CASP1 and lymphopenia: Lastly, in the entire 50 patient cohort there was a significant, albeit weak association between the MV caspase-1 activity and lymphopenia as measured by absolute lymphocyte count on day of enrollment R2 = 0.09 (p = 0.03) and day 3 of ICU stay R2 = 0.12 (p = 0.04) (Figure 3B&3C).