Cole · Proceedings of the National Academy of Sciences of the United States of America 2015 · Longitudinal cohort study and animal experimental model · n=141 humans (macaque n not reported)

Myeloid differentiation architecture of leukocyte transcriptome dynamics in perceived social isolation.

Cited 317 times in the scientific literature.

Level 3 - non-randomized controlled study

Longitudinal cohort study in humans combined with an animal mechanistic model

PubMed 26598672 · doi:10.1073/pnas.1514249112 · record verified 2026-08-27

What was done

Integrative analyses of leukocyte gene regulation were conducted across five longitudinal leukocyte transcriptome surveys in 141 older adults experiencing perceived social isolation (loneliness). Parallel mechanistic experiments were conducted in a rhesus macaque model of perceived social isolation evaluating immune responses and response to simian immunodeficiency virus (SIV) infection.

What was found

In 141 older adults, perceived social isolation was associated with up-regulation of sympathetic nervous system (SNS) signaling, expansion of the monocyte population, and up-regulation of the leukocyte conserved transcriptional response to adversity (CTRA). In the macaque model, perceived social isolation confirmed CTRA activation, demonstrated selective up-regulation of the CD14(++)/CD16(-) classical monocyte transcriptome, functional glucocorticoid desensitization, down-regulation of Type I and Type II interferons, and impaired immune response to SIV infection. Specific numerical effect estimates and variance metrics were not provided in the abstract.

Why it matters

The study outlines a cellular pathway connecting social adversity to physical illness, demonstrating that loneliness skews myeloid differentiation toward a pro-inflammatory, antiviral-deficient phenotype via neuroendocrine signaling.

Limits

The human component is observational and limited to older adults, precluding independent establishment of causality in humans. Exact statistical metrics, effect magnitudes, and the number of macaques used were not reported in the abstract.

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