All articles tagged with #immune system
Tattoo pigments provoke an immune response in the skin, can migrate to lymph nodes, and often contain metals and colorants that may break down into potentially harmful compounds; while there is not yet strong evidence of a direct cancer risk in humans, colored inks can cause allergic reactions and chronic inflammation, highlighting the need for better ink regulation and further research.
New research shows that ovaries don’t simply stop after menopause; in mice, aging ovaries transition from reproductive function to an immune-dominant profile with increased immune cell activity, suggesting post-reproductive ovaries may influence aging and health. Human tissue data align with this immune shift, challenging the idea of inert postmenopausal ovaries and implying potential implications for healthcare and people who have had ovaries removed.
Researchers sequenced 177 Near Oceanian genomes and found that 3,127 Denisovan-derived variants remain functional in modern humans, many affecting immune signaling (notably interferon-gamma). Some Papua New Guinean populations carry up to ~5% Denisovan ancestry, reflecting interbreeding with multiple Denisovan-related groups and underscoring the health relevance of archaic DNA.
A large, first-of-its-kind map of Denisovan-derived DNA in Oceanian populations identified about 3,127 variants that still influence immune-system genes today; many are unique to Oceania, and natural selection increased their frequency in Near Oceania, suggesting Denisovan DNA helped defend against novel pathogens, though the exact benefits vary and researchers say more Oceanian genome sequencing is needed to fully understand health implications.
An NEJM study suggests adult thymus removal may double five‑year mortality and cancer risk, highlighting the gland’s potential health role and prompting caution to preserve it when possible. However, a 2025 Yale analysis found no clear harm from thymectomy, and researchers stress that the findings are observational and not causal, signaling the need for more research to understand the true impact.
As men age, some cells can lose the Y chromosome, a change linked to higher risks of cancer, kidney and heart disease, Alzheimer's, and earlier death. Evidence from human studies and mouse models shows Y loss may impair immune function and cancer defense, and a sizable share of older men harbor Y-loss in tissues such as blood and tumors (e.g., bladder cancer). Ongoing debate asks how essential Y genes are and whether other chromosomes can compensate, though the chromosome has shrunk to roughly 3% of its ancestral genes and may not be doomed to vanish.
A study of 1,864 people with major depressive disorder and 1,208 controls found 1,383 genes with altered activity in white blood cells, including 18 synapse-related genes that reliably separated depressed individuals from healthy ones. Seven of these genes were also altered in mood-related brain regions, suggesting a systemic, body-wide link between depression and immune biology. The work is exploratory and does not establish causation, but points to potential blood-based biomarkers and new avenues for research and treatment targeting inflammation.
A tiny subset of HIV-positive people—elite controllers—can suppress the virus without antiretroviral therapy. Case studies like Loreen Willenberg and the Esperanza patient show their immune systems, particularly CD8+ T cells and highly active natural killer cells, may trap HIV in dormant gene deserts, offering a blueprint for a functional cure. The research also highlights post-treatment controllers and a possible female-biased tendency in this response, underscoring how understanding these rare defenses could guide new therapies for millions living with HIV.
A dietitian explains why she takes a daily vitamin D to maintain sufficient levels, noting that benefits are greatest when correcting a deficiency rather than adding to already sufficient levels. Evidence suggests adequate vitamin D supports bone health, immune function, and respiratory health, and may lower all-cause mortality risk in deficient individuals. Those with sufficient levels may not notice daily improvements, and excessive dosing can lead to hypercalcemia, so vitamin D supplementation should be guided by medical advice.
A major review in Addiction synthesizes decades of evidence showing alcohol contributes to dozens of diseases and injuries across nearly every organ, weakens immune defenses and raises infection risk, and while some harms can lessen with reduced or stopped drinking, many damages persist; potential heart benefits of light drinking remain disputed.
A meta-analysis and related studies flag that vitamin D2 supplements can lower circulating vitamin D3, the more effective form, while vitamin D3 appears to better support immune function. The findings prompt consideration that D3 could be the preferred supplement for most people, though individual needs and further research remain important.
Chronic stress triggers the body’s fight‑or‑flight response with adrenaline and cortisol, boosting energy in the moment but diverting resources from digestion, repair and immunity when it’s constant. This can raise infection risk, obesity, depression and may influence neurodegenerative processes; individual tolerance varies with life experience and resilience. For acute stress, slow, regulated breathing and regular exercise can dampen the response, while chronic stress may require therapies like CBT or mindfulness plus lifestyle changes and social support. If stress is persistent, seek help and reduce unnecessary stressors (e.g., social media, unsolvable conflicts).
Pneumonia is a leading cause of hospitalization, with adults 65 and older about 10 times more likely to be hospitalized and severe cases carrying mortality up to around 20%. The danger comes from both the infecting pathogen and an aging, often multi‑ill, immune system. Vaccines (flu, pneumococcal, COVID‑19, RSV) and managing chronic conditions can reduce risk, while lifestyle choices (hydration, nutrition, exercise, avoiding smoking) and general infection control (hand hygiene, staying home when sick, masking around vulnerable people) also help protect older adults.
Muscles release signaling molecules called myokines when they contract, influencing immune function, brain health, metabolism, bones, and cardiovascular health. Exercise elevates myokines (e.g., IL-6, irisin, BDNF) and exerkines, promoting fat loss, insulin sensitivity, neuroplasticity, immune surveillance, bone remodeling, and even cancer suppression. A sedentary lifestyle raises disease risk, making regular movement essential for overall health.
Scientists are reframing the thymus—a two-lobed gland behind the breastbone—as a central regulator of aging and immune health, with healthier thymuses linked to longer lifespans, lower cancer and heart-disease risk, and better responses to cancer immunotherapy; researchers are pursuing thymus rejuvenation and engineered thymic tissue to boost vaccines and transplant tolerance.