Neutrophil and Macrophage Percentages in BLB constructs. (A) Percentage neutrophils in BLB constructs at 3 days (n=3), 7 days (n=4), 14 days (n=3), 28 days (n=4), and acellularized group (n=3) compared to native ACL ligament (n=4). Neutrophil percentage at the 3-day time point is significantly higher than native ACL levels. Quantification of neutrophil staining showed an average 0.08 ± 0.09% of neutrophils within native ACL, 10.85 ±2.50% of neutrophils within the construct at 3 days, 0.46 ± 0.62% at 7 days, 0.46 ± 0.62% at 14 days, 0.17 ± 0.21% at 28 days, and 0.36 ± 0.40% in the acellularized group.(*) indicates significance compared to the native ACL control. (**) indicates significance compared to the 3-day time point. (B) Total macrophage percentage, marked by CD68, in BLB construct at 3 days (n=4), 7 days (n=4), 14 days (n=3), 28 days (n=4), and in the acellularized group (n=3) compared to native ACL (n=4). Total M2 macrophage percentage, marked by CD163, in BLB construct at 3 days (n=4), 7 days (n=3), 14 days (n=4), 28 days (n=4), and acellularized group (n=3) compared to native ACL (n=3). The average percentage of all macrophages (CD68) in the BLB construct was 7.40 ± 6.26% for the 3-day time point, 11.00 ± 4.39% in the 7-day time point, 8.15 ± 3.95% in the 14-day time point, 10.66 ± 2.30% in the 28-day time point, and 8.46 ± 2.40% for the acellularized group. For the total macrophage data (CD68), * indicates significance compared to the native ACL control. The average percent of M2 macrophage (CD163) in native ACL ligament is 0.01 ± 0.002%. The average percent of M2 macrophages (CD163) in the BLB construct was 3.00 ± 1.65% for the 3-day time point, 6.69 ± 3.99% for the 7-day time point, 3.00 ± 1.65% in the 14-day time point, 7.22± 1.39% for the 28-day time point, and 4.55 ± 0.86% for the acellularized group. For the M2 macrophage data (CD163), # indicates significance compared to the native ACL control. Total macrophage percentage was significantly higher at the 7-day time point. M2 macrophage percentage was significantly higher at both the 7-day and 28-day time points when compared to native ACL (p<0.05).