Review & editing

The gap

Evidence profile

Sourced from the future work and limitations of the source papers, classified as general, spanning 4 journals.

Supporting evidence — 4 representative gaps

• Current understanding of the NLRC4 Inflammasome in autoinflammation and enterocolitis (2026) · Communications Biology · doi

  (cid:129) Multi-omics profiling of intestinal and immune compartments to identify molecular pathways linking NLRC4 activation to tissue injury. (cid:129) Longitudinal cytokine and metabolomic analyses in patients to distinguish primary pathogenic drivers from secondary inflammatory responses. (cid:129) Development of refined conditional mouse models targeting epithelial and myeloid compartments to define cell type–specific contributions to disease. threatening NLRC4-MAS, inflammation and sustained disease control40,41,45. leading to rapid stabilization of systemic IL-1 blockade has also been widely employed, often as first-line ther- apy; however, therapeutic responses are frequently incomplete in IL- 18–dominant disease, underscoring cytokine-specific differences in patho- genic contribution and therapeutic sensitivity45. In addition, inhibition of mTOR signaling with rapamycin has shown benefit as an adjunctive strategy by reducing caspase-1 activation and downstream inflammasome- mediated cytokine secretion in patient-derived immune cells46. Tumor necrosis factor (TNF) blockade has been used empirically in a subset of patients, particularly those with severe intestinal inflammation, although clinical responses have been variable and the mechanistic justification remains indirect45,47,48. Interferon-γ (IFN-γ) blockade49 and fecal microbiota transplantation50 have also shown therapeutic benefit in select AIFEC cases, further highlighting the complex and multifactorial nature of disease pathogenesis. Despite the promise of these clinical interventions, interpretation of therapeutic efficacy is constrained by significant limitations. NLRC4- associated autoinflammatory diseases are extremely rare, and most pub- lished clinical experiences are derived from isolated case reports or very small case series. In addition, many reported patients had received multiple immunomodulatory treatments and were frequently treated with multiple agents concurrently, making it difficult to attribute clinical outcomes to a single intervention. Leveraging our newly developed NLRC4 V341A knock- in mouse model, we validated the therapeutic efficacy of both IL-18 and TNF-α blockade in AIFEC40. Notably, this model also revealed that affected pups develop severe systemic inflammation accompanied by profound hypoglycemia. Glucose supplementation significantly attenuated disease severity and improved survival, suggesting that metabolic stress may con- tribute to disease progression in NLRC4-driven autoinflammation. Immunometabolism plays a critical role in regulating immune cell function and tissue homeostasis, and glucose serves as a key energy source during immune activation under conditions of hyperinflammation. Both hyper- glycemia and hypoglycemia have been shown to influence inflammatory responses51–53. Although the precise mechanisms underlying the beneficial effects of glucose supplementation in the AIFEC model remain unclear, several potential pathways have been proposed, including: (1) restoration of immune metabolic balance, (2) reinforcement of epithelial barrier integrity, and (3) promotion of a beneficial microbial environment40. These findings suggest that metabolic dysregulation may contribute to NLRC4-driven pathology. Future studies will be needed to further investigate how hypo- glycemia contributes to autoinflammation and how NLRC4 hyperactivation leads to systemic metabolic alterations.

  generalfuture work
  Keywords: nlrc disease ammation immune therapeutic responses blockade bene clinical metabolic activation cytokine patients ammatory systemic
• Macrophage spatiotemporal plasticity in pulmonary diseases: decoding the niche at single-cell resolution (2026) · Frontiers in Immunology · doi

