Berliner Boersenzeitung - Human brain cells implanted in rats offer research gold mine

EUR -
AED 4.26841
AFN 80.362394
ALL 97.542216
AMD 446.735356
ANG 2.080099
AOA 1065.794205
ARS 1481.767207
AUD 1.776887
AWG 2.092071
AZN 1.980459
BAM 1.954642
BBD 2.348809
BDT 141.226338
BGN 1.956132
BHD 0.43834
BIF 3466.946195
BMD 1.162261
BND 1.493215
BOB 8.038238
BRL 6.486005
BSD 1.163311
BTN 100.147673
BWP 15.618748
BYN 3.807045
BYR 22780.325028
BZD 2.336716
CAD 1.596076
CDF 3354.287055
CHF 0.932981
CLF 0.029194
CLP 1120.296341
CNY 8.342655
CNH 8.346165
COP 4674.330945
CRC 587.052233
CUC 1.162261
CUP 30.799929
CVE 110.199718
CZK 24.634179
DJF 206.947405
DKK 7.463699
DOP 70.258379
DZD 151.514244
EGP 57.439973
ERN 17.433922
ETB 161.636047
FJD 2.620788
FKP 0.864949
GBP 0.86668
GEL 3.150183
GGP 0.864949
GHS 12.127816
GIP 0.864949
GMD 83.106172
GNF 10094.020343
GTQ 8.931709
GYD 243.385819
HKD 9.121487
HNL 30.445964
HRK 7.532663
HTG 152.739518
HUF 398.923459
IDR 18977.696027
ILS 3.908598
IMP 0.864949
INR 100.127437
IQD 1523.897249
IRR 48945.741055
ISK 142.354235
JEP 0.864949
JMD 186.029797
JOD 0.824089
JPY 172.932309
KES 150.300962
KGS 101.640213
KHR 4662.238109
KMF 491.989694
KPW 1046.046309
KRW 1616.942576
KWD 0.355234
KYD 0.969426
KZT 620.152624
LAK 25087.138481
LBP 104232.653
LKR 350.972086
LRD 233.241828
LSL 20.596898
LTL 3.431856
LVL 0.703041
LYD 6.327252
MAD 10.519168
MDL 19.788278
MGA 5176.933206
MKD 61.523554
MMK 2439.678938
MNT 4168.013035
MOP 9.404829
MRU 46.275587
MUR 53.119698
MVR 17.903172
MWK 2017.205016
MXN 21.777182
MYR 4.935007
MZN 74.338683
NAD 20.596898
NGN 1779.387897
NIO 42.814637
NOK 11.838157
NPR 160.236077
NZD 1.94976
OMR 0.446995
PAB 1.163311
PEN 4.140847
PGK 4.817146
PHP 66.377189
PKR 331.310933
PLN 4.244785
PYG 9003.666265
QAR 4.229694
RON 5.072695
RSD 117.080642
RUB 91.375869
RWF 1681.00418
SAR 4.36165
SBD 9.64543
SCR 17.082281
SDG 697.942292
SEK 11.245095
SGD 1.492813
SHP 0.913355
SLE 26.62005
SLL 24372.046713
SOS 664.806172
SRD 43.245469
STD 24056.466061
STN 24.485495
SVC 10.17897
SYP 15112.803405
SZL 20.592801
THB 37.628259
TJS 11.196867
TMT 4.079538
TND 3.419874
TOP 2.722137
TRY 46.947496
TTD 7.897322
TWD 34.181766
TZS 3030.404801
UAH 48.58252
UGX 4168.530579
USD 1.162261
UYU 46.882227
UZS 14725.276806
VES 135.943958
VND 30404.760344
VUV 138.92149
WST 3.080055
XAF 655.568644
XAG 0.030448
XAU 0.000347
XCD 3.14107
XCG 2.096558
XDR 0.815317
XOF 655.568644
XPF 119.331742
YER 280.163552
ZAR 20.586499
ZMK 10461.752209
ZMW 26.785133
ZWL 374.247723
  • CMSC

