We have identified a distinct pre-naive B cell population circulating in human peripheral blood that exhibits an intermediate phenotype between transitional and naive B cells. Like human transitional B cells, these cells express CD5 but have intermediate densities of CD38, CD10, CD9, and the ABCB1 transporter compared with transitional and naive B cells. These pre-naive B cells account for a ma...

OBJECTIVES To describe the clinicopathologic findings of seven patients with CD5-positive nodal marginal zone lymphoma (NMZL). METHODS We searched cases of NMZL over a 10-year interval and identified seven cases of CD5-positive NMZL. The clinical, histologic, and immunophenotypic findings of this group were reviewed, and the frequency of dissemination in this group was compared with that of 6...

Delayed maturation of the immune system has been proposed to be a risk factor for development of allergy, but B cell maturation in relation to allergic disease has not been examined. B cells lose CD5 and acquire CD27 during maturation from immature via mature/naive to Ig-secreting cells and memory cells. We sought to investigate B cell maturation in relation to development of allergic disease a...

CD5, a type I glycoprotein expressed by T cells and a subset of B cells, is thought to play a significant role in modulating Ag receptor signaling. Previously, our laboratory has shown that bovine B cells are induced to express this key regulatory molecule upon Ag receptor cross-linking. To date, a ligand has not been described for bovine CD5. Given the importance ligand binding presumably play...

BACKGROUND AND OBJECTIVES B cell significance in ANCA disease pathogenesis is underscored by the finding that ANCA alone can cause disease in mouse models and by the effectiveness of rituximab as therapy in ANCA-small vessel vasculitis (ANCA-SVV). To avoid infections and adverse events from therapy, clinicians require improved markers of disease activity and impending relapse to guide immunosup...

Regulating the differentiation and persistence of encephalitogenic T cells is critical for the development of experimental autoimmune encephalomyelitis (EAE). We reported recently that CD5 has an engagement-dependent prosurvival activity in T cells that played a direct role in the induction and progression EAE. We predicted that CD5 regulates T cell apoptosis/survival through the activation of ...

Recently, we reported elevated proportions of circulating follicular T helper cells and higher levels of interleukin- (IL-) 21 in primary Sjögren's syndrome (pSS). Interaction of invariant natural killer T (iNKT) cells with B cells and granzyme B (GrB) production may be also important in pSS. Thirty-two pSS patients and 24 healthy controls were enrolled in our study. We investigated the express...

Triggering of the T cell receptor initiates a signaling cascade resulting in the activation of the T cell. These signals are integrated alongside those resulting from the triggering of other receptors whose function is to modulate the overall response. CD5 is an immunotyrosine-based inhibition motif-bearing receptor that antagonizes the overt T cell receptor activation response by recruiting in...