  review & editing. XZ: Funding acquisition, Resources, Supervision, Writing – review & editing. Understanding the spatiotemporal plasticity of pulmonary macrophages is reshaping therapeutic concepts in lung disease. Broad macrophage depletion strategies, such as systemic CSF1R inhibition, may affect protective macrophage populations involved in host defense, tissue repair, and immune surveillance (113). Single-cell and spatial multi-omics therefore support a more selec- tive framework focused on disease-associated macrophage states, niche-specific signals, and stage-dependent therapeutic windows (114). For diseases characterized by matrix remodeling or immune suppression, including pulmonary fibrosis and lung cancer, thera- peutic strategies targeting TREM2- or SPP1-associated macrophage programs, as well as macrophage–stromal signaling axes, are being explored (115). Macrophage-based and other CAR-engineered cellular therapies, together with engineered cytokine-delivery approaches, have also shown activity in preclinical solid-tumor models (116, 117). In hyperinflammatory lung injury, macrophage- targeted nanodelivery systems designed to modulate metabolic or epigenetic regulators may provide a preclinical strategy to reduce inflammatory signaling while preserving host defense, although clinical translation remains at an early stage (118). Moving forward, integration of single-cell transcriptomics, spatial metabolomics, single-cell proteomics, and functional per- turbation will be needed to construct more reliable spatiotemporal atlases of pulmonary disease. Computational methods and artificial intelligence may help identify macrophage-associated digital bio- markers, but such biomarkers must be validated across cohorts, species, platforms, and clinically meaningful endpoints. Ultimately, the therapeutic value of macrophage atlases will depend on whether disease-associated macrophage states can be linked to defined tissue niches, disease stages, functional mechanisms, and clinically actionable therapeutic windows.

  generalfuture work
  Keywords: macrophage disease therapeutic associated pulmonary lung single cell review editing spatiotemporal strategies host defense tissue
• The CGRP-nociceptor axis in cancer: tumor-specific programs of immune evasion, stromal remodeling, and tumor growth (2026) · Frontiers in Oncology · doi

  Three controversies cut across the available literature: whether effects of broad nociceptor interventions can be assigned specifically to CGRP, whether receptor-component expression identifies a functionally responsive cell, and whether CGRP-mediated immune suppression predicts reversal of ICB resistance. Resolving these questions requires tumor-specific causal experiments and human pharmacodynamic validation rather than extrapolation from a shared upstream signal alone. Immune suppression is not specific to CGRP signaling. In colorectal cancer, macrophage-derived SPP1 suppresses CD8 T cell function through CD44-associated signaling (27). In hepato- cellular carcinoma, ANXA2 supports CD63-dependent incorpora- tion of PD-L1 into exosomes, which inhibit T cell activation (28). KRAS-mutant lung adenocarcinoma provides a tumor-intrinsic example in which ETV4 promotes PD-L1 expression (29). These mechanisms offer alternative explanations for immune dysfunction and poor treatment response. Studies of CGRP should therefore test its contribution alongside other local suppressive programs; shared immune endpoints alone cannot establish that these pathways belong to the same neural circuit. 7.1 Define the responding cell in each tumor Future studies should combine lineage-restricted receptor per- turbation, spatial profiling, and functional rescue to determine which cell actually receives CGRP. Whole-body Calca or Ramp1 deletion is informative but cannot by itself separate neuronal, immune, stromal, vascular, and tumor-cell effects. Reporting cancer type, disease stage, model, receptor-positive cell, intervention, and measured downstream output should become a minimum standard. Global Calca deletion can alter peptide availability across anatomically distinct neuronal and non-neuronal sources, whereas global Ramp1 deletion affects immune, stromal, vascular, and malignant compartments and may change baseline physiology before tumor implantation. Conditional and inducible alleles, bone-marrow chimeras, adoptive-transfer designs, local pharma- cology, and compartment-specific rescue experiments are needed to separate neuronal production from immune-, stromal-, vascular-, and tumor-cell reception. Cell-resolved analyses can help distinguish these mechanisms. Integrated single-cell and spatial profiling has identified arginine- metabolism-associated mast-cell heterogeneity in breast cancer (30), while transcriptomic and single-cell analyses have linked GBP4-related programs to prognosis and cellular states in pancre- atic adenocarcinoma (31). Single-cell profiling of colorectal cancer has likewise described diverse immune and stromal populations and inferred communication between them (32). Applied to CGRP research, such approaches could locate ligand sources and recep- tor-competent targets within competing microenvironmental pro- grams. However, inferred ligand-receptor interactions and prognostic signatures require validation in the relevant cell com- partment; functional results for another gene do not establish CGRP dependence. 7.2 Separate neural activation from nerve density More nerve fibers do not necessarily mean greater CGRP release, and acute neural activity may be biologically important even without a density change. Studies should measure structural innervation together with neuronal activation, local CGRP release, receptor engagement, and the proposed cellular output. This is especially important when smoking, nutrient deprivation, treat- ment stress, or cancer pain may acutely activate sensory circuits (11, 12, 14, 26). 7.3 Build a translational evidence ladder The studies reviewed here do not yet establish clinical antican- cer efficacy for CGRP blockade or nociceptor ablation. Translational development should proceed through pharmacody- namic window studies, tumor-specific biomarker enrichment, and combination trials only where a defined resistance mechanism has been demonstrated. Migraine safety data can inform starting assumptions, while cancer pain RTX studies inform feasibility of selected neuronal interventions (22, 23, 25); neither substitutes for oncology dose finding, tumor-response endpoints, or long-term safety assessment. Restoring immune recruitment offers a complementary thera- peutic direction. Oncolytic viruses combine tumor-cell lysis with immune activation and can be engineered to deliver immunomod- ulatory signals (33). In syngeneic colorectal cancer models, a CCL19-expressing recombinant influenza virus increased immune infiltration, inhibited tumor growth and metastasis, and induced

