Analysis of Serum IgG1 to Predict Progression and Therapeutic Effect in Patients with Multiple Myeloma

OBJECTIVE: The correlation between laboratory indicators and clinical treatment effects and the prognosis of multiple myeloma remains poorly understood. Therefore, our study investigated whether serum IgG subclasses could be employed as potential indicators contributed to evaluate the therapeutic effect and prognosis of patients with multiple myeloma. Patients and Methods. Records of patients with multiple myeloma were initially diagnosed at the First Affiliated Hospital of Soochow University, China, from August 1, 2017, to February 28, 2020. The assessment abilities of serological indicators for therapeutic effect were evaluated in patients compared with healthy controls. RESULTS: In 560 study patients with multiple myeloma, serum IgA, IgG, IgM, κ-LC, and λ-LC increased by15%, 33.04%, 1.96%, 27.50%, and 26.43%, respectively. Further analysis found that IgG1, IgG2, IgG3, and IgG4 were over the upper limit of the reference range with 26.38%, 6.09%, 8.12%, and 4.64%, respectively. κ-LC and λ-LC were found in the urine in 65.13% and 29.70%, respectively. In peripheral blood, the proportion of CD3(+)CD4(+), CD3(−)CD19(+) cells, and CD4(+)/CD8(+) decreased, whereas CD3(+)CD8(+) cells and CD16(+)/CD56(+) increased, and the associated cytokines IL-2, IL-4, IL-6, TNF-α, and IFN-γ were upregulated in patients when compared with healthy controls. Furthermore, the serum levels of IgA, IgG, IgG1, IgG2, IgG3, and IgG4 gradually decreased in patients before, during, and after treatment. Similar results were found in serum and urine κ-LC and λ-LC. CONCLUSION: Serum IgG1 level could serve as the potential indicator for evaluating the therapeutic effect for patients with multiple myeloma. κ-LC and λ-LC also have the potential to be prognostic indicators. More studies are warranted to explore these serological indicators for personalized therapy in the future.