Li, Ting

BACKGROUND Obesity is a multifactorial disease with adverse health implications including insulin resistance (IR). In patients with obesity, the presence of high circulating levels of leptin, deemed hyperleptinemia, is associated with IR. Recent data in mice with diet-induced obesity (DIO) show that a partial reduction in leptin levels improves IR. Additional animal studies demonstrate that IL-4 decreases leptin levels. In rodents, resident adipose tissue eosinophils (AT-EOS) are the main source of IL-4 and are instrumental in maintaining metabolic homeostasis. A marked reduction in AT-EOS content is observed in animal models of DIO. These observations have not been explored in humans. METHODS We analyzed AT from individuals with obesity and age-matched lean counterparts for AT-EOS content, IL-4, circulating leptin levels, and measures of IR. RESULTS Our results show that individuals with obesity ( n = 15) had a significant reduction in AT-EOS content ( P < 0.01), decreased AT–IL-4 gene expression ( P = 0.02), and decreased IL-4 plasma levels ( P < 0.05) in addition to expected IR ( P < 0.001) and hyperleptinemia ( P < 0.01) compared with lean subjects ( n = 15). AT-EOS content inversely correlated with BMI ( P = 0.002) and IR ( P = 0.005). Ex vivo AT explants and in vitro cell culture of primary human mature adipocytes exposed to either IL-4 or EOS conditioned media produced less leptin ( P < 0.05). CONCLUSION Our results suggest that IL-4 acts as a link between EOS, AT, and leptin production. Future studies exploring this interaction may identify an avenue for the treatment of obesity and its complications through amelioration of hyperleptinemia. TRIAL REGISTRATION Clinicaltrials.gov NCT02378077 & NCT04234295.

Abstract The three-dimensional (3D) structure of the cell and its nucleus is intricately associated with cellular function. Aberrations and heterogeneity in cellular and nuclear morphology serve as diagnostically important cues to identify malignant transformation. However, current cytopathology practice is predominantly based on a qualitative, 2D assessment of cellular morphology that may bias the diagnosis. We utilized the Cell-CT® platform to perform single-cell, optical tomography imaging and generate 3D cell images with isotropic, sub-micron spatial resolution. We developed custom image analysis tools to accurately quantify 3D cell and nuclear morphology. We used these measures to characterize the morphological heterogeneity within and among epithelial cell populations, and to identify morphological descriptors that are reliably predictive of cell state. We assessed the efficacy of our approach relative to conventional 2D assessment (at 40x magnification) to detect malignant transformation in immortalized and primary normal-cancer cell line pairs from human esophagus and breast epithelia. We observed the 3D method of assessment to provide a consistently superior performance (sensitivity and specificity) in predicting malignant transformation. Further, some widely used diagnostic parameters, such as nuclear size or nucleus-to-cytoplasm ratio, did not always exhibit the highest predictive power in 3D space. The availability of 3D morphological information also provided novel insights on intra-population morphological heterogeneity in both normal and cancer cell populations. Our results emphasize the need to incorporate 3D morphological information into standard pathological practice. Citation Format: Vivek Nandakumar, Stephanie Helland, Jessica H. Han, Geriann Davis, Brian A. Ashcroft, Thai H. Tran, Ting Li, Karen S. Anderson, Rahul Pannala, Joseph R. Mikhael, David E. Fleischer, Roger H. Johnson, Kimberly J. Bussey, Deirdre R. Meldrum. Quantifying three-dimensional cellular morphology and its heterogeneity in epithelial cancers by single-cell optical tomography. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4297. doi:10.1158/1538-7445.AM2014-4297