WASHINGTON — A novel immune cell may offer an important new clue to why malaria kills some people and not others.
Australian researchers discovered a specialized cell crowding the bloodstream of severe malaria sufferers but not the less sick.
Now the question: Is that cell responsible for worsening malaria or a consequence of having a severe case?
The research, by Monash University immunologists in Australia, is reported today in the journal PLoS Pathogens.
The World Health Organization said many drugs have lost their effectiveness against the parasite and there is no vaccine.
Scientists hunting better protections are focusing on a big mystery of why infected people in the same villages can have radically different outcomes.
The major clue until now: People with gene mutations that can cause sickle cell disease or similar blood disorders also have some protection against severe malaria.
Today’s report brings another clue.
The immune system harbors numerous types of cells that have different jobs. So-called regulatory T cells are thought to help keep the system in balance by tamping down overactive immune responses from other cells.
Monash University researchers tested 33 malaria-infected adults in Papua, Indonesia, half of whom were severely ill.
Both sets of patients harbored similar numbers of T-regs. But in the severe patients, many of those cells had changed to become extrasuppressive, thanks to a new and distinct receptor that formed on the cells’ surface, reported immunologist Magdalena Plebanski, the lead researcher.
"Our results indicate that severe malaria is accompanied by the induction of highly suppressive ... cells that can promote parasite growth,” Plebanski concluded. She urged that vaccine studies carefully examine whether recipients form this type of immune reaction.
by the associated press
Australian researchers discovered a specialized cell crowding the bloodstream of severe malaria sufferers but not the less sick.
Now the question: Is that cell responsible for worsening malaria or a consequence of having a severe case?
The research, by Monash University immunologists in Australia, is reported today in the journal PLoS Pathogens.
The World Health Organization said many drugs have lost their effectiveness against the parasite and there is no vaccine.
Scientists hunting better protections are focusing on a big mystery of why infected people in the same villages can have radically different outcomes.
The major clue until now: People with gene mutations that can cause sickle cell disease or similar blood disorders also have some protection against severe malaria.
Today’s report brings another clue.
The immune system harbors numerous types of cells that have different jobs. So-called regulatory T cells are thought to help keep the system in balance by tamping down overactive immune responses from other cells.
Monash University researchers tested 33 malaria-infected adults in Papua, Indonesia, half of whom were severely ill.
Both sets of patients harbored similar numbers of T-regs. But in the severe patients, many of those cells had changed to become extrasuppressive, thanks to a new and distinct receptor that formed on the cells’ surface, reported immunologist Magdalena Plebanski, the lead researcher.
"Our results indicate that severe malaria is accompanied by the induction of highly suppressive ... cells that can promote parasite growth,” Plebanski concluded. She urged that vaccine studies carefully examine whether recipients form this type of immune reaction.
by the associated press
