it do not attack platelets it increases the porosity of arteries and veins due to which platelets being smaller in size recedes out of the blood and the remaining blood seems devoid of platelets
No, As far as recent literature is concerned, Dengue virus attacks platelets and other immune cells, Platelets are used by DENV to replicate and increase progenies, Check the recent study published in Blood (link below). There develop autoantibodies against antigens shared by virus and platelets, and thus platelets get destructed by autoimmunity resulting in thrombocytopenia. Although, there are other mechanism also, like decrease in platelet production in bone marrow in dengue fever. Research is going on to highlight more details.
http://www.bloodjournal.org/content/126/3/378?sso-checked=true
Dr Himmat, i believe platelets do not cross out of arterial or venous spaces, its not about their size, its about the function.
As a probable initiating event, direct purified DENV-platelet binding was followed in the current study by quantitative reverse transcription-polymerase chain reaction and confirmed antigenically. There develop autoantibodies against antigens shared by virus and platelets, and thus platelets get destructed
by autoimmunity resulting in thrombocytopenia. Although, there are other mechanism also, like decrease in platelet production in bone marrow in dengue fever. Research is going on to highlight more details.
Why does Dengue virus attack platelets? - ResearchGate. Available from: https://www.researchgate.net/post/Why_does_Dengue_virus_attack_platelets [accessed Aug 11, 2016].
The answered is a little bit more complicated, that what has been portrayed here. Changes in platelets in dengue and in another infections results of a combination of factors. First, it needs to be clarified that now platelets are recognized as distant members of the immune system, and bind and engulf to pathogens including bacteria and viruses. Platelets have a vast variety of receptors that facilitate that they bind to various pathogens. So if we can make a parenthesis, the correct question is why the platelets attack so many pathogens.
Changes in platelets result from different scenarios: in some cases once they engulfed the pathogen the immune cells destroy them. In other cases, a cross-reactivity reaction occurred and they are destroyed. Notably, in many cases, platelets destroyed the virus and as a result of this activation path, apoptosis is triggered.
In the third case, the virus uses platelets as trojan horses to avoid the immune response. In this case, there is no response and platelets survive until a signal is triggered (i.e. initial replication)
In other cases viral replication takes place and platelets are destroyed when the viruses are budding. What triggers these distinct types of immune responses is unknown.
Finally, many of these viruses affect bone marrow and megakaryocytes resulting in a diminished production of platelets
To add to the above, there is another reason, dengue IgM can destroy platelets with complement. Article Generation of IgM anti-platelet autoantibody in dengue patients
Bruce
Dengue virus does not attack the blood platelets. The latter are destroyed due to autoimmune reaction induced as a result of infection by dengue virus.
The reasons for low platelet count in dengue fever are as follows.
- Dengue virus, the main cause of dengue fever induces bone marrow suppression. Since bone marrow is the manufacturing centre of blood cells its suppression causes deficiency of blood cells leading to low platelet count. Anaemia and spontaneous severe bleeding are the other resultant factors of bone marrow suppression.
- Studies suggest that dengue virus can even bind to platelets of human blood in the presence of virus-specific antibody
- https://www.onlymyhealth.com/cause-low-platelet-count-in-dengue-fever-1301653922
Dengue virus may lead to thrombocytopenia either via direct bone marrow suppression or by means of raising antibodies to destroy platelets in the peripheral circulation.
kindly see the attached article.
- Badges
- Science topic
- Similar topics
- Geoscience
- Asia
- India