EXPRESSION OF IMMUNOGLOBULIN SEQUENCES HOMOLOGOUS TO ANTI-SARS-CoV-2 ANTIBODIES AND HIV IN CHRONIC LYMPHOCYTIC LEUKEMIA CASES.

Abstract

Identification of epitopes recognized by leukemic B cells could provide insights into themolecular mechanisms of B cell transformation in chronic lymphocytic leukemia (CLL). Theaim of this paper was to compare nucleotide sequences of immunoglobulin heavy chain variable region (IGHV) genes in CLL with known sequences directed against antigens of different origins available in public databases. Analysis was performed in thegroups of 412unselected CLL patients with productive IGHV gene using polymerase chain reaction followed by direct sequencing. Homology between CLL Ig sequences and antibodies directed against autoantigens was found in 12patients (2.9%), homology between CLL Ig sequences and antiviral antibodies- in 35patients (8.5%). Most of these sequences belonged to stereotypical clusters. Among thesequences that have homology to antiviral antibodies, themost prevalent were cases homologous with antibodies against HIV (14cases, 3.4%) and SARS-CoV-2antigens (10cases, 2.4%). None of thepatients in our cohort was HIV-infected and thestudy was conducted before theemergence of SARS-CoV-2virus. Suggestions could be made about thepossible impact of past infection of SARS-CoV-2virus on thepathogenesis of CLL. In particular, an increase in theproportion of CLL cases with theexpression of some stereotyped BCR and/or an increase of CLL risk in thelong-term period after SARS-CoV-2virus infection is not excluded. This assumption needs to be verified by epidemiological data.