Immunological features of Down's syndrome: a review.
Down syndrome brings early, lifelong immune imbalance that can hide behind behavior changes you see in session.
01Research in Context
What this study did
Cohen et al. (1993) pulled together every paper they could find on the immune systems of people with Down syndrome.
They looked at antibody levels, T-cell counts, and how well white blood cells responded to germs.
The review covers birth through early adulthood, but most data come from kids over six.
What they found
After age six, many children show too much IgG and IgA antibody in their blood.
CD8 "killer" T-cells rise while CD4 "helper" T-cells stay flat, upsetting the normal balance.
When lab techs add a germ mimic, the white cells grow weaker each year, showing the immune system tires faster.
How this fits with other research
Yin et al. (2025) widens the picture. Their huge Danish registry shows heart, lung, and autoimmune problems stay common into adulthood, so the immune quirks L et al. described keep mattering later in life.
Bauman et al. (1996) and Kleinert et al. (2007) seem to disagree. The first team saw little cognitive loss before age 55, while the second found dementia in one of every five adults. The gap is time: short-term versus fifteen-year follow-up. Immune decline may start early, but brain decline accelerates after mid-50s.
Taken together, immune dysregulation is an early warning sign, not a one-time childhood issue.
Why it matters
You can add simple health checks to behavior plans. Watch for frequent colds, slow wound healing, or unusual fatigue after sessions. These may signal the same weak cell responses L et al. flagged. Share the pattern with the medical team so illness does not masquerade as "problem behavior." Adjust teaching intensity when clients show signs of infection and build extra practice trials for self-care skills like hand-washing.
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02At a glance
03Original abstract
Young patients with Down's syndrome (DS) have high rates of infections, malignancies and autoimmune phenomena. Therefore, DS may be considered as a model of precocious, abnormal ageing of the thymus-dependent system in man. In DS children less than 6 years of age, the levels of serum immunoglobulins did not differ from healthy controls, but after that age, considerable hyper-IgG and -IgA were found. Furthermore, high levels of IgG1 and IgG3 have been found, whereas a progressive decline of IgG2 and IgG4 with age has been observed. The frequency of hepatitis B virus carriers even in the youngest age group is much higher among DS children. It has been reported that an IgG response was detectable in 75% of controls after HBsAg vaccination as compared to the 16.6% of DS patients. The presence of autoantibodies against human thyroglobulin did show a positive association with HB Virus Ag carriers, but only in the oldest DS subjects. Natural antibodies against intestinal antigens are low, while in the presence of cow's milk, abnormally high titres against casein and beta-lactoglobulin were present. High levels of IgG antibodies against gliadin have been observed. In spite of a normal percentage of CD3- and CD2-positive lymphocytes, a high proportion of cells express low-avidity receptors for sheep erythrocytes. Although the proportion of CD4+ T-lymphocyte helper-cells is normal, a marked imbalance in the CD4+ subpopulations has been documented. The percentage of suppressor-cytotoxic CD8+ lymphocytes is markedly increased. The responses to phytohemagglutinin and concanavalin A are within the normal range in the first decade of life and decline progressively thereafter. A recent study reported defective proliferative response to allo-mixed lymphocyte culture, with decreased expression of the membrane CD25, low secretion of interleukin 2 in the supernatant and depressed allo-specific cytotoxic activity.(ABSTRACT TRUNCATED AT 250 WORDS)
Journal of intellectual disability research : JIDR, 1993 · doi:10.1111/j.1365-2788.1993.tb00324.x