  generalfuture work
  Keywords: cell immune cgrp tumor cancer neuronal speci receptor activation stromal whether colorectal cellular local establish
• Deep spatial proteomics reveals a suppressive immune niche linked to immune evasion in renal cell carcinoma (2026) · Cancer Drug Resistance · doi

  A critical distinction must be made between prognostic and predictive biomarkers. Our entire cohort (N = 834) comprises exclusively treatment-naïve patients; therefore, the Spatial Interaction Score is established here as a prognostic biomarker associated with OS, not a validated predictive biomarker for response to ICB. While the biological rationale linking the suppressive niche to ICB resistance is compelling, direct demonstration of predictive utility requires validation in ICB-treated cohorts. Specifically, retrospective analysis of pre-treatment biopsies from CheckMate-214 or KEYNOTE-426 trial participants would provide an ideal testing ground. All discussion of immunotherapy resistance in this manuscript should therefore be interpreted as hypothesis-generating rather than as established clinical evidence. Second, our definition of Tregs relies on CD4+FOXP3+ co-expression. Although FOXP3 is the canonical Treg marker, transient FOXP3 expression can occur in activated conventional CD4+ T cells. To address this concern, we performed orthogonal validation using an independent pan-cancer CD4+ T cell scRNA-seq atlas, demonstrating that FOXP3+ cells in the ccRCC microenvironment co-express a comprehensive panel of canonical Treg markers (IL2RA, CTLA4, IKZF2, TNFRSF18, TIGIT, ENTPD1), confirming their identity as true Tregs [Supplementary Figure 6]. Nevertheless, the inclusion of additional markers such as Helios and CD25 in future mIF panels would enable more precise Treg functional subtyping. Third, our post hoc analysis of PD-1 expression within the niche revealed only a modest protein-level elevation (Cohen’s d = 0.24; Supplementary Figure 5), and the Xenium spatial transcriptomic analysis further showed that PDCD1 transcript levels were paradoxically lower inside the niche (Cohen’s d = -0.09; Supplementary Figure 7). This apparent discrepancy between protein and transcript levels is consistent with the known post-transcriptional regulation of PD-1: PD-1 protein has a long surface half-life and accumulates on the membrane even after transcriptional downregulation, whereas PDCD1 mRNA reflects the current transcriptional state of the cell. The naive/memory-like transcriptomic profile of niche-resident CD8+ T cells (low PDCD1 transcription) coupled with modest protein-level retention is therefore biologically coherent and does not represent a true contradiction. While these findings support our conclusion that the suppressive mechanism is PD-1-independent, they also highlight that PD-1 was not incorporated into the Interaction Score itself. Future iterations of PhenoSSP that integrate PD-1 status into the scoring framework may enable a more granular characterization of effector cell functional states and help distinguish exhausted from bystander CD8+ T cells within the niche. Page 20 of 23 Zhang et al. Cancer Drug Resist. 2026;9:19 Fourth, our primary spatial analysis is derived from a cohort processed on a single mIF platform.

  generallimitationsevidence 5/5
  Keywords: niche foxp cells protein predictive spatial expression treg cell supplementary pdcd transcriptional prognostic cohort treatment

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