[The clonal origin of the myeloma cells secreting three kinds of immunoglobulin from a multiple myeloma patient]

Abstract

Objective: To explore the clonal origin of myeloma cells from a multiple myeloma (MM) patient with 3 kinds of immunoglobulin (Ig).

Methods: Six primers for IgH variable region gene families VH1-VH6 and one primer of common join region (J) were used to perform reverse transcriptase polymerase chain reaction(RT-PCR). Five oligonucleotides of constant region gene (C mu, C delta, C gamma, C alpha and C epsilon) were also used as reverse primers. Different combination of primers were used to perform PCR. PCR products of IgH gene rearrangement were cloned and sequenced.

Results: A sharp and dense gene band appeared by using Ig VH3 gene family primer and J primer. The specific IgH gene bands also appeared by using primers of VH3 with C mu and C gamma and C alpha but not by primers of VH1, VH2, VH4, VH5 with J as well as VH3 with C delta and C epsilon. It indicated that there were IgM, IgG and IgA gene rearrangement. These gene products were cloned and sequenced. All 3 IgM, IgG and IgA gene sequences are identical.

Conclusion: Despite the oligoclonality of MM cell, the sequencing results of 3 IgH genes showed that all the malignant cells were monoclonal origin.