Review Article

The Role of CD40/CD40 Ligand Interactions in Bone Marrow Granulopoiesis

Table 1

Pathogenetic and pathophysiologic features of X-linked Hyper IgM Syndrome and Chronic Idiopathic Neutropenia.

X-linked hyper-IgM syndromeChronic idiopathic neutropenia

Clinical featuresInfections, arthritis,mucosal ulcers, and neutropenia [7072]Neutropenia, and osteopenia/osteoporosis, usually uncomplicated course [75]
Immunologic Features/cytokinesElevated IgM, reduced IgG, IgA, and IgE levels [7072]Elevated TNFα, IFNγ, TGFβ, IL-1β, IL-6, and FasL [7577]
Pathophysiologic featuresMutations in the CD40L gene, abnormal T-cell mediated signals, failure of B-cell differentiation, and defective regulation of immunoglobulin isotype switching [7072]Impaired BM granulopoiesis and T-cell and cytokine-mediated suppression of hematopoiesis [7578]

Abbreviations: IgM, immunoglobulin-M; IgG, immunoglobulin-G; IgA, immunoglobulin-A; IgE, immunoglobulin-E; TNFα, tumour necrosis factor-α; TGFβ, transforming growth factor-β; IL-1β, inteleuκin-1β; IL-6, interleukin-6; BM, bone marrow.