Search tips
Search criteria

Results 1-8 (8)

Clipboard (0)

Select a Filter Below

more »
Year of Publication
Document Types
1.  Maternal immune activation leads to activated inflammatory macrophages in offspring 
Brain, behavior, and immunity  2014;38:220-226.
Several epidemiological studies have shown an association between infection or inflammation during pregnancy and increased risk of autism in the child. In addition, animal models have illustrated that maternal inflammation during gestation can cause autism-relevant behaviors in the offspring; so called maternal immune activation (MIA) models. More recently, permanent changes in T cell cytokine responses were reported in children with autism and in offspring of MIA mice; however, the cytokine responses of other immune cell populations have not been thoroughly investigated in these MIA models. Similar to changes in T cell function, we hypothesized that following MIA, offspring will have long-term changes in macrophage function. To test this theory, we utilized the poly (I:C) MIA mouse model in C57BL/6J mice and examined macrophage cytokine production in adult offspring. Pregnant dams were given either a single injection of 20 mg/kg polyinosinic–polycytidylic acid, poly (I:C), or saline delivered intraperitoneally on gestational day 12.5. When offspring of poly (I:C) treated dams reached 10 weeks of age, femurs were collected and bone marrow-derived macrophages were generated. Cytokine production was measured in bone marrow-derived macrophages incubated for 24 h in either growth media alone, LPS, IL-4/LPS, or IFN-γ/LPS. Following stimulation with LPS alone, or the combination of IFN-γ/LPS, macrophages from offspring of poly (I:C) treated dams produced higher levels of IL-12(p40) (p < 0.04) suggesting an increased M1 polarization. In addition, even without the presence of a polarizing cytokine or LPS stimulus, macrophages from offspring of poly (I:C) treated dams exhibited a higher production of CCL3 (p = 0.05). Moreover, CCL3 levels were further increased when stimulated with LPS, or polarized with either IL-4/LPS or IFN-γ/LPS (p < 0.05) suggesting a general increase in production of this chemokine. Collectively, these data suggest that MIA can produce lasting changes in macrophage function that are sustained into adulthood.
PMCID: PMC4321784  PMID: 24566386
MIA; Maternal; Immune activation; Macrophage; M1; M2; Mouse; Autism; Behavior; Inflammation
2.  Levels of Soluble Adhesion Molecules PECAM-1 and P-Selectin are Decreased in Children with Autism Spectrum Disorder 
Biological psychiatry  2012;72(12):1020-1025.
Although the etiopathology of Autism Spectrum Disorder (ASD) is not clear there is increasing evidence that dysfunction in the immune system affects many children with ASD. Findings of immune dysfunction in ASD include increases in inflammatory cytokines, chemokines and microglial activity in brain tissue and CSF, as well as abnormal peripheral immune cell function.
Adhesion molecules, such as platelet endothelial adhesion molecule-1 (PECAM-1), intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), P-Selectin, and L-Selectin, function to facilitate leukocyte transendothelial migration. We assessed concentrations of soluble adhesion molecules, sPECAM-1, sICAM-1, sVCAM-1, sP-Selectin, and sL-Selectin in the plasma of 49 participants with ASD, and 31 typically developing controls of the same age, all of whom were enrolled as part of the Autism Phenome Project (APP). Behavioral assessment, the levels of soluble adhesion molecules, head circumference and MRI measurements of brain volume were compared in the same subjects.
Levels of sPECAM-1 and sP-Selectin were significantly reduced in the ASD group compared to typically developing controls (p < 0.02). Soluble PECAM-1 levels were negatively associated with repetitive behavior and abnormal brain growth in children with ASD (p=0.03).
As adhesion molecules modulate the permeability and signaling at the blood brain barrier as well as leukocyte infiltration into the CNS, current data suggests a role for these molecules in the complex pathophysiology of ASD.
PMCID: PMC3496806  PMID: 22717029
Autism; PECAM-1; P-Selectin; CD31; CD62-P; Adhesion
3.  The role of immune dysfunction in the pathophysiology of autism 
Brain, behavior, and immunity  2011;26(3):383-392.
