The Functional Basis for Hemophagocytic Lymphohistiocytosis in a Patient with Co-inherited Missense Mutations in the Perforin (PFN1) Gene
نویسندگان
چکیده
About 30% of cases of the autosomal recessive immunodeficiency disorder hemophagocytic lymphohistiocytosis are believed to be caused by inactivating mutations of the perforin gene. We expressed perforin in rat basophil leukemia cells to define the basis of perforin dysfunction associated with two mutations, R225W and G429E, inherited by a compound heterozygote patient. Whereas RBL cells expressing wild-type perforin (67 kD) efficiently killed Jurkat target cells to which they were conjugated, the substitution to tryptophan at position 225 resulted in expression of a truncated ( approximately 45 kD) form of the protein, complete loss of cytotoxicity, and failure to traffic to rat basophil leukemia secretory granules. By contrast, G429E perforin was correctly processed, stored, and released, but the rat basophil leukemia cells possessed reduced cytotoxicity. The defective function of G429E perforin mapped downstream of exocytosis and was due to its reduced ability to bind lipid membranes in a calcium-dependent manner. This study elucidates the cellular basis for perforin dysfunctions in hemophagocytic lymphohistiocytosis and provides the means for studying structure-function relationships for lymphocyte perforin.
منابع مشابه
Perforin Gene Analaysis in an Iranian Family with Familial Hemophagocytic Lymphohistiocytosis
Perforin gene (PRF1) mutations have been reported in 20-30% of patients with familial hemophagocytic lymphohistiocytosis (FHL), an immune disorder of infancy and early childhood. Cytotoxic T and natural killer (NK) cell activities are remarkably reduced or ab-sent in FHL patients. We report the first cases of familial hemophagocytic lymphohistiocy-tosis in an Iranian family with two siblings. E...
متن کاملA functional analysis of the putative polymorphisms A91V and N252S and 22 missense perforin mutations associated with familial hemophagocytic lymphohistiocytosis.
Up to 60% of cases of the autosomal recessive immunodeficiency hemophagocytic lymphohistiocytosis (HLH) are associated with mutations in the perforin (PRF1) gene. In this study, we expressed wild-type and mutated perforin in rat basophil leukemia cells to study the effect on lytic function of the substitutions A91V and N252S (commonly considered to be neutral polymorphisms) and 22 perforin miss...
متن کاملA FUNCTIONAL ANALYSIS OF THE PUTATIVE POLYMORPHISMS A91V AND N252S, AND 22 MISSENSE PERFORIN MUTATIONS ASSOCIATED WITH FAMILIAL HEMOPHAGOCYTIC LYMPHOHISTIOCYTOSIS. Short Title: Analysis of perforin mutations associated with HLH
Up to 60% of cases of the autosomal recessive immunodeficiency, hemophagocytic lymphohistiocytosis (HLH) are associated with mutations in the perforin (PRF1) gene. In this study, we expressed wild-type and mutated perforin in rat basophil leukemia cells to study the effect on lytic function of the substitutions A91V and N252S (commonly considered to be neutral polymorphisms), and 22 perforin mi...
متن کاملBiology and Treatment of Hemophagocytic Lymphohistiocytosis
Hemophagocytic lymphohistocytosis (HLH) is a hyperinflammatory syndrome that occurs at all ages and is characterized by high levels of cytokines, secreted by activated T-lymphocytes and macrophages. All symptoms and laboratory changes can be explained by organ infiltration by these cells and hypercytokinemia. HLH occurs as an inherited form (genetic, primary HLH) with mutations primarily in the...
متن کاملAberrant maturation of mutant perforin underlies the clinical diversity of hemophagocytic lymphohistiocytosis.
Missense mutations in perforin, a critical effector of lymphocyte cytotoxicity, lead to a spectrum of diseases, from familial hemophagocytic lymphohistiocytosis to an increased risk of tumorigenesis. Understanding of the impact of mutations has been limited by an inability to express human perforin in vitro. We have shown, for the first time to our knowledge, that recombinant human perforin is ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of Experimental Medicine
دوره 200 شماره
صفحات -
تاریخ انتشار 2004