Molloy R G, Nestor M, Collins K H, Holzheimer R G, Mannick J A, Rodrick M L
Department of Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115.
Surgery. 1994 Mar;115(3):341-8.
Severe thermal injury is associated with major alterations in cell-mediated immunity. Because most B-cell responses are regulated or critically dependent on T-cell help, it is not surprising that many studies have also shown a variety of defects in humoral immunity after thermal injury. However, the nature of the relationship between the in vitro ability to produce antibody and subsequent in vivo responses remains unclear.
With a murine model of thermal injury, the primary and secondary humoral immune response to tetanus toxoid (TT) was examined during a 6-week period after sham burn or burn injury. Serum anti-TT titers and the numbers of anti-TT-secreting splenocytes were determined.
Splenocytes from burned animals displayed normal or decreased TT-specific immunoglobulin (Ig) M plaque formation. In contrast, however, IgG plaque formation was persistently increased for up to 6 weeks after thermal injury, suggesting a switch from IgM to IgG antibody production. Conversely serum titers of TT-specific IgG antibody were persistently lower in burn, compared with sham groups. Changes in serum immunoglobulin levels did not account for this marked discrepancy between enhanced in vitro IgG plaque formation but impaired in vivo levels of TT antibody.
The data suggest that thermal injury is associated with a diminished ability to propagate and maintain a normal IgG antibody response, despite the presence of normal or increased numbers of antigen-specific B cells.
严重热损伤与细胞介导免疫的重大改变相关。由于大多数B细胞反应受T细胞辅助调节或严重依赖T细胞辅助，因此许多研究也表明热损伤后体液免疫存在多种缺陷也就不足为奇了。然而，体外产生抗体的能力与随后的体内反应之间关系的本质仍不清楚。
利用热损伤小鼠模型，在假烧伤或烧伤后的6周内检测对破伤风类毒素（TT）的初次和二次体液免疫反应。测定血清抗TT滴度和抗TT分泌脾细胞的数量。
烧伤动物的脾细胞显示出正常或降低的TT特异性免疫球蛋白（Ig）M空斑形成。然而，相比之下，热损伤后长达6周，IgG空斑形成持续增加，表明抗体产生从IgM转变为IgG。相反，与假手术组相比，烧伤组中TT特异性IgG抗体的血清滴度持续较低。血清免疫球蛋白水平的变化并不能解释体外IgG空斑形成增强但体内TT抗体水平受损之间的这种明显差异。
数据表明，尽管抗原特异性B细胞数量正常或增加，但热损伤与传播和维持正常IgG抗体反应的能力下降有关。
