathic nephrotic syndrome

Idiopathic nephrotic syndrome (INS) is the most frequent glomerular disease in childhood. However, its underlying etiology mechanism lacks thorough understanding. Previous studies have described INS as a T cell functional disorder resulting in increased plasma lymphocyte-derived permeability factors. In children with frequent relapses of nephrotic syndrome, the mechanism underlying the therapeutic efficacy of CD20 monoclonal antibodies in depleting B cells may provide additional evidence in exploring the critical role of B lymphocytes in INS pathogenesis. Previous studies have proposed that RTX bound to CD20 through antibody-dependent and complement-dependent cytotoxicity and led to lytic clearance of B cells. Additionally, RTX exerted an effect by blocking the interaction between B and T cells or regulating homeostasis and functions of T cell subsets. Recent studies on the development, differentiation, and activation of B-lymphocytes in glomerular diseases have suggested that the B-lymphocytes participate in the INS pathogenesis through interaction with T cells, secretion of antibodies, or production of cytokines. In this study, we aimed to provide a detailed description of the current knowledge on the development, differentiation, activity, functions, and related regulating factors of B cells involved in INS. Thus, further understanding of the immunopathogenesis of INS may offer some opportunities in precisely targeting B cells during therapeutic interventions. IMPACT: The topic "B cells play a role in glomerular disease" is a novel point, which is not completely described previously. We described interactions between T and B cells and immunoglobulin, IgG, IgM, IgE, etc. as well in glomerular disease. The research of regulatory factors associated with B cell's function, like BAFF, is a hot topic in other diseases; however, it is rare in glomerular disease.

The Germinal Center Milieu in Rheumatoid Arthritis: The Immunological Drummer or Dancer?

Rheumatoid Arthritis (RA) is a chronic autoimmune disease characterized by joint inflammation, affecting approximately 1% of the general population. To alleviate symptoms and ameliorate joint damage, chronic use of immunosuppressives is needed. However, these treatments are only partially effective and may lead to unwanted side effects. Therefore, a more profound understanding of the pathophysiology might lead to more effective therapies, or better still, a cure. The presence of autoantibodies in RA indicates that B cells might have a pivotal role in the disease. This concept is further supported by the fact that a diverse antibody response to various arthritis-related epitopes is associated with arthritis development. In this context, attention has focused in recent years on the role of Germinal Centers (GCs) in RA. Since GCs act as the main anatomic location of somatic hypermutations, and, thus, contributing to the diversity and specificity of (auto) antibodies, it has been speculated that defects in germinal center reactions might be crucial in the initiation and maintenance of auto-immune events. In this paper, we discuss current evidence that various processes within GCs can result in the aberrant production of B cells that possess autoreactive properties and might result in the production of RA related autoantibodies. Secondly, we discuss various (pre-)clinical studies that have targeted various GC processes as novel therapies for RA treatment.

Monoclonal B lymphocytosis and minimal change disease: a new monoclonal B-cell disorder of renal significance?

Chronic lymphocytic leukemia (CLL) may induce renal complications, which are becoming increasingly common, but in this context the occurrence of minimal change disease (MCD) remains rare. Monoclonal B lymphocytosis (MBL) is a precursor state of CLL and is currently under recognized. Since MBL is seen as a benign disorder that rarely evolves into CLL, screening for MBL is not standardized and does not require any treatment. When reviewing renal disease associated with MBL, there is very scant data in the literature and to date there is no case describing the association between MBL and MCD. Here, we describe the case of a 71-year old woman admitted for nephrotic syndrome (NS). We diagnosed a MBL. Kidney biopsy revealed MCD. Treatment with corticosteroids was introduced but no improvement was observed. Chemotherapy with rituximab and chlorambucil was thus started, leading to complete remission of both MBL and MCD. To our knowledge, this is the first description of the association of MBL and MCD. This case suggests that screening for MBL may have unexpected diagnostic and therapeutic implications in patients presenting with seemingly idiopathic NS.

