Figure 2.

Quantitative morphometric analysis of terminal deoxynucleotidyl transferase (TdT) immunostaining in thymus from preterm baboons given O₂ PRN ± 2A11. (a–b) TdT-immunostained sections of thymus from 125-d/PRN animals. Scale bar in lower left corner = 50 μm. Arrowheads indicate thymic cortex (capsule). (a) BPD control 125-d/PRN × 21-d animal, no intervention (n = 3). (b) Image shows 125-d/PRN × 21 d treated with 2A11 (n = 5). (c and d) Quantitative morphometric analysis of 14-d/PRN and 21-d/PRN animals for numbers of TdT⁺ nuclei per total area of the thymic cortex tissue section in square inches. Similar results were obtained when numbers of TdT⁺ cells were normalized for the area of the cortex plus medulla. (c) Groups tested were: 125-d/PRN × 14-d animal, no intervention (n = 5); 125-d/PRN × 14 d + MOPC21 (n = 5); 125-d/PRN × 14 d + 2A11 (n = 3); and the 21-d animals listed in a and b above. *p < 0.0001 compared with 125-d/PRN × 14 d without intervention; ^†p < 0.04 compared with 125-d/PRN × 14 d + MOPC21; **p < 0.0002 compared with 125-d/PRN × 21 d with no intervention. (D) GCs for numbers of TdT⁺ nuclei/in² of thymic cortex: 125 d (n = 4); 140 d (n = 5); 175 d (n = 3); and full-term natural delivery (n = 3). *p < 0.02 and ^†p < 0.01 compared with 125-d GC group. M = medulla.