IGHV gene rearrangements and stereotyped receptors in chronic lymphocytic leukemia from a South American multicenter study

DAVI TORRES; MARÍA ELENA MÁRQUEZ; RICARDO BIGNI; CAIO PEREZ GOMES; MIHOKO YAMAMOTO; PIERRE-ANTOINE DEGLESNE; ANDREA KRZYWINSKI; LORENA ZANELLA; MARÍA CABREJO; PABLO OPPEZZO; CARMEN STANGANELLI; NATALIA SOTELO; MARIA TERESA MUNIZ; ADRIANO SABINO; CELSO RODRÍGUEZ DA SILVA; JUANA CABRERA; CAMILA GALVANO; CECILIA LANG; HORACIO FERNÁNDEZ GRECO; GUILLERMO DIGHIERO; IRMA SLAVUTSKY; CLAUDIA ORTEGA; PRISCILLA SEGGES; PAULO CAMPREGHER; MARÍA L FERRARI DE CHAUFFAILLE; ELIANA ABDELHAY; JOSÉ LUIS LÓPEZ; RAIMUNDO BEZARES; EVANGELINA AGRIELLO; RAÚL GABÚS; ROCÍO HASSAN

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Workshop; International Workshop on Chronic Lymphocytic Leukemia (iwCLL); 2019

International Workshop on Chronic lymphocytic leukemia

The IGHV (immunoglobulin heavy-chain variable region) gene mutational status is an important prognostic factor in chronic lymphocytic leukemia (CLL). About 30% of CLL patients display highly similar B-cell receptor (BCR) sequences in the heavy chain complementarity determining region 3 (VH CDR3) and identical light chains, fulfilling the criteria of BCR immunoglobulin stereotypy. At present, there is limited information about IGHV repertoire and stereotyped BCRs in CLL patients from South America. In the current study, we have evaluated the IGHV mutational status, gene usage and stereotyped BCRs in CLL patients from four South American countries, in a multi-institutional collaboration study developed in the context of the Latin American Group of CLL (LAG-CLL). Our cohort included 900 unselected CLL patients from Argentina (362), Brazil (358), Uruguay (101) and Venezuela (79) (530 males and 370 females; mean age: 65.6 years, range: 27-105 years; Rai stages: 0: 38%, I-II: 43%, III-IV: 19%). PCR was performed on cDNA or gDNA using VH framework region 1 consensus family specific (VH1-VH6) or leader primers and antisense primers JH or Cμ. IgBLAST (http://www.ncbi.nlm.nih.gov/igblast) and the ImMunoGeneTics database (IMGT) (http://imgt.cines.fr) were used for analysis. IGHV sequences with