Functional impact of A91V mutation of the PRF1 perforin gene.
Perforin (PRF1) gene mutations have been associated with Familial Hemophagocytic Lymphohistiocytosis type 2 (FHL2). Substitution p.A91V (c.272C>T) in exon 2 was first described as a neutral polymorphism. Nonetheless, recent clinical evidence and functional assays, suggest a potential pathogenic role for p.A91V, especially in compound heterozygous individuals. Moreover, p.A91V homozygosity has been linked to various pathological states including FHL and lymphocytic leukaemias. In the present report we evaluated the impact of this mutation in a compound heterozygous A91V/G149S 31 year-old asymptomatic female. Functional assays revealed low perforin expression levels, as well as an impaired NK cell-mediated cytotoxicity, partially reconstituted after incubation with IL-2. These results support that p.A91V mutation, associated to another mutated PRF1 allele, may potentially predispose seemingly healthy carriers to suffer a milder FHL2 clinical phenotype, including later onset of the disease. Thus, clinical monitoring of p.A91V carrier individuals bearing another mutation in PRF1 is warranted.
Department of Immunology, University Hospital of Son Espases, Palma de Mallorca, Spain. natalia.martinez@ssib.es
Natalia
N
Martínez-Pomar
Nallibe
N
Lanio
Neus
N
Romo
Miguel
M
Lopez-Botet
Núria
N
Matamoros
D000328:Adult; D058070:Asymptomatic Diseases; D001483:Base Sequence; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D005091:Exons; D005260:Female; D006579:Heterozygote; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology / Q000473:pathology; D051359:Lymphohistiocytosis, Hemophagocytic / Q000175:diagnosis / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D008969:Molecular Sequence Data; D009154:Mutation; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins / Q000235:genetics*
D007376:Interleukin-2; C510468:PRF1 protein, human; D052899:Pore Forming Cytotoxic Proteins; D054353:Perforin