Autism spectrum disorders (ASD) are a complex group of neurodevelopmental disorders encompassing impairments in communication, social interactions and restricted stereotypical behaviors. Although a link between altered immune responses and ASD was first recognized nearly 40 years ago, only recently has new evidence started to shed light on the complex multifaceted relationship between immune dysfunction and behavior in ASD. Neurobiological research in ASD has highlighted pathways involved in neural development, synapse plasticity, structural brain abnormalities, cognition and behavior. At the same time, several lines of evidence point to altered immune dysfunction in ASD that directly impacts some or all these neurological processes. Extensive alterations in immune function have now been described in both children and adults with ASD, including ongoing inflammation in brain specimens, elevated pro-inflammatory cytokine profiles in the CSF and blood, increased presence of brain-specific auto-antibodies and altered immune cell function. Furthermore, these dysfunctional immune responses are associated with increased impairments in behaviors characteristic of core features of ASD, in particular, deficits in social interactions and communication. This accumulating evidence suggests that immune processes play a key role in the pathophysiology of ASD. This review will discuss the current state of our knowledge of immune dysfunction in ASD, how these findings may impact on underlying neuro-immune mechanisms and implicate potential areas where the manipulation of the immune response could have an impact on behavior and immunity in ASD.
PMCID: PMC3418145  PMID: 21906670
4.  Inflammatory macrophage phenotype in BTBR T+tf/J mice 
Although autism is a behaviorally defined disorder, many studies report an association with increased pro-inflammatory cytokine production. Recent characterization of the BTBR T+tf/J (BTBR) inbred mouse strain has revealed several behavioral characteristics including social deficits, repetitive behavior, and atypical vocalizations which may be relevant to autism. We therefore hypothesized that, asocial BTBR mice, which exhibit autism-like behaviors, may have an inflammatory immune profile similar to that observed in children with autism. The objectives of this study were to characterize the myeloid immune profile of BTBR mice and to explore their associations with autism-relevant behaviors. C57BL/6J (C57) mice and BTBR mice were tested for social interest and repetitive self-grooming behavior. Cytokine production was measured in bone-marrow derived macrophages incubated for 24 h in either growth media alone, LPS, IL-4/LPS, or IFNγ/LPS to ascertain any M1/M2 skewing. After LPS stimulation, BTBR macrophages produced higher levels of IL-6, MCP-1, and MIP-1α and lower IL-10 (p < 0.01) than C57 mice, suggesting an exaggerated inflammatory profile. After exposure to IL-4/LPS BTBR macrophages produced less IL-10 (p < 0.01) than C57 macrophages and more IL-12p40 (p < 0.01) suggesting poor M2 polarization. Levels of IL-12(p70) (p < 0.05) were higher in BTBR macrophages after IFNγ/LPS stimulation, suggesting enhanced M1 polarization. We further observed a positive correlation between grooming frequency, and production of IL-12(p40), IL-12p70, IL-6, and TNFα (p < 0.05) after treatment with IFNγ/LPS across both strains. Collectively, these data suggest that the asocial BTBR mouse strain exhibits a more inflammatory, or M1, macrophage profile in comparison to the social C57 strain. We have further demonstrated a relationship between this relative increase in inflammation and repetitive grooming behavior, which may have relevance to repetitive and stereotyped behavior of autism.
PMCID: PMC3774991  PMID: 24062633
autism; BTBR; behavior; immune system; inflammation; macrophage; M1; M2
5.  Decreased Levels of EGF in Plasma of Children with Autism Spectrum Disorder 
Autism Research and Treatment  2012;2012:205362.
Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder estimated to affect 1 in 110 children in the U.S., yet the pathology of this disorder is not fully understood. Abnormal levels of several growth factors have been demonstrated in adults with ASD, including epidermal growth factor (EGF) and hepatocyte growth factor (HGF). Both of these growth factors serve important roles in neurodevelopment and immune function. In this study, concentrations of EGF and HGF were assessed in the plasma of 49 children with ASD aged 2–4 years old and 31 typically developing controls of a similar age as part of the Autism Phenome Project (APP). Levels of EGF were significantly reduced in the ASD group compared to typically developing controls (P = 0.003). There were no significant differences in HGF levels in young children with ASD and typically developing controls. EGF plays an important role in regulating neural growth, proliferation, differentiation and migration, and reduced levels of this molecule may negatively impact neurodevelopment in young children with ASD.
