Karishma Bhatia and Sanjeev K Upadhyay*

Pharmacology Lab, Department of Biochemistry, The Maharaja Sayajirao University of Baroda, Vadodara Gujarat, India

*Corresponding Author: Sanjeev K Upadhyay, Pharmacology Lab, Department of Biochemistry, The Maharaja Sayajirao University of Baroda, Vadodara Gujarat, India. sanjeev.kumar-biochem@msubaroda.ac.in

Received: July 19, 2026; Published: August 11, 2026

Obesity has emerged as a critical global epidemic, significantly increasing the risk for metabolic conditions such as type 2 diabetes and cardiovascular diseases. Apart from functioning as an energy storage site, adipose tissue operates as an active endocrine organ involved in immune system regulation. During nutrient excess, abnormal expansion of white adipose tissue leads to systemic metabolic dysfunction, lipotoxicity, hypoxia, and a state of chronic, low-grade sterile inflammation known as meta-inflammation. This review examines the cellular shifts within adipose tissue during obesity, characterized by a loss of protective type 2 immune cells (such as M2 macrophages) and an influx of pro-inflammatory subsets including CD8+ T cells, neutrophils, and M1-like macrophages. Adipose tissue macrophages accumulate around dying adipocytes to form crown-like structures, undergoing metabolic activation and driving inflammatory cytokine production. This dynamic crosstalk between macrophages and adipocytes establishes a paracrine feedback loop involving free fatty acids and inflammatory mediators, which disrupts insulin signaling and mitochondrial bioenergetics. Understanding these intricate immunological alterations and macrophage polarization pathways in dysfunctional adipose tissue highlights potential therapeutic targets for mitigating obesity-associated metabolic disorders.

Keywords: Obesity; Diabetes Type 2; Immuno-Metabolism; Macrophages; Immune Cells

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Citation

Citation: Karishma Bhatia and Sanjeev K Upadhyay. “Immune Cells in Adipose Tissue and Obesity". Acta Scientific Medical Sciences 10.9 (2026): 31-44.

Copyright

Copyright: © 2026 Karishma Bhatia and Sanjeev K Upadhyay. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.