The Week India - July 29, 2018

COVER STORY

32 THE WEEK · JULY 29, 2018

HEALTH

C

ancer vaccines are

back in the headlines

with research teams

from Stanford Uni-

versity School of Medicine pub-

lishing breakthrough results of

immunotherapy studies. Cancer

research seems to be experienc-

ing a tidal wave of immuno-

therapy treatment options; the

excitement around the US Food

and Drug Administration ap-

proval of the fi rst CAR T-cell

therapy and then a second one

within months, is still afresh.

The Stanford teams are taking

this to a new level by pressing

all the right buttons for a cancer

vaccine.

This February, an interest-

ing study led by researchers

at the university has shown

experimental vaccines as pos-

sible treatments for cancers in

mice, and the university is start-

ing human trials soon.

Stimulating immune system

against solid tumours

The study injected minute

amounts of two immune-stim-

ulating agents directly into solid

Taking it to

the next level

Human trials will soon begin for a cancer vaccine

developed by Stanford researchers

BY PRIYA MENON to attack the tumour. However,

as the tumour grows, it devises

ways to suppress this activity of

the T-cells.

The new method reactivates T-

cells and harnesses a much stron-

ger immune response against

the tumour. It uses a combina-

tion of two molecules; the fi rst

is a short piece of DNA or the

CpG oligonucleotide causing

the T-cells to increase expression

of receptor molecules, OX40,

and the other is an antibody that

binds with the OX40, which

activates the T-cells to amplify

the anti-cancer response. Dr

Idit Sagiv-Barfi , the lead author

of the study, explains, “We use

a combination of two reagents.

The fi rst, CpG, is a small DNA

sequence that has properties of

microbial/bacterial DNA un-

like human DNA. When it is in-

jected into the tumour, immune

cells in the tumour sense it as

foreign DNA and begin a sig-

naling cascade eventually lead-

ing to a local immune response.

T-cells are among the cells that

are activated, as a result of this

activation they increase the ex-

pression of a protein known

as OX40 on their surface. The

DR IDIT SAGIV-BARFI

tumours in mice and found that

this could eliminate all traces of

cancer in the animals, including

distant, untreated metastases.

“When we use these two

agents together, we see the elim-

ination of tumours all over the

body,” said Ronald Levy, MD,

professor of oncology and se-

nior author of the study, in the

Stanford press release.

The cancer environment dis-

plays a strange kind of relation-

ship with the immune system.

Immune cells like T-cells rec-

ognise the abnormal proteins

present on the surface of can-

cer cells and infi ltrate the cells