Parbhakar Om P, Duke Tanya, Townsend Hugh G G, Singh Baljit
Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, 52 Campus Drive, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada.
Vet Res. 2004 Jan-Feb;35(1):39-51. doi: 10.1051/vetres:2003041.
Pulmonary intravascular macrophages (PIMs) are present in horses and are believed to increase their sensitivity to endotoxin-induced cardio-pulmonary shock. However, owing to a lack of a marker for PIMs and the inability to isolate them, their precise contributions in the horse remain unknown. We designed this study to identify an immuno-phenotypic marker for PIMs and to develop a protocol for their transient depletion with gadolinium chloride (GC). GC is a lanthanide that has been used to deplete liver and lung macrophages. The horses (N = 15) were divided into control (n = 5) and GC-treated (n = 10) groups and the lung samples were examined by routine and immunocytochemical light and electron microscopy. GC-treated horses were euthanized at 48 h (n = 6) and 72 h (n = 4) post-treatment. The PIMs reacted with MAC-387 but not with ED-1 and CD-68 anti-macrophage antibodies. GC reduced the number of PIMs in horses at 48 and 72 h compared with the control (p < 0.05). There were increased intravascular TUNEL-positive cells in GC-treated horses and electron microscopy showed apoptotic PIMs in these horses. These data show that MAC-387 is a reliable marker for PIMs and GC is a safe tool to reduce the number of PIMs.
肺血管内巨噬细胞（PIMs）存在于马体内，据信会增加其对内毒素诱导的心肺休克的敏感性。然而，由于缺乏PIMs的标志物且无法分离它们，它们在马体内的确切作用仍然未知。我们设计了这项研究，以确定PIMs的免疫表型标志物，并制定用氯化钆（GC）短暂清除它们的方案。GC是一种镧系元素，已被用于清除肝脏和肺巨噬细胞。将马（N = 15）分为对照组（n = 5）和GC处理组（n = 10），并通过常规和免疫细胞化学光镜及电镜检查肺样本。GC处理的马在处理后48小时（n = 6）和72小时（n = 4）实施安乐死。PIMs与MAC - 387反应，但不与ED - 1和CD - 68抗巨噬细胞抗体反应。与对照组相比，GC在48小时和72小时时减少了马体内PIMs的数量（p < 0.05）。GC处理的马体内血管内TUNEL阳性细胞增加，电镜显示这些马体内有凋亡的PIMs。这些数据表明MAC - 387是PIMs的可靠标志物，GC是减少PIMs数量的安全工具。
