Medycyna Wet. 66 (9), 588-592, 2010
Kowalczyk A., Markowska-Daniel I.
Immune response during infection caused by influenza virus
The paper reviews literature on the immunological response to influenza virus (IV) infection. The first part of the paper focuses on humoral response involving antibodies against IV and proinflamatory cytokines. The response involves mainly antibodies of IgA, IgG and IgM classes, produced against antigenic proteins of IV - hemagglutinin and neuraminidase. The antibodies are presented in blood and in BALB from 7 DPI and remain at a high level for 8-10 weeks post infection. Moreover, cytotoxic T lymphocytes are more specific to NP and M proteins. Virus titres in the lungs are tightly correlated with the level of IFN-α, TNF-α, IL-4, IL-6, IL-10 and IL-12 in BALF. There is no correlation between virus replication and cytokines in serum. The biological effects of immunosuppressive activity caused by IV are discussed in the second part of this review. Some of IV strains posses NS protein in the form known as IFN-inducing particles (IFP), some others in the form of INF-suppressing particles (ISP). IL-10 activity of the host was also described as an immunosuppressive factor. The third part of the paper summarizes the relationship between the pathogenesis of influenza and the acute phase proteins induced by cytokines. To recapitulate, immunological response to infection caused by influenza virus is a multistage and multifactor process, including specific and unspecific humoral and cell response. The response involves mainly proinflammatory cytokines and acute phase proteins. Undoubtedly, biological properties of IV, especially its suppressive effect on the secretion of INF along with IL-10 activity, reduce cell response, influencing the defense of the organism against infection. This model of influenza virus infection may be valuable for assessing the therapeutic potential of cytokine antagonists.
Keywords: influenza virus, immune response, pathogenesis, cytokines, acute phase proteins