SCIENCE sciencemag.org
NEUROSCIENCE
Learning like a human
The deep network systems
underlying artificial intel-
ligence (AI) reflect a highly
simplified version of our current
understanding of human brain
circuitry and the hierarchy
of cellular connections. This
has allowed the generation of
impressive AI systems, but a
major challenge remains for
human-like learning and percep-
tion. In a Perspective, Ullman
discusses whether more lessons
can be applied from our under-
standing of how the brain works
to improve AI. —GKA
Science, this issue p. 692
CAR T CELLS
The long and short of CAR
activation
Immunological B cell malignan-
cies can be therapeutically
targeted by the adoptive transfer
of T cells that express a chi-
meric antigen receptor (CAR).
Ramello et al. used proteomics
to understand how CARs with
distinct intracellular domains
activated signaling in human
T cells. Independently of specific
signaling domains, the overall
length of CAR intracellular
activation domains determined
whether a CAR promoted strong
T cell signaling. These data may
explain why some CARs can
stimulate antigen-independent
tonic signaling, which leads to
progressive CAR T cell inactiva-
tion. —ERW
Sci. Signal. 12 , eaap9777 (2019).
ASTHMA
Smoothing out muscle
in asthm a
Asthma is often treated with
drugs that reduce airway
inflammation. Saunders et al.
now show that fevipiprant, a
prostaglandin D 2 type 2 receptor
antagonist, reduces smooth
muscle mass in bronchial
biopsies from asthma patients.
Computational simulations of
an asthmatic airway predicted
that decreasing airway smooth
muscle mass was necessary for
the fevipiprant-mediated ame-
lioration of symptoms in asthma
patients observed in a prior
clinical trial. Treating bronchial
biopsies from asthma patients
with fevipiprant in vitro revealed
that the drug-induced decrease
in airway smooth muscle mass
may have been because of
reduced migration of myofibro-
blasts and fibrocytes. —CAC
Sci. Transl. Med. 11 , eaao6451 (2019).MUCOSAL IMMUNOLOGY
Dietary modulation of
T cell immunity
Commensal intestinal bacteria
respond to dietary changes
by modifying gene expres-
sion, leading to shifts in the
amounts of bacterial antigens
encountered by the intestinal
immune system. Wegorzewska
et al. developed a mouse model
system to investigate whether
CD4+ T cell recognition of
antigens of the gut symbiont
Bacteroides thetaiotaomicron is
subject to dietary modulation.
T cell receptor–transgenic T cells
that recognized a bacterial
outer-membrane vesicle protein
differentiated into both regula-
tory and effector T cells, and
colitis emerged after selective
depletion of the regulatory
T cells. Dietary glucose strongly
repressed the T cell–detected
antigen. Thus, dietary modifi-
cations that reduce bacterial
expression of immunodominant
antigens targeted by T cells
could ameliorate some forms
of human inflammatory bowel
disease. —IRW
Sci. Immunol. 4 , eaau9079 (2019).15 FEBRUARY 2019 • VOL 363 ISSUE 6428 705-C
Published by AAAS