GENERAL ANATOMY
IMMUNE SYSTEM
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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interferon
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complement
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antibody
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thymus
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Detailed explanation-1: -Interferon is secreted by cells in response to stimulation by a virus or other foreign substance, but it does not directly inhibit the virus’s multiplication. Rather, it stimulates the infected cells and those nearby to produce proteins that prevent the virus from replicating within them.
Detailed explanation-2: -Type I interferon (IFN-alpha and IFN-beta) is secreted by virus-infected cells while type II, immune or gamma interferon (IFN-gamma) is mainly secreted by T cells, natural killer (NK) cells and macrophages.
Detailed explanation-3: -Interferons (type I to III) are critical immune-ecological components produced by virus-infected cells; they function as antiviral molecules and immune-modulators.
Detailed explanation-4: -In infected organs, IFN-I is produced by parenchymal cells, fibroblasts, tissue resident macrophages and DCs. In draining lymph nodes, subcapsular sinus macrophages have a major role in the secretion of IFN-I and restriction of viral spread.
Detailed explanation-5: -Interferons (IFNs)-the body’s first line of antiviral defence-are cytokines that are secreted by host cells in response to virus infection. By inducing the expression of hundreds of IFN-stimulated genes, several of which have antiviral functions, IFNs block virus replication at many levels.