S. Pichyangkul et al., PLASMODIUM-FALCIPARUM PIGMENT INDUCES MONOCYTES TO RELEASE HIGH-LEVELS OF TUMOR-NECROSIS-FACTOR-ALPHA AND INTERLEUKIN-1-BETA, The American journal of tropical medicine and hygiene, 51(4), 1994, pp. 430-435
Citations number
21
Categorie Soggetti
Public, Environmental & Occupation Heath","Tropical Medicine
We show that high levels of tumor necrosis factor-alpha (TNF-alpha) ac
tivity were consistently detected when monocytes were cocultured with
Plasmodium falciparum schizont stage-parasitized erythrocytes that sub
sequently ruptured. Isolated pigment recovered from ruptured schizonts
was found to specifically induce monocyte release of high levels of T
NF-alpha and interleukin-1 beta (IL-1 beta). Particulate free-culture
supernatant that contained various soluble parasite macromolecules ind
uced relatively low levels of TNF-alpha and IL-1 beta. When isolated p
igment was treated with protease, the monokine inducing-activity was a
bolished. Isolated pigment prepared from different natural isolates of
P. falciparum stimulated variable levels of monokine production. We p
ropose that in vivo, malaria pigment from parasites sequestered in the
host microvasculature is a physiologically relevant moiety that inter
acts with monocytes and stimulates the release of TNF-alpha and IL-1 b
eta. These observations suggest that malaria pigment may be a virulenc
e factor in the monokine-mediated induction of organ-specific and syst
emic pathophysiology in falciparum malaria.