Kidney Week

Abstract: TH-OR32

Associations Between the Immunoglobulin Germline Gene Usage and the Tropism of Organ Involvement and Renal Amyloid Deposition Patterns in Immunoglobulin Light-Chain Amyloidosis by Mass Spectrometry

Session Information

• Onco-Nephrology Updates in Practice
  October 22, 2020 | Location: Simulive
  Abstract Time: 05:00 PM - 07:00 PM

Category: Onco-Nephrology

• 1500 Onco-Nephrology

Authors

• Li, Dan Yang, Peking University First Hospital, Beijing, Beijing, China

Dan Yang Li, PhD



Dan-yang Li, Ph.D. candidate, Renal Division, Department of Medicine, Peking University First Hospital; Renal Pathological Center, Institute of Nephrology, Peking University; Key Laboratory of Renal Disease, Ministry of Health of China; Key Laboratory of CKD Prevention and Treatment, Ministry of Education of China; Beijing, People’s Republic of China

• Liu, Dan, Peking University Health Science Center School of Foundational Education, Beijing, Beijing, China

Dan Liu,

• Wang, Su-xia, Peking University First Hospital, Beijing, Beijing, China

Su-xia Wang,

• Zhao, Ming Hui, Peking University First Hospital, Beijing, Beijing, China

Ming Hui Zhao,

Background

The goal of this study was to characterize the associations between the immunoglobulin light chain variable region (IGVL) germline gene usage and organ tropism, renal amyloid deposition patterns in Chinese patients with AL amyloidosis.

Methods

105 patients were selected randomly from an overall database of 310 patients with AL amyloidosis diagnosed by renal biopsies during 2000 to 2018. The clinical manifestation and organ involvement were assessed. The renal amyloid deposits on different compartments were evaluated and classified into three patterns: (1) glomerular dominant amyloid deposition pattern (G-AL, n=27); (2) vascular dominant deposition pattern (V-AL, n=32); (3) diffuse amyloid deposition pattern (D-AL, n=46). IGVL germline gene usage was identified based on proteomic analysis of renal amyloidotic tissue by mass spectrometry using a reference database supplemented with sequences of IGVL of AL amyloidosis. The associations of IGVL genes with organ involvement, renal amyloid deposition patterns and survival were assessed.

Results

IGVL genes were successfully identified in 84.8% patients (89/105). LV 6-57 (31.2%) was the most common λ IGVL gene identified among patients with AL amyloidosis, and KV 1-33 (50.0%) was predominant in κ IGVL patients. When compared with patients with renal involvement, the frequency of LV 1-44 (12.1% vs 4.3%, P=0.639) and LV 1-47 (9.1% vs 4.3%, P=0.636) were high among patients with combined renal and cardiac involvement. Among the specific compartment of kidney with amyloid deposits, LV 6-57 was more likely to have G-AL (42.9% vs 26.9% vs 26.7%, P=0.399), and LV 1-51 was associated with V-AL (19.2% vs 3.3% vs 0, P=0.019). Patients with LV 2 family had a tendency at increased risk of developing into ESRD compared with other IGVL families (P=0.027).

Conclusion

IGVL germline gene usage was associated with organ tropism, renal amyloid deposition patterns and renal survival in Chinese patients with AL amyloidosis. Whereas, the results were preliminary and exploratory, and should be proved in a large cohort of AL amyloidosis patients.

Funding

• Government Support - Non-U.S.