Clinical Characteristics Of Severe Influenza In Pregnant Women In Beijing Area And Non-specific Immunity Represented By NK Cells

Objective It is necessary to analyze the clinical characteristics of patients with severe influenza,and explore the critical risk factors of influenza by observing the function and state of Natural Killer cells in the peripheral blood of influenza and combining with Clinical development process,so as to provide a practical basis for better treatment of influenza.Method Part 1:Retrospective study was used to analyze the clinical characteristics and prognosis of the special population(pregnant women)infected with influenza and the influence of influenza virus on pregnant women and fetus.Part 2:(1)A total of 202 healthy volunteers aged 18 to 90 years,166 patients with severe influenza and a special population infected with influenza(pregnant women)were recruited as research subjects.Secondly.The peripheral venous blood samples of influenza patients were mainly selected at the first diagnosis period.(2)Phenotypic staining and functional evaluation were performed by multi-color flow cytometry.Phenotypic staining included surface receptors(CD158,NKG2A,etc.),activation(CD69),and functional evaluation included proliferation(Ki-67)and killing ability(Granzyme and perforin).(3)the role of natural killer cells in patients with severe influenza was clarified and the relationship between natural killer cells and the disease progression of influenza patients was evaluated.Result1.Higher rates of ICU admission with the second and third trimesters.However,in the absence of early antiviral therapy,treatment within 2 days and within 3-4 days was associated with milder disease progression in hospitalized women of all trimester.And And there may be some benefit to starting treatment even four days after symptoms appear.2.Old age may be a risk factor for the prognosis of hospitalized pregnant patients with influenza.3.Duration of disease within three days within antiviral therapy can shorten the length of hospital stay in pregnant and maternal patients with influenza.4.There was no difference in the absolute number of NK cells in the peripheral blood among young,middle-aged and old people.The number of CD56bri 16-NK cells in the elderly group was significantly lower than that in the middle-aged group(P=0.001).With the increase of age,the absolute number of CD56-CD16+NK cells increased,and the number of cells in the elderly group was significantly higher than the young group(P=0.001).5.Compared with healthy volunteers,the absolute number of NK cells in the peripheral blood of patients with severe influenza decreased significantly.The total number of CD3+cells in the peripheral blood of patients with severe influenza also decreased significantly.6.The proliferation and activation capacity of total NK cells were significantly increased in patients with severe influenza(P<0.001).7.The activation and proliferation of CD56bri 16-NK cells in patients with severe influenza were significantly increased,and Granzyme and perforin were also significantly increased(P=0.0001).Conclusion1.As a influencing factor,Age affects the function and status of NK cells.2.Natural killer cells play an important role in severe influenza infection,especially in the early stage of infection.3.The treatment of antiviral drugs affects the function of natural killer cells to some extent,and the positive or negative effects of antiviral drugs should be further explored.