Journal ArticleDOI
A new function for platelets: IgE-dependent killing of schistosomes.
Reads0
Chats0
TLDR
The experiments reported here show that platelets, taken from rats after specific periods of infection with S. mansoni, were able to kill schistosomula, and that normal human or rat platelets acquired toxic properties towards the same target in the presence of serum from infected individuals.Abstract:
Several killing mechanisms against schistosomes have been described in vitro, involving cellular and humoral factors. Neutrophils, eosinophils—with an accessory role for mast cells—monocytes and macrophages have been shown to exhibit cytotoxic properties against Schistosoma mansoni larvae, in association with antibodies of various isotypes or with complement (reviewed in ref. 1). Lymphocyte participation in effector functions is mediated mainly through lymphokines inducing cytotoxic macrophages2, and, in certain cases, directly by T cells3. The experiments reported here show that platelets, taken from rats after specific periods of infection with S. mansoni, were able to kill schistosomula, and that normal human or rat platelets acquired toxic properties towards the same target in the presence of serum from infected individuals. The humoral factor involved in this process was shown to be IgE, and evidence was obtained of a Fc receptor for IgE on human and rat platelets. The passive transfer of immune platelets to normal rats conferred a high degree of protection towards a challenge infection by the parasite.read more
Citations
More filters
Journal ArticleDOI
Immunological modulation and evasion by helminth parasites in human populations
TL;DR: New techniques are starting to expose the diverse mechanisms by which these agents modulate or evade their hosts' defences, creating a dynamic interaction between the human immune system and the parasite population.
Journal ArticleDOI
Platelets roll on stimulated endothelium in vivo: an interaction mediated by endothelial P-selectin
TL;DR: An interesting parallel between platelets and leukocytes is observed in that both of these blood cell types roll on stimulated vessel wall and that this process is dependent on the expression of endothelial P-selectin.
Journal ArticleDOI
New concepts in the pathogenesis of bronchial hyperresponsiveness and asthma
TL;DR: PAF antagonists will reveal whether PAF plays an important role in the eosinophilic inflammation of asthma, which may lead to epithelial damage, a key feature of asthmatic airways.
Journal ArticleDOI
Role of blood platelets in infection and inflammation.
TL;DR: Blood platelets are here presented as active players in antimicrobial host defense and the induction of inflammation and tissue repair in addition to their participation in hemostasis.
References
More filters
Journal ArticleDOI
Release of serotonin from human platelets induced by aggregated immunoglobulins of different classes and subclasses
TL;DR: The ability of human myeloma proteins of different classes and subclasses and of macroglobulins to aggregate washed human platelets and release serotonin from the platelets was investigated and compared with the activity of normal IgG and tetanus-antitetanus IgG antigen-antibody complexes.
Journal ArticleDOI
Effector mechanisms of immunity to schistosomes and their regulation.
TL;DR: Rat infection by schistosomes deserves particular mention, as this rodent experimental infection by cercariae results in the establishment of a worm population which is almost entirely rejected 3 to 4 weeks after the initial challenge, this rejection being itself followed by a strong and prolonged immunity to reinfection.
Journal Article
In vitro killing of S. mansoni schistosomula by lymphokine-activated mouse macrophages.
TL;DR: Among the immune mechanisms that participate in immunity to reinfection, cell-mediated immunity that involves inflammatory macrophages should no longer be restricted to microorganisms and protozoans and could be extended to multicellular parasites like schistosomes.
Journal ArticleDOI
Destruction of the multicellular parasite Schistosoma mansoni by T lymphocytes.
TL;DR: These studies show that T lymphocytes activated by a variety of stimuli develop the capacity to kill schistosomula of Schistoma mansoni, and direct killing of infectious agents by cytotoxic T cells may contribute to host resistance to infections.
Journal ArticleDOI
Lysis of antibody-coated cells by platelets.
TL;DR: The significance of the lytic reaction described here is not known but may lie in antibody mediated release of microbicidal substances from platelets.