SIRS/sepsis induces lymphopenia.

SIRS induced by LPS or CpG causes marked, protracted leukopenia, whilst septic peritonitis does not. (A) SIRS or septic peritonitis was induced in mice as described. 10 or 30 days later, white blood counts or (B) lymphocyte numbers in the periphery were determined by automated haemocytometry. Data are presented as mean + SEM including at least 13 animals per experimental group. A One-way ANOVA with post-hoc Bonferroni analysis was performed to determine significances (***p≤0.001). (C) Total T-lymphocyte counts from spleen and (D) CD4⁺ to CD8⁺ T-cell ratio in spleen determined in single cell preparations by flow cytometry. Data are presented as mean + SEM and include at least 9 animals per experimental group. A One-way ANOVA with post-hoc Bonferroni analysis was performed to determine significances (* p≤0.05, ** p≤0.01, ***p≤0.001). PBL: peripheral blood lymphocytes.