Appelboom T, Persellin R H
Int Arch Allergy Appl Immunol. 1984;74(3):200-5. doi: 10.1159/000233543.
The leukocyte adherence inhibition (LAI) test in arthritis can serve as an in vitro model for investigating cellular cooperation between mononuclear cells sensitized by cytophilic IgG rheumatoid factor(s) present in rheumatoid arthritis (RA) serum, normal synovial components, and polymorphonuclear cells. Since inflammatory and immunologic responses are altered during pregnancy, we studied the effect of pregnancy serum on the LAI. The adherence of normal leukocytes once sensitized in RA serum is inhibited by a synovial extract, but when these leukocytes are exposed to pregnancy serum prior to sensitization with RA serum, the cells are unresponsive to subsequent stimulation by the synovial extract (p less than 0.01). This blocking effect on sensitization is only present in serum obtained after the first trimester of pregnancy and can be detected even at serum dilutions of 1:100. Leukocytes obtained directly from pregnant subjects, washed, and then incubated with RA serum failed to react. Since pregnancy serum has been shown to mask certain cell membrane receptors, it is possible that our results are due to the blocking of IgG rheumatoid factor binding to mononuclear cells. This finding could contribute to the subsidence during pregnancy of some disorders such as rheumatoid arthritis.
关节炎中的白细胞黏附抑制（LAI）试验可作为一种体外模型，用于研究类风湿关节炎（RA）血清中存在的嗜细胞性IgG类风湿因子致敏的单核细胞、正常滑膜成分和多形核细胞之间的细胞合作。由于孕期炎症和免疫反应会发生改变，我们研究了妊娠血清对LAI的影响。在RA血清中致敏过的正常白细胞的黏附会被滑膜提取物抑制，但当这些白细胞在用RA血清致敏前先接触妊娠血清时，细胞对随后滑膜提取物的刺激无反应（p<0.01）。这种对致敏的阻断作用仅存在于妊娠头三个月后获得的血清中，即使在血清稀释至1:100时也能检测到。直接从妊娠受试者获取的白细胞，经洗涤后再与RA血清孵育则无反应。由于已表明妊娠血清会掩盖某些细胞膜受体，我们的结果可能是由于IgG类风湿因子与单核细胞的结合被阻断。这一发现可能有助于解释孕期某些疾病（如类风湿关节炎）病情缓解的原因。
