Abstract：Blood serves not only as a reflection of the body’s overall health but also as a key indicator of imbalances in the body’s internal ecosystem, which can contribute to the onset of many major diseases. The blood ecosystem encompasses the complex interactions among various blood cells, non-cellular components, and the interactions between blood and other tissues and organs throughout the body. The traditional approach—focused on localized, singular, and segmented interventions targeting pathological cells, tissues, or organs—has been the standard for decades. However, this strategy has become a limiting factor in advancing our understanding and treatment of chronic diseases. The rapid emergence of mass spectrometry-based proteomics and other advanced omics technologies now offers a crucial opportunity for a more comprehensive and systematic analysis of the blood ecosystem. By leveraging these new multidimensional omics technologies, we have conducted a digital analysis of the blood ecosystem in patients with systemic infections. This research paradigm opens new avenues for identifying precise diagnostic markers and therapeutic targets in cancer and other systemic diseases.