A Lower Proportion of Regulatory B Cells in Patients with Henoch-Schoenlein Purpura Nephritis

Background

Henoch—Schoenlein purpura is the one of most common types of systemic vasculitis that involves impaired renal function and Henoch-Schoenlein purpura nephritis (HSPN). The diagnosis of this condition is largely based on immunohistologic detection of immunoglobulin A1-containing immune complex in the glomerular deposits of mesangium. Despite clinical advances, the etiopathogenesis of HSPN is still largely unknown.

Methods

In this study, we enrolled 25 newly diagnosed HSPN patients and 14 healthy controls. Then, fractions of B cell subtypes were determined in venous blood using flow cytometry. The serum interleukin (IL)-10 concentration was determined by enzyme-linked immunosorbent assay.

Results

Compared to those in healthy controls, the numbers of CD38⁺CD19⁺, CD86⁺CD19⁺, CD38⁺CD86⁺CD19⁺, and CD95⁺CD19⁺ B cells per microliter of blood were significantly higher in HSPN patients. In contrast, the numbers of CD5⁺CD19⁺, IL-10⁺CD19⁺, CD5⁺CD1d⁺CD19⁺, and IL-10⁺CD5⁺CD1d⁺CD19⁺ B cells per microliter of blood and the serum IL-10 concentration were significantly lower in HSPN patients. Following treatment, the numbers of CD38⁺CD19⁺ and CD86⁺CD19⁺ B cells per microliter of blood were significantly reduced in HSPN patients. However, the numbers of CD5⁺CD1d⁺CD19⁺, CD5⁺CD1d⁺IL-10⁺CD19⁺, and IL-10⁺CD19⁺ B cells per microliter of blood and the serum IL-10 concentration were significantly increased in HSPN patients following treatment. The estimated glomerular filtration rate (eGFR) was negatively correlated with the number of CD38⁺CD19⁺ B cells but positively correlated with the numbers of IL-10⁺CD19⁺, CD1d⁺CD5⁺CD19⁺, and IL-10⁺CD1d⁺CD5⁺CD19⁺B cells per microliter of blood and the serum IL-10 concentration. The 24-h urinary protein concentration was positively correlated with the number of CD38⁺CD19⁺B cells but negatively correlated with the numbers of IL-10⁺CD19⁺, CD1d⁺CD5⁺CD19⁺, and IL-10⁺CD1d⁺CD5⁺CD19⁺B cells per microliter of blood and the serum IL-10 concentration.

Conclusion

Our results suggest that CD38⁺CD19⁺ and CD1d⁺CD5⁺CD19⁺ B cells (Bregs) contribute to the pathogenesis of HSPN.

Renal complications in chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis: the Mayo Clinic experience

While the renal complications of plasma cell dyscrasia have been well-described, most information in patients with chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis is derived from case reports. This is a retrospective analysis of patients with chronic lymphocytic leukemia or monoclonal B-cell lymphocytosis who underwent kidney biopsy for renal insufficiency and/or nephrotic syndrome. Between January 1995 and June 2014, 49 of 4,024 (1.2%) patients with chronic lymphocytic leukemia (n=44) or monoclonal B-cell lymphocytosis (n=5) had a renal biopsy: 34 (69%) for renal insufficiency and 15 (31%) for nephrotic syndrome. The most common findings on biopsy were: membranoproliferative glomerulonephritis (n=10, 20%), chronic lymphocytic leukemia interstitial infiltration as primary etiology (n=6, 12%), thrombotic microangiopathy (n=6, 12%), and minimal change disease (n=5, 10%). All five membranoproliferative glomerulonephritis patients treated with rituximab, cyclophosphamide and prednisone-based regimens had recovery of renal function compared to 0/3 patients treated with rituximab with or without steroids. Chronic lymphocytic leukemia infiltration as the primary cause of renal abnormalities was typically observed in relapsed/refractory patients (4/6). Thrombotic microangiopathy primarily occurred as a treatment-related toxicity of pentostatin (4/6 cases), and resolved with drug discontinuation. All cases of minimal change disease resolved with immunosuppressive agents only. Renal biopsy plays an important role in the management of patients with chronic lymphocytic leukemia or monoclonal B-cell lymphocytosis who develop renal failure and/or nephrotic syndrome.