this effect can be reversed by injecting wild-type T cells but not T cells that do
not express IL-4 (Derecki et al. 2010). Another, nonexclusive, possibility is that
this effect is mediated by myeloid cells. More recently, it has been claimed that
mice deficient in adaptive immunity exhibit social deficits and hyperconnectiv-
ity of fronto-cortical brain regions, that social deficits are reversible via repo-
pulation with lymphocytes, and that interferon-γis a probable molecular link
between meningeal immunity and neural circuits involved in social behavior
(Filiano et al. 2016). Further work is needed to unravel the exact molecular and
cellular mechanisms by which neuroimmune interactions affect cognition, but
data accumulated in the last decade is highly promising and may open up new
important avenues for research.
Figure 5.3(Cont.)Philosophy of Immunology 51