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Advanced Neurology Role of immunosuppressants in autism

2.2. Immune response Children with ASD have elevated rates of autoimmunity

The potential significance of immunological dysregulation and immune system abnormalities, and they have a family
and autoimmune disease in ASD has received more history of autoimmune disorder, which increases the risk
of ASD by 28%, psoriasis by 59%, rheumatoid arthritis by
attention from researchers. The immune system of autistic
children has been profoundly altered, both cellularly 51%, Type 1 diabetes by 49%, and hypothyroidism by 64%,
and systemically. Multiple genetic studies point to a link which are the disorders with the highest relative risks.
between the immune system and autism. According to In ASD, the cerebral spinal fluid-brain barrier is disrupted
the results of these investigations, abnormal immune at specific foci due to dysregulated cellular immunity [58,59] .
responses are associated with autism and may be a potential When maternal autoimmunity is active during pregnancy,
therapeutic target for the disorder. Croen et al. also found the risk of ASD in offspring is significantly increased,
an increased prevalence of immune-mediated disorders, indicating that an active inflammatory state during
such as psoriasis and Type 1 diabetes, in mothers of infants gestation may negatively influence the fetal neurological
diagnosed with ASD. Both of these hypotheses suggest that trajectory. The immune systems of most fetuses are altered
autoimmune reactions and immunological malfunction as a result of the mother’s exposure to at least one virus
during pregnancy may lead to a later diagnosis of ASD while pregnant. There is a correlation between the severity
in the offspring [12,14,15] . The maternal immune activation of the infection, the intensity of the inflammatory response
(MIA) model has demonstrated consistent findings, (and the fever), and the risk of ASD in the developing
helping to establish a subtype of autism that is supported child. Cytokines in the mother’s blood, such as interleukin
by observations of autism-relevant abnormal behaviors, (IL)-6 and IL-17, are produced in response to infections
providing some of the strongest support for maternal and, depending on the embryonic or fetal developmental
infection as a contributor to autism. By directly infecting stage, can cross the placenta to stimulate the production
pregnant rodents (with viruses like influenza, or E. coli) of other detrimental immune mediators that damage
or by administering a double stranded RNA; mimic like the fetal brain [18,60-62] . Immune abnormalities have been
poly(I: C), the MIA model causes profound changes in consistently observed in autistic children, suggesting
the offspring’s immunological, neurodevelopmental, a dysregulated immune response in this population.
and behavioral profiles [52-56] . The human influenza virus These include abnormal or skewed T helper cell type 1
was used to infect two strains of pregnant mice, and the (TH1) and T helper 2 (TH2) cytokine profiles, decreased
resulting progeny had aberrant behavior, exploratory lymphocyte numbers, decreased T cell mitogen responses,
behavior, and social interaction possibly suggesting and the imbalance of serum immunoglobulin levels.
[56]
that the immunological response of the mother, rather Autoimmunity and a relationship with immune-based
than the sickness itself, was responsible for the effects genes like HLA-DRB1 and complement C4 alleles have also
of prenatal exposure to an infectious agent, following been suggested as potential causes of autism. There is an
the administration of either a single dose of influenza evidence that immune cells and immunological chemicals,
on embryonic day E9.5 or poly(I: C) on embryonic day such as cytokines and chemokines, might influence brain
E12.5. The offspring from both groups revealed cerebellar activity. Modulation of systemic and central nervous system
development anomalies comparable to those reported in (CNS) responses to infection, injury, and inflammation
[56]
autistic children . The male progeny of MIA showed a are just a few examples of how immune cells and immune
variety of abnormalities that are consistent with autism chemicals like cytokines and chemokines can influence
when they were tested in equipment consisting of three brain function. Pro-inflammatory cytokines such as
chambers. For instance, they spent a greater amount of IL-1, IL-6, IL-12, interferon (IFN)-gamma, and tumor
time in the non-social item and a smaller amount of time necrosis factor (TNF)-alpha have been found to have
with the social item, which is indicative of a decreased pleiotropic effects in the CNS, with a growing involvement
degree of sociability . in neurodevelopment [4,63,64] . This information suggests a
[51]
link between the immune system and autism, which can
Researchers have found that certain patterns of be explored further to develop more effective therapies for
immunoglobulin production are associated with autism. the disorder.
Some believe that intravenous immunoglobulin therapy
is useful because it prevents the generation of endogenous 3. Role of caspase and NK cells in autism
autoantibodies and lessens the activation of aberrant
antibody production by T cells in B cells. It has been seen 3.1. Caspase
that children who got treatment showed considerable Evidence suggests that caspases, a family of cysteine
improvements in their total IgG, IgM, or low IgA levels . proteases involved in programmed cell death, may play
[57]

Volume 2 Issue 2 (2023) 6 https://doi.org/10.36922/an.391