Table 1.

Table. Compiled Results of Observational and Behavioral Studies Associating Maternal Antibodies With Autism^a

Antibody Target	MW	Prevalence, %	Maternal IgG Population, No.
Observational Studies
Child/paternal lymphocytes²⁵	Undetermined	54 (against child’s or father’s cells)	AU = 11; TD = 20
Rat fetal/juvenile/adult brain²⁶	Multiple low MW and 250 kDa	100 (2 patterns)	AU = 11; TD = 10
Human fetal brain²⁷	37 kDa and 73 kDa pair	12	AU = 61; DD = 40; TD = 62
Human fetal brain²⁸	39 kDa and 39 kDa/73 kDa pair	7 (for 39 kDa)	AU = 84; DD = 49; TD = 160
Fetal/adult human and rat brain²⁹	36 kDa, 39 kDa, and 61 kDa	10 (36 kDa for human fetal brain)	AU = 100; TD = 100
Fetal rhesus macaque brain³⁰	37 kDa/73 kDa and 39 kDa/73 kDa pairs	7 (37/73 kDa) and 4 (39/73 kDa)	AU = 201; ASD = 71; TD = 185; DD = 102

Species	Significant Outcomes	Administration Route; Gestational Age; Amount per Injection; Serum or IgG	Maternal IgG Population
Animal Behavioral Studies
Rat³¹	Decreased exploration Impaired motor control IHC Purkinje/neuroblastoma staining Decreased choline and creatinine levels	Intraperitoneal; embryonic day (for rodents) 10–17; 0.5 mL; serum	AU = 1; TD = 4 (all multiplex)
Rhesus macaque³²	Reduced peer contact Increased nonsocial activity Hyperactivity Whole-body stereotypies	Intravenous; gestational day (for primates) 27, 41, and 55; 15–20 mg; IgG	AU = 12; TD = 7 (all multiplex)
Mouse²⁴	Hyperactivity Increased anxiety Reduced social interaction Embryonic day 18 microglial activation Increased brain BDNF levels	Intraperitoneal; embryonic day 13–18; 1.25–1.4 mg; IgG	AU = 63; TD = 63 (mixed parity)

Abbreviations: ASD, autism spectrum disorder; AU, autism; BDNF, brain-derived neurotrophic factor; DD, developmental delay (nonautism); MW, molecular weight; TD, typically developing.

Observational studies of maternal antibody binding to fetal brain proteins have often noted maternal IgG reactivity to antigens of approximately 36 to 39 kDa, focusing candidate protein identification on this MW range. Behavioral studies have recapitulated some of the features of autism in model systems and have yielded substantially consistent results.