Sordillo L M, Nickerson S C
Proc Soc Exp Biol Med. 1986 Sep;182(4):522-30. doi: 10.3181/00379727-182-42375.
Mice were used as models for bovine mastitis in an attempt to modify the susceptibility of mammary glands to Streptococcus uberis infection. Murine mammary glands were injected with pokeweed mitogen (PWM) prior to experimental bacterial challenge to accelerate involution and enhance antimicrobial mechanisms. PWM injection reduced the numbers of streptococci recovered when compared to controls. Histological examination of tissues from PWM-treated mice revealed a reduction in secretory activity and advanced involution. PWM-treated tissues had considerably more leukocytes infiltrating the epithelium, lumen, and underlying connective tissue. Bacteria were observed within the epithelium and alveolar lumen and internalized within neutrophils and macrophages in both PWM-injected and control tissue. Results of this study suggest PWM injection provided some protection against S. uberis mastitis by accelerating mammary involution, enhancing antimicrobial defenses, and facilitating a marked cellular response prior to bacterial challenge.
小鼠被用作牛乳腺炎的模型，以试图改变乳腺对乳房链球菌感染的易感性。在实验性细菌攻击之前，向小鼠乳腺注射商陆有丝分裂原（PWM），以加速退化并增强抗菌机制。与对照组相比，PWM注射减少了回收的链球菌数量。对PWM处理小鼠的组织进行组织学检查发现，分泌活动减少且退化进程加快。PWM处理的组织有更多的白细胞浸润上皮、管腔和下方的结缔组织。在PWM注射组和对照组组织的上皮、肺泡腔以及中性粒细胞和巨噬细胞内均观察到细菌。这项研究的结果表明，PWM注射通过加速乳腺退化、增强抗菌防御以及在细菌攻击之前促进明显的细胞反应，为乳房链球菌性乳腺炎提供了一定的保护作用。
