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Biology subjects

Humayun, M.

Publications and source records attributed to Humayun, M..

5 recordsLinked to original sources

Patient-Specific Vascularized Tumor Model: Blocking TAM Recruitment with Multispecific Antibodies Targeting CCR2 and CSF-1R

Tumor-associated inflammation drives cancer progression and therapy resistance, with the infiltration of monocyte-derived tumor-associated macrophages (TAMs) associated with poor prognosis in diverse cancers. Targeting TAMs holds potential against solid tumors, but effective immunotherapies require testing on immunocompetent human models prior to clinical trials. Here, we develop an in vitro model of microvascular networks that incorporates tumor spheroids or patient tissues. By perfusing the vasculature with human monocytes, we investigate monocyte trafficking into the tumor and evaluate immunotherapies targeting the human tumor microenvironment. Our findings demonstrate that macrophages in vascularized breast and lung tumor models can enhance monocyte recruitment via TAM-produced CCL7 and CCL2, mediated by CSF-1R. Additionally, we assess a novel multispecific antibody targeting CCR2, CSF-1R, and neutralizing TGF-{beta}, referred to as CSF1R/CCR2/TGF-{beta} Ab, on monocytes and macrophages using our 3D models. This antibody repolarizes TAMs towards an anti-tumoral M1-like phenotype, reduces monocyte chemoattractant protein secretion, and effectively blocks monocyte migration. Finally, we show that the CSF1R/CCR2/TGF-{beta} Ab inhibits monocyte recruitment in patient-specific vascularized tumor models. Overall, this vascularized tumor model offers valuable insights into monocyte recruitment and enables functional testing of innovative therapeutic antibodies targeting TAMs in the tumor microenvironment (TME).

bioengineering↗

Climate Change Impacts on Broussenetia papyrifera Pollens - Metabolome Investigations and Prospects of Allergy Prevalence

Broussonetia papyrifera (B. papyrifera) is an allergenic plant in the mulberry family that grows at varied elevations and climatic conditions worldwide. In northern Pakistan, B. papyrifera is abundant and it produces a substantial amount of pollen that disperses in the air causing allergies in some humans. Climate change affects pollen production. To investigate potential changes in pollens development and potential allergenicity, B. papyrifera pollens were collected in summer and in spring from different regions in Pakistan. Study samples were subjected to morphological analysis, Fourier Transform Infrared Spectroscopy (FTIR) analysis for biochemical differences, and Liquid Chromatography-Mass Spectrometry (LCMS) for metabolome analysis. Morphological studies of the dried pollen by light microscopy showed seasonal and regional differences in pollens size and exine morphology. FTIR analysis showed inter-regional and inter-seasonal differences in the metabolome of the pollen. Differences in lipid and protein functional groups of pollen from different regions showed variation in the FTIR spectra. These differences in FTIR spectra correlated with the changing climatic conditions. Metabolome analysis of targeted pollen samples identified 33 organic compounds of seven different groups. Four unsaturated fatty acids were identified that have a potential role in allergic responses. The findings in this study are unique in demonstrating climatic variables that effect B. papyrifera pollen physiology (FTIR analysis) which also confirms differences in pollen-associated lipid metabolites identified by LCMS analysis. These results demonstrate information that may be used to predict potential changes in allergy risks from pollens of B. papyrifera in the future. The findings may provide a model for predicting variation in pollen structure and associated allergies in response to climate changes for other species.

scientific communication and education↗

Innate immune cell response to host-parasite interaction in a human intestinal tissue microphysiological system

Protozoan parasites that infect humans are widespread, and lead to varied clinical manifestations, including life-threatening illnesses in immunocompromised individuals. Animal models have provided insight into innate immunity against parasitic infections, however, species-specific differences and complexity of innate immune responses make translation to humans challenging. Thus, there is a need for novel in vitro systems that can elucidate mechanisms of immune control and parasite dissemination. We have developed a human microphysiological system of intestinal tissue to evaluate parasite-immune-specific interactions during infection, which integrates primary intestinal epithelial cells and immune cells to investigate the role of innate immune cells during epithelial infection by the protozoan parasite, Toxoplasma gondii, which affects billions of people worldwide. Our data indicate that epithelial-infection by parasites stimulates a broad range of effector functions in neutrophils and NK cell-mediated cytokine production that play immunomodulatory roles, demonstrating the potential of our system for advancing the study of human-parasite interactions. TeaserNovel engineered model of human intestinal tissue for study of dissemination and immune control of parasitic infections.

bioengineering↗

Under-oil autonomously regulated oxygen microenvironments for cell culture

Oxygen levels in vivo are autonomously regulated by a supply-demand balance, which can be altered in disease states. However, the oxygen levels of in vitro cell culture systems, particularly microscale cell culture, are typically dominated by either supply or demand. Further, the oxygen microenvironment in these systems are rarely monitored or reported. Here, we present a method to establish and dynamically monitor autonomously regulated oxygen microenvironments (AROM) using an oil overlay in an open microscale cell culture system. Using this method, the oxygen microenvironment is dynamically regulated via a supply-demand balance of the system. We simulate the kinetics of oxygen diffusion in multiliquid-phase microsystems on COMSOL Multiphysics and experimentally validate the method using a variety of cell types including mammalian, fungal and bacterial cells. Finally, we demonstrate the utility of this method to establish a co-culture between primary intestinal epithelial cells and a highly prevalent human gut species Bacteroides uniformis.

bioengineering↗

Autofluorescence imaging of 3D tumor-macrophage microscale cultures resolves spatial and temporal dynamics of macrophage metabolism

Macrophages within the tumor microenvironment (TME) exhibit a spectrum of pro-tumor and anti-tumor functions, yet it is unclear how the TME regulates this macrophage heterogeneity. Standard methods to measure macrophage heterogeneity require destructive processing, limiting spatiotemporal studies of function within the live, intact 3D TME. Here, we demonstrate two-photon autofluorescence imaging of NAD(P)H and FAD to non-destructively resolve spatiotemporal metabolic heterogeneity of individual macrophages within 3D microscale TME models. Fluorescence lifetimes and intensities of NAD(P)H and FAD were acquired at 24, 48, and 72 hours post-stimulation for mouse macrophages (RAW 264.7) stimulated with IFN-{gamma} or IL-4 plus IL-13 in 2D culture, validating that autofluorescence measurements capture known metabolic phenotypes. To quantify metabolic dynamics of macrophages within the TME, mouse macrophages or human monocytes (RAW264.7 or THP-1) were cultured alone or with breast cancer cells (mouse PyVMT or primary human IDC) in 3D microfluidic platforms. Human monocytes and mouse macrophages in tumor co-cultures exhibited significantly different FAD mean lifetimes and greater migration than mono-cultures at 24, 48, and 72 hours post-seeding. In co-cultures with primary human cancer cells, actively-migrating monocyte-derived macrophages had greater redox ratios (NAD(P)H/FAD intensity) compared to passively-migrating monocytes at 24 and 48 hours post-seeding, reflecting metabolic heterogeneity in this sub-population of monocytes. Genetic analyses further confirmed this metabolic heterogeneity. These results establish label-free autofluorescence imaging to quantify dynamic metabolism, polarization, and migration of macrophages at single-cell resolution within 3D microscale models. This combined culture and imaging system provides unique insights into spatiotemporal tumor-immune crosstalk within the 3D TME.

bioengineering↗