PMCID: PMC3420731  PMID: 22937258
6.  Differential monocyte responses to TLR ligands in children with autism spectrum disorders 
Brain, behavior, and immunity  2009;24(1):64-71.
Autism spectrum disorders (ASD) are characterized by impairment in social interactions, communication deficits, and restricted repetitive interests and behaviors. Recent evidence has suggested that impairments of innate immunity may play an important role in ASD. To test this hypothesis, we isolated peripheral blood monocytes from 17 children with ASD and 16 age-matched typically developing (TD) controls and stimulated these cell cultures in vitro with distinct toll-like receptors (TLR) ligands: TLR2 (lipoteichoic acid; LTA), TLR3 (poly I:C), TLR4 (lipopolysaccharide; LPS), TLR5 (flagellin) and TLR9 (CpG-B). Supernatants were harvested from the cell cultures and pro-inflammatory cytokine responses for IL-1β, IL-6, IL-8, TNFα, MCP-1, and GM-CSF were determined by multiplex Luminex analysis. After in vitro challenge with TLR ligands, differential cytokine responses were observed in monocyte cultures from children with ASD compared with TD control children. In particular, there was a marked increase in pro-inflammatory IL-1β, IL-6 and TNFα responses following TLR2, and IL-1β response following TLR4 stimulation in monocyte cultures from children with ASD (p<0.04). Conversely, following TLR9 stimulation there was a decrease in IL-1β, IL-6, GM-CSF and TNFα responses in monocyte cell cultures from children with ASD compared with controls (p<0.05). These data indicate that, monocyte cultures from children with ASD are more responsive to signaling via select TLRs. As monocytes are key regulators of the immune response, dysfunction in the response of these cells could result in long-term immune alterations in children with ASD that may lead to the development of adverse neuroimmune interactions and could play a role in the pathophysiology observed in ASD.
PMCID: PMC3014091  PMID: 19666104
monocytes; Toll-Like receptors; autism; ASD; cytokines; inflammation
7.  Decreased cellular IL-23 but not IL-17 production in children with autism spectrum disorders 
Journal of neuroimmunology  2009;216(1-2):126-129.
A potential role for TH17 cells has been suggested in a number of conditions including neurodevelopmental disorders such as autism spectrum disorders (ASD). In the current study, we investigated cellular release of IL-17 and IL-23 following an in-vitro immunological challenge of peripheral blood mononuclear cells (PBMC) from children with ASD compared to age-matched typically developing controls. Following stimulation, the concentration of IL-23, but not IL-17, was significantly reduced (p=0.021) in PBMC from ASD compared to controls. Decreased cellular IL-23 production in ASD warrants further research to determine its role on the generation and survival of TH17 cells, a cell subset important in neuroinflammatory conditions that may include ASD.
PMCID: PMC2981175  PMID: 19800697
Autism spectrum disorders; cytokines; inflammation; IL-17; IL-23; lymphocytes; TH17 cells
8.  Increased IgG4 levels in children with autism disorder 
Brain, behavior, and immunity  2008;23(3):389-395.
Accumulating evidence indicates that immune dysfunction is associated with autism disorders in a significant subset of children. Previous reports have shown abnormal immunoglobulin (Ig) levels, including an increased presence of autoreactive antibodies in the circulation of individuals with autism. As IgG is the predominant antibody isotype in circulation, we expected that an altered immune response could result in an abnormal IgG subclass profile in children with autism. We examined circulating plasma levels of IgG1, IgG2, IgG3, and IgG4 in 241 children from the CHARGE (Childhood Autism Risks from Genetics and the Environment) study, a large epidemiologic case-control investigation, including 114 children who meet full criteria for autism disorder (AU), 96 typically developing control children (TD) from a randomly selected sample of the general population, and 31 children with developmental delays (DD). We report significantly increased levels of the IgG4 subclass in children with AU compared with TD control children (p=0.016) and compared with DD controls (p=0.041). These results may suggest an underlying immunological abnormality in AU subjects resulting in elevated IgG4 production. Further investigation is necessary to elucidate the relationship between immunological findings and behavioral impairments in autism.
PMCID: PMC2696343  PMID: 19136055

Results 1-8 (8)