Preprint from Northwestern University Highlights Complementary Proteomic Analysis of Interleukin-6 Using Next-Generation Protein Sequencing™ and Mass Spectrometry

Quantum-Si Incorporated (NASDAQ:QSI) ("Quantum-Si," "QSI" or the "Company"), The Protein Sequencing Company™, announces a newly released preprint from researchers at Northwestern University, titled "Next-Generation Protein Sequencing and individual ion mass spectrometry enable complementary analysis of interleukin-6." The publication demonstrates the power of combining two cutting-edge technologies, Quantum-Si's Next-Generation Protein Sequencing™ (NGPS™) on Platinum®, and Individual Ion Mass Spectrometry (I2MS), to achieve a detailed analysis of key regions of the cytokine interleukin-6 (IL-6).

IL-6 is a key immune regulator and therapeutic target; however, its proteoform diversity can present significant analytical challenges. This study demonstrates how NGPS and I2MS provide complementary insights into the amino acid sequence, post-translational modifications, and proteoform variation of IL-6, paving the way for deeper understanding and potential therapeutic innovation.

"This preprint highlights the potential of merging Next-Generation Protein Sequencing with individual ion mass spectrometry," said Neil Kelleher, Ph.D., Professor at Northwestern University and senior author of the study. "By combining these methods, we can capture a fuller picture of IL-6 proteoforms, which is critical for advancing therapeutic innovation."

Key Findings:

• NGPS provided single amino acid resolution for IL-6 peptide fragments critical to receptor binding and function, resolving regions with low sequence coverage by mass spectrometry.
• I2MS enabled intact proteoform detection and localized modifications, including glycosylation, within regions involved in IL-6 signaling.
• Together these technologies provide high sequence coverage of overlapping and distinct regions of IL-6, offering a more comprehensive view of its structural and functional diversity.

"This study underscores the immense challenge of characterizing proteoforms, which has long been a barrier to developing novel therapies," said Jeff Hawkins, President and Chief Executive Officer of Quantum-Si. "By integrating Next-Generation Protein Sequencing into one of the world's leading proteomics labs, we're enabling new insights into IL-6, to advance therapeutic research. These findings highlight the transformative potential of combining NGPS with traditional methods to explore proteoforms with single amino acid precision in complex diseases like cancer and autoimmune disorders."

To read the preprint visit: Next-Generation Protein Sequencing and individual ion mass spectrometry enable complementary analysis of interleukin-6 | Quantum-Si

About Quantum-Si Incorporated

Quantum-Si, The Protein Sequencing Company™, is focused on revolutionizing the growing field of proteomics. The Company's Platinum® line of instruments enables Next-Gen Protein Sequencing™ that advances proteomic research, drug discovery, and diagnostics beyond what has been possible with existing proteomic tools. Learn more at quantum-si.com or follow us on LinkedIn or X.

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