Conlan J W, North R J
Trudeau Institute, Inc., Saranac Lake, New York 12983.
J Exp Med. 1994 Jan 1;179(1):259-68. doi: 10.1084/jem.179.1.259.
This study shows that in mice selectively depleted of neutrophils by treatment with a monoclonal antibody, RB6-8C5, listeriosis is severely exacerbated in the liver, but not in the spleen or peritoneal cavity during the crucial first day of infection. At sites of infection in the livers of neutrophil-depleted mice, Listeria monocytogenes grew to large numbers inside hepatocytes. By contrast, in the livers of normal mice neutrophils rapidly accumulated at infectious foci and this was associated with the lysis of infected hepatocytes that served to abort infection in these permissive cells. In the spleen the situation was different, in that depletion of neutrophils did not result in appreciable exacerbation of infection. In this organ intact infected cells, many of which appeared to be fibroblast-like stromal cells, were found at foci of infection in the presence or absence of large numbers of neutrophils. This suggests that neutrophils are less effective at destroying L. monocytogenes-infected target cells in the spleen than in the liver. Consequently, at least during the first day, the organism remained free to multiply intracellularly in the spleen in cells that are permissive for its growth. Presumably, the same situation exists in the peritoneal cavity, because depleting neutrophils did not severely exacerbate infection initiated at this site.
本研究表明，在用单克隆抗体RB6-8C5处理后选择性清除中性粒细胞的小鼠中，在感染关键的第一天，肝脏中的李斯特菌病严重加剧，但脾脏或腹腔中的情况并非如此。在中性粒细胞减少的小鼠肝脏的感染部位，单核细胞增生李斯特菌在肝细胞内大量生长。相比之下，在正常小鼠的肝脏中，中性粒细胞迅速在感染灶积聚，这与被感染肝细胞的裂解有关，而这种裂解有助于在这些易感染细胞中终止感染。在脾脏中情况则不同，中性粒细胞的减少并未导致感染明显加剧。在这个器官中，无论是否存在大量中性粒细胞，在感染灶都能发现完整的被感染细胞，其中许多似乎是成纤维细胞样的基质细胞。这表明中性粒细胞在脾脏中破坏被单核细胞增生李斯特菌感染的靶细胞的效率低于在肝脏中。因此，至少在第一天，该病原体在其能够生长的易感染细胞内仍可在脾脏中自由繁殖。据推测，腹腔中情况相同，因为清除中性粒细胞并没有严重加剧在此部位引发的感染。
