In the chaotic realm of emergency medicine, where minutes can mean the difference between life and death, physicians face a relentless challenge: swiftly diagnosing infections and determining the best course of treatment. The complexity intensifies in critical cases such as sepsis, where the body’s immune response can veer dramatically from one patient to another. Now, groundbreaking research spearheaded by Dr. Purvesh Khatri, a professor of biomedical informatics, is illuminating a path toward precision medicine tailored to the immune system’s nuanced activity in these high-stakes scenarios.
This pioneering work hinges on the interpretation of gene expression patterns—referred to as immune cell gene signatures—as a diagnostic and prognostic compass. By decoding these genetic signatures gleaned from blood samples, doctors can distinguish between bacterial and viral infections and more critically, assess how severely a patient’s immune system has become dysregulated. The implications of this approach are profound: it empowers clinicians to tailor treatments with unprecedented accuracy, potentially enhancing outcomes while mitigating the risks of inappropriate interventions such as unnecessary antibiotic use.
Dr. Khatri’s recent contributions, published in two seminal papers in Nature Medicine, demonstrate robust validation of a suite of molecular tests ready for clinical deployment. Among these tools is the FDA-cleared TriVerity test, which evaluates the activity of 29 targeted genes within immune cells. Leveraging artificial intelligence algorithms, TriVerity computes probabilistic scores indicating the likelihood of bacterial infection, viral infection, and the severity of illness, including the anticipated need for intensive care within a week.
The clinical validation of TriVerity, encompassing over 1,200 patients from multiple emergency departments across the United States and Europe, showed exceptional performance. The test surpassed existing clinical standards in identifying infections accurately and predicting illness severity. Importantly, it also offered clearer guidance on antibiotic usage, potentially reducing the overuse of these agents and the consequent development of antibiotic resistance—a global health concern.
Building on these diagnostic capabilities, Khatri’s team ventured further into therapeutic guidance through the development of the Human Immune Dysregulation Evaluation Framework (HI-DEF). This innovative scoring system quantitatively distinguishes between “good” immune gene signatures indicative of balanced and healthy immune responses, and “bad” signatures revealing harmful dysregulation. By parsing immune responses into myeloid and lymphoid axes—two principal arms of the immune system—the HI-DEF framework stratifies patients into four groups reflecting different states of immune homeostasis or imbalance.
The granularity offered by HI-DEF affords a nuanced understanding of how immune dysfunction correlates with clinical outcomes across diverse critical illnesses, from sepsis to burn injuries and acute respiratory distress syndrome. This stratification enables clinicians to conceptualize cases not merely as infections needing broad treatment but as immune-driven disorders requiring precision immunomodulatory therapies. For example, patients exhibiting myeloid dysregulation may respond favorably to medications designed to modulate myeloid lineage activity, while those with lymphoid dysregulation might benefit from therapies targeting the lymphoid compartment.
Intriguingly, the studies reveal that steroid therapy, often a double-edged sword in critical care, could be selectively beneficial when immune dysregulation profiles are taken into account. Patients with high lymphoid dysregulation showed improved survival rates with steroids, whereas those with balanced immune signatures experienced worse outcomes under the same regimen. This insight underscores the critical need for immune profiling to tailor therapeutic decisions rather than relying on conventional, one-size-fits-all protocols.
The deployment of these gene signature analyses is envisioned as a rapid, bedside-compatible diagnostic and prognostic platform. Combining TriVerity and HI-DEF tests could yield results within approximately 30 minutes, providing emergency clinicians with actionable information during the narrow therapeutic window critical in acute illnesses. This integrated approach stands to revolutionize emergency care by swiftly delineating infection presence, predicting illness trajectory, and guiding individualized treatment strategies grounded in the patient’s unique immune response.
Beyond the ICU, Dr. Khatri envisions a broader utility for immune dysregulation scoring. Early immune system imbalances, detectable via blood gene signatures, might serve as harbingers of worsening health or chronic conditions. For instance, preliminary data link high “bad” gene signature counts to diseases like diabetes and potentially other metabolic or inflammatory disorders. With further validation, routine immune profiling could become a staple in annual health evaluations, offering a proactive window into immune health and disease susceptibility well before critical illness manifests.
The collaborative effort behind these advancements spans an impressive international network of research institutions and hospitals, reflecting a shared commitment to addressing the complexities of infectious and critical illnesses. This consortium has drawn on thousands of blood samples and patient datasets, integrating molecular biology, clinical care insights, and artificial intelligence to forge a comprehensive picture of immune function in health and disease.
While these advances are promising, the authors emphasize the necessity for prospective clinical trials to refine treatment algorithms and validate the utility of immune-guided therapies. Fine-tuning such precision approaches could unlock new paradigms in critical care, steering away from blanket treatments towards interventions calibrated on the patient’s molecular immune landscape. This shift harbors the potential not only to save lives but also to transform the economics and quality of emergency medicine globally.
As the medical community stands at the threshold of a new era, these developments highlight the profound impact of integrative biomedical informatics and genomics on real-world clinical challenges. Dr. Khatri’s vision of seamlessly integrating immune dysregulation assessment into routine emergency care and beyond reflects a future where personalized medicine transcends theory, becoming an indispensable tool that aligns therapeutic intent with immune realities.
In sum, decoding immune cell gene signatures opens an unprecedented window into the dynamism of critical illness, offering a blueprint for responsive, targeted interventions tailored to each patient’s immune state. This paradigm shift promises to reshape emergency and critical care, enabling clinicians to act not just quickly, but smartly, guided by the language of the immune system itself.
Subject of Research: Human tissue samples
Article Title: A consensus immune dysregulation framework for sepsis and critical illnesses
News Publication Date: 30-Sep-2025
Web References: Nature Medicine Paper on Treatment-focused Study, Nature Medicine Paper on Diagnostic Test Validation
References: DOI 10.1038/s41591-025-03956-5
Keywords: Sepsis, Emergency medicine
Tags: bacterial vs viral infection identificationDr. Purvesh Khatri research contributionsFDA-cleared diagnostic tests for infectionsgene expression patterns in infectionsimmune cell gene signaturesimmune system dysregulation assessmentimproving clinical outcomes through geneticsmolecular tests for immune responsepersonalized medicine in critical careprecision medicine in emergency medicinesepsis diagnosis and treatmenttailored treatment strategies for critically ill patients
