Receptor inhibition by immunoglobulins: specific inhibition by autistic children, their relatives, and control subjects.
Autistic kids do not carry unique antibodies that block serotonin receptors, so immune-based explanations for autism remain unproven.
01Research in Context
What this study did
Scientists drew blood from 20 autistic kids, 20 of their brothers or sisters, 20 moms, 20 dads, and 20 control children.
They mixed each plasma sample with lab-grown cells that carry serotonin receptors.
If the plasma blocked the receptor, the team recorded how much inhibition occurred.
What they found
Plasma from every group blocked the receptors a little, but the amount was the same across groups.
Autistic children showed no special "auto-antibody" that others lacked.
The idea that unique antibodies cause autism was not supported.
How this fits with other research
Dubuque (2015) later warned that all autism biomarker tests, including this one, are still too shaky for clinic use.
Nevin et al. (2005) reviewed gut-immune claims and also found weak evidence, matching the null result here.
Lord et al. (2005) pushed for tougher designs like RCTs; this 1993 quasi-study is exactly the weaker pre-RCT evidence they critique.
Why it matters
You can safely skip immune-based fad treatments that cite "autistic antibodies." Focus your energy on behavior plans with solid data instead. When parents ask about pricey antibody tests, show them this study and the later reviews that agree: biological shortcuts are not ready for prime time.
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02At a glance
03Original abstract
Forty-two parents of children with autistic disorder, 15 children with autistic disorder, 17 siblings of children with autistic disorder, and 12 unrelated normal adult controls were studied to determine if immunoglobulins isolated from their plasma would inhibit binding of the 5HT1A agonist, [3H]-8-hydroxy-N,N-dipropyl-2-aminotetralin (DPAT) to 5HT1A receptors in human hippocampal membranes. There were no significant differences among the means of percentage inhibition of DPAT binding of parents, children with autistic disorder, siblings, or unrelated controls. In addition, there were no differences in the proportion of subjects with > 15% DPAT inhibition among autistic children, their parents, their siblings, or unrelated controls. Immunoglobulin inhibition was not specific for the 5HT1A receptor binding site, since immunoglobulins inhibited binding to 5HT2, D1, D2, and alpha 2-adrenergic binding sites. The immunoglobulins isolated from normal controls inhibited [3H]-rauwolscine binding at alpha 2-adrenergic sites less than immunoglobulins of children with autistic disorder and their parents and siblings. This study did not support the hypothesis that autoantibodies to 5HT1A or 5HT2 receptors are characteristic of autistic disorder.
Journal of autism and developmental disorders, 1993 · doi:10.1007/BF01066419