    0.0900

    22.314

    +0.4%

  • CMSD

    0.0250

    22.285

    +0.11%

  • RBGPF

    0.0000

    69.04

    0%

  • SCS

    0.0400

    10.74

    +0.37%

  • RELX

    0.0300

    53

    +0.06%

  • RIO

    -0.1400

    59.33

    -0.24%

  • GSK

    0.1300

    41.45

    +0.31%

  • NGG

    0.2700

    71.48

    +0.38%

  • BP

    0.1750

    30.4

    +0.58%

  • BTI

    0.7150

    48.215

    +1.48%

  • BCC

    0.7900

    91.02

    +0.87%

  • JRI

    0.0200

    13.13

    +0.15%

  • VOD

    0.0100

    9.85

    +0.1%

  • BCE

    -0.0600

    22.445

    -0.27%

  • RYCEF

    0.1000

    12

    +0.83%

  • AZN

    -0.1200

    73.71

    -0.16%

Advertisement Image
Human brain cells implanted in rats offer research gold mine
Human brain cells implanted in rats offer research gold mine / Photo: Sergiu PASCA - Stanford University/AFP

Human brain cells implanted in rats offer research gold mine

Scientists have successfully implanted and integrated human brain cells into newborn rats, creating a new way to study complex psychiatric disorders such as schizophrenia and autism, and perhaps eventually test treatments.

Advertisement Image

Text size:

Studying how these conditions develop is incredibly difficult -- animals do not experience them like people, and humans cannot simply be opened up for research.

Scientists can assemble small sections of human brain tissue derived from stem cells in petri dishes, and have already done so with more than a dozen brain regions.

But in dishes, "neurons don't grow to the size which a human neuron in an actual human brain would grow", said Sergiu Pasca, the study's lead author and professor of psychiatry and behavioural sciences at Stanford University.

And isolated from a body, they cannot tell us what symptoms a defect will cause.

To overcome those limitations, researchers implanted the groupings of human brain cells, called organoids, into the brains of young rats.

The rats' age was important: human neurons have been implanted into adult rats before, but an animal's brain stops developing at a certain age, limiting how well implanted cells can integrate.

"By transplanting them at these early stages, we found that these organoids can grow relatively large, they become vascularised (receive nutrients) by the rat, and they can cover about a third of a rat's (brain) hemisphere," Pasca said.

- Ethical dilemmas -

To test how well the human neurons integrated with the rat brains and bodies, air was puffed across the animals' whiskers, which prompted electrical activity in the human neurons.

That showed an input connection -- external stimulation of the rat's body was processed by the human tissue in the brain.

The scientists then tested the reverse: could the human neurons send signals back to the rat's body?

They implanted human brain cells altered to respond to blue light, and then trained the rats to expect a "reward" of water from a spout when blue light shone on the neurons via a cable in the animals' skulls.

After two weeks, pulsing the blue light sent the rats scrambling to the spout, according to the research published Wednesday in the journal Nature.

The team has now used the technique to show that organoids developed from patients with Timothy syndrome grow more slowly and display less electrical activity than those from healthy people.

The technique could eventually be used to test new drugs, according to J. Gray Camp of the Roche Institute for Translational Bioengineering, and Barbara Treutlein of ETH Zurich.

It "takes our ability to study human brain development, evolution and disease into uncharted territory", the pair, who were not involved in the study, wrote in a review commissioned by Nature.

The method raises potentially uncomfortable questions -- how much human brain tissue can be implanted into a rat before the animal's nature is changed? Would the method be ethical in primates?

Pasca argued that limitations on how deeply human neurons integrate with the rat brain provide "natural barriers".

Rat brains develop much faster than human ones, "so there's only so much that the rat cortex can integrate".

But in species closer to humans, those barriers might no longer exist, and Pasca said he would not support using the technique in primates for now.

He argued though that there is a "moral imperative" to find ways to better study and treat psychiatric disorders.

"Certainly the more human these models are becoming, the more uncomfortable we feel," he said.

But "human psychiatric disorders are to a large extent uniquely human. So we're going to have to think very carefully... how far we want to go with some of these models moving forward."

(T.Renner--BBZ)

Advertisement Image