Obesity Impairs Immune Cells Against Infection and Cancer
Obesity impairs the function of specialized immune cells responsible for protecting the body against infections and cancer, according to research published in JCI Insight. Over one billion adults worldwide live with obesity, which is linked to a greater risk of severe outcomes from viral and bacterial infections, such as during the COVID-19 pandemic. Researchers at Maynooth University examined gamma delta T cells—specifically Vδ2+ T cells—to understand why individuals with obesity face heightened immunological vulnerabilities.
The study found that individuals living with obesity possess fewer Vδ2+ T cells in their blood. These cells also display reduced activity upon stimulation and exhibit metabolic abnormalities that restrict nutrient uptake and energy production. Without adequate energy metabolism, the immune system cannot mount an effective defense against invading pathogens or malignant cells.
Bariatric Surgery Restores Immune Function
Roux-en-Y gastric bypass (RYGB) surgery reverses many of the immune cell defects caused by obesity, according to the Maynooth University research group led by Dr. Ciara Flynn and Prof. Andrew Hogan within the Kathleen Lonsdale Institute for Human Health Research. Patients undergoing RYGB demonstrated significant metabolic improvements that supported the recovery of immune cell function.
The study notes that successful surgical treatment of obesity restores the body’s natural defenses. New research indicates that bariatric surgery helps explain why post-surgical patients experience a 40% to 50% lower chance of developing cancer and other obesity complications.
Translational Research Findings on Metabolism and Immunity
Complementary findings regarding adipose tissue emphasize that chronic caloric overload leads to systemic metabolic compromise, insulin resistance, and type 2 diabetes when adipose tissue becomes dysfunctional. While some research models cellular atlases of murine white adipose tissue following vertical sleeve gastrectomy or GLP-1 receptor agonist treatment like semaglutide, the Maynooth University study zeroes in on the direct metabolic starvation of circulating immune defenses.
Prof. Andrew Hogan stated that the findings explain why individuals with obesity show increased vulnerability to serious infections and other conditions. Professor Paul Moynagh, Director of the Kathleen Lonsdale Institute for Human Health Research, described the study as an impactful example of translational research combining scientific and clinical expertise.
Frequently Asked Questions About Obesity and Immune Cell Recovery
What specific immune cells are affected by obesity?
Research published in JCI Insight identifies gamma delta T cells, specifically a subset known as Vδ2+ T cells, as the primary population impaired by obesity. These cells form part of the body’s first line of defense by responding rapidly to infections and helping destroy cancer cells.
How does obesity damage these immune defenses?
Obesity disrupts the metabolic processes that control nutrient uptake and energy production within Vδ2+ T cells. This metabolic bottleneck leaves the cells without the necessary energy to mount a strong response when exposed to viral or bacterial threats.
Does weight loss through any method restore immune function?
The published study specifically evaluated patients who underwent Roux-en-Y gastric bypass surgery, which successfully reversed the immune cell defects and restored metabolic pathways supporting immune responsiveness. Other weight-loss interventions, such as vertical sleeve gastrectomy and GLP-1 receptor agonists, alter adipose tissue phenotype and glucose homeostasis as detailed in comparative cellular research on white adipose tissue.
Who funded and conducted the Maynooth University study?
The Health Research Board funded the research, which was led by Dr. Ciara Flynn and Prof. Andrew Hogan at Maynooth University’s Department of Biology in collaboration with Prof. Helen Heneghan and Prof. Donal O’Shea at St. Vincent’s University Hospital and University College Dublin.
Worth a look