Table 1. Cytokines in autism spectrum disorders.

A variety of independent clinical studies have linked cytokines to ASD. This table presents detailed findings for each individual cytokine. Often multiple cytokines were associated with ASD in a single study, which is noted in parentheses.

Cytokine	Findings in autism	Reference
IL-1Β	Elevated plasma levels in children with ASD, correlated with regressive onset. (IL-6, IL-8 and IL-12p40 also elevated)	(Ashwood, Krakowiak et al. 2011)
	Elevated plasma levels in high functioning children with ASD. (IL-1RA, IL-5, IL-8, IL-12p70, IL-13, IL-17 and GRO-α also elevated)	(Suzuki, Matsuzaki et al. 2011)
	Elevated plasma levels in adults with severe ASD. (IL-6 and endotoxin levels also elevated)	(Emanuele, Orsi et al. 2010)
	Peripheral blood cells from ASD subjects produce higher baseline levels. (Similar trends for IL-6 and TNF-α)	(Jyonouchi, Sun et al. 2001)
	Peripheral blood cells from ASD subjects produce higher levels with TLR2 or TLR4 stimulation, and lower levels with TLR-9 stimulation. (Similar trends for IL-6 and TNFα)	(Enstrom, Onore et al. 2010)
IL-6	Elevated plasma levels in children with ASD, correlated with regressive onset. (IL-1Β, IL-8, and IL-12p40 also elevated)	(Ashwood, Krakowiak et al. 2011)
	Elevated plasma levels in adults with severe autism. (IL-Β and endotoxin levels also elevated)	(Emanuele, Orsi et al. 2010)
	Peripheral blood cells from ASD subjects produce higher baseline levels. (Similar trends for IL-1Β and TNF-α)	(Jyonouchi, Sun et al. 2001)
	Peripheral blood cells from children with ASD produce higher levels with TLR2 or TLR4 stimulation, and lower levels with TLR-9 stimulation. (Similar trends for IL-6 and TNFα	(Enstrom, Onore et al. 2010)
	Lymphoblasts from ASD subjects produce more IL-6. (Also TNF-α)	(Malik, Sheikh et al. 2011)
	Increased IL-6 staining in postmortem cerebellar sections from ASD subjects	(Wei, Zou et al. 2011)
	Increased IL-6 in postmortem brain specimens (various regions) from ASD subjects. (Also increased TGF-Β and inflammatory chemokines).	(Vargas, Nascimbene et al. 2005)
	Increased IL-6 in postmortem brain tissue from ASD subjects. (Also increased TNF-α, IFN-γ, GM-CSF, and IL-8)	(Li, Chauhan et al. 2009)
IL-4	Increased IL-4 in mid-gestational serum samples from mothers giving birth to a child with ASD. (Also IL-5 and IFN-γ)	(Goines, Croen et al. 2011)
	Increased IL-4 in amniotic fluid samples from mothers giving birth to a child with ASD (Also IL-10, TNF-α and TNF-Β)	(Abdallah, Larsen et al. 2011)
	Peripheral blood cells from ASD subjects stimulated with PMA-ionomycin were more likely to be IL-4+ (And less likely to be IFN-γ+)	(Gupta, Aggarwal et al. 1998)
IFN-γ	Increased IFN-γ in mid-gestational serum samples from mothers giving birth to a child with ASD. (Also IL-4 and IL-5)	(Goines, Croen et al. 2011)
	Increased plasma levels in individuals with ASD. (Also IL-12)	(Singh 1996)
	Peripheral blood cells stimulated with PMA-ionomycin are less likely to be IFN-γ+ (And more likely to be IL-4+)	(Gupta, Aggarwal et al. 1998)
	Unstimulated whole blood from ASD subjects produced significantly more IFN-γ compared to controls. (Also increased IL-1RA, IL-6, and TNF-α)	(Croonenberghs, Bosmans et al. 2002)
	NK cells from children with ASD produced higher IFN-γ under resting conditions, and lower levels after stimulation. (Also observed with perforin and granzyme B)	(Enstrom, Lit et al. 2009)
	Increased IFN-γ in post mortem brain specimens from ASD subjects. (Also increased TNF-α, IL-6, GM-CSF, and IL-8)	(Li, Chauhan et al. 2009)
TGF-Β	Decreased plasma TGF-Β in children with ASD. Lower levels correlated with more severe behavioral scores.	(Ashwood, Enstrom et al. 2008)
	Decreased serum TGF-Β in adults with ASD.	(Okada, Hashimoto et al. 2007)
	Increased TGF-Β levels in postmortem brain specimens (various regions) from ASD subjects. (Also IL-6 and inflammatory chemokines)	(Vargas, Nascimbene et al. 2005)