Immunomodulatory effects of platelets on the severity of hand, foot, and mouth disease infected with enterovirus 71

Figures

• 

  Fig. 1. The levels of platelet parameters and platelet-associated inflammatory index parameters in mild HFMD (n = 23), severe HFMD (n = 30), and healthy controls (n = 27). a The levels of platelet parameters PLT, PCT, MPV, PDW, and P-LCR were analyzed in mild HFMD, severe HFMD, and healthy controls. b The levels of platelets/lymphocytes, platelets/neutrophils, platelets/monocytes, platelets/eosinophils, and platelets/basophils were analyzed in healthy controls, mild HFMD, and severe HFMD. c The levels of platelets/T cells, platelets/CD4+ T cells, platelets/CD8+ T cells, platelets/NK cells, and platelets/B cells were detected in the CFS of mild HFMD, and severe HFMD. Statistical significance was analyzed by Student’s t test and one-way ANOVA. *p < 0.05, **p < 0.01, and ***p < 0.001; error bars show the standard deviation. PLT: platelet count; MPV: mean platelet volume; PCT: plateletocrit; PDW: platelet distribution width; P-LCR: platelet large cell ratio (P-LCR).

• 

  Fig. 2. The levels of Th1 and Th2 as well as their associated key transcription factors and effector cytokines in mild HFMD (n = 23), severe HFMD (n = 30), and healthy controls (n = 27). a The Th1 and Th2 subpopulations were detected by flow cytometry as indicated with representative examples from mild HFMD, severe HFMD, and healthy controls using the protocol described in the “Methods” section. b The total frequencies of circulating Th1 and Th2 were analyzed in healthy controls, mild HFMD, and severe HFMD. c–e The frequencies and absolute numbers of Th1, Th2, and Th1/Th2 were detected in healthy controls, mild HFMD, and severe HFMD. f The levels of T-bet and GATA-3 in healthy controls, mild HFMD, and severe HFMD. g The levels of IFN-γ and IL-4 in healthy controls, mild HFMD, and severe HFMD. Statistical significance was analyzed by Student’s t test and one-way ANOVA. *p < 0.05, **p < 0.01, and ***p < 0.001; error bars show the standard deviation.

• 

  Fig. 3. Relationship between PLT and CD4+ T cell subset or its associated key transcription factors. a The correlations between the levels of PLT and Th1/Th2 ratio are shown in mild and severe patients. b The correlation between the levels of PLT and the frequency of Th1 or Th2 is shown in severe patients. c The correlation between the levels of PLT and T-bet or GATA-3 is shown in severe patients. d The correlation between the level of PLT and IFN-γ or IL-4 is shown in severe patients. Statistical significance was analyzed by Student’s t test and one-way ANOVA. *p < 0.05, **p < 0.01, and ***p < 0.001; error bars show the standard deviation. Lines indicate linear regression. Spearman’s rank correlation coefficients (R2) and the corresponding p values are indicated. PLT: platelet count.

• 

  Fig. 4. In the case of different naive CD4+ T:platelets (T/P), the platelets of mild, healthy, and severe children with naive CD4+ T cells of healthy children were incubated in vitro for 3 days. a–c The level of Th1 was detected by FACS, the levels of IFN-γ were detected by ELISA, and the level of T-bet mRNA relative expression was detected by qPCR. d–f The level of Th2 was detected by FACS, the levels of IL-4 were detected by ELISA, and the level of GATA-3 mRNA relative expression was detected by qPCR. g–i The level of Th17 was detected by FACS, the levels of IL-17A were detected by ELISA, and the level of RORγt mRNA relative expression was detected by qPCR. Statistical significance was analyzed by Student’s t test and one-way ANOVA. *p < 0.05, **p < 0.01, and ***p < 0.001; error bars show the standard deviation.

• 

  Fig. 5. Under the condition of different naive CD4+ T:platelets (T/P), platelets and naive CD4+ T cells were incubated in vitro for 3 days. a The level of CD40 mRNA relative expression is shown in healthy, mild, and severe patients. b The level of Mac-1 mRNA relative expression is shown in healthy, mild, and severe patients. c The level of PSGL-1 mRNA relative expression is shown in healthy, mild, and severe patients. Statistical significance was analyzed by Student’s t test and one-way ANOVA. *p < 0.05, **p < 0.01, and ***p < 0.001; error bars show the standard deviation.