X-linked agammaglobulinemia (XLA) is a heritable immunodeficiency disorder that is caused by a differentiation block leading to almost complete absence of B lymphocytes and plasma cells. The affected protein is a cytoplasmic protein tyrosine kinase, Bruton's agammaglobulinemia tyrosine kinase (Btk). Btk along with Tec, Itk and Bmx belong to a distinct family of protein kinases. These proteins c...

Defects in Bruton's tyrosine kinase (Btk) are responsible for X chromosome-linked agammaglobulinemia in patients. Mutations in each of the structural domains of Btk have been detected in patients, yet a mechanistic explanation for most of these mutant phenotypes is lacking. To understand the possible role of the unique pleckstrin homology and Tec homology (PHTH) module of Btk, we have compared ...

We used a modified colony survival assay to measure the sensitivity to ionizing radiation of more than 50 lymphoblastoid cell lines from normal individuals and from patients with ataxia-telangiectasia, Nijmegen breakage syndrome variants, and X-linked agammaglobulinemia. All of these disorders are associated with an increased frequency of cancer. Lymphoblastoid cell lines from patients with ata...

conclusions according to the results of these work-ups, xla was diagnosed for the cases. introduction x-linked agammaglobulinemia (xla) is one of the primary humoral immunodeficiencies. it usually presents symptoms of recurrent infections, but in some unusual cases it may present rheumatologic manifestations. case presentation the current paper presents the cases of two boys with arthritis trea...

As a new disease entity is studied it becomes apparent that certain clinical and laboratory features are particularly helpful to the clinician in the recognition of the disorder. A consideration of the recent literature indicates that recurrent pulmonary disease has assumed this role in the disease syndrome associated with agammaglobulinemia. Recurrent pulmonary infections including bronchitis,...