Miyata M, Kobayashi H, Sasajima T, Sato Y, Kasukawa R
Fukushima Medical University School of Medicine, Fukushima City, Japan.
Arthritis Rheum. 2000 Nov;43(11):2578-82. doi: 10.1002/1529-0131(200011)43:11<2578::AID-ANR27>3.0.CO;2-V.
To investigate the effects of an intradermal injection of an unmethylated oligodeoxynucleotide (ODN) containing CpG motifs on the severity of collagen-induced arthritis (CIA).
CIA was induced in DBA/1 LacJ mice by immunization with bovine type II collagen (CII) in Freund's complete adjuvant followed 3 weeks later by immunization with CII in Freund's incomplete adjuvant (yielding CIA mice). Unmethylated ODN containing a CpG motif was injected intradermally into DBA/1 LacJ mice at a dosage of 20 microg (yielding CpG-CIA mice) 1 week prior to the first immunization with CII. Unmethylated ODN containing a GpC motif instead of a CpG motif and ODN containing a methylated CpG motif were used to produce controls (GpC-CIA mice and mCpG-CIA mice, respectively). After the second immunization with CII, arthritis scores were measured weekly up to the eighth week. At the eighth week, the mice were killed, histopathologic changes in the ankle joints were examined, and titers of interferon-gamma (IFNgamma) in the supernatants of splenocytes (1 x 10(7)) stimulated in culture by CII for 3 days were determined by enzyme-linked immunosorbent assay.
CpG-CIA mice had significantly higher arthritis scores than CIA mice. CpG-CIA mice had more severe histopathologic changes than CIA mice and mCpG-CIA mice. Moreover, splenocytes in CpG-CIA mice produced higher IFNgamma titers in response to CII than did splenocytes in CIA mice and mCpG-CIA mice.
Injection of unmethylated oligo-DNA containing CpG motifs aggravated CIA through activation of the Th1-type immune response, suggesting that microbial infection could be one of the mechanisms for aggravation or exacerbation of arthritis or, alternatively, that such infection could be an adjuvant in the induction of arthritis in rheumatoid arthritis.
研究皮内注射含CpG基序的未甲基化寡脱氧核苷酸（ODN）对胶原诱导性关节炎（CIA）严重程度的影响。
通过在弗氏完全佐剂中用牛II型胶原（CII）免疫DBA/1 LacJ小鼠诱导CIA，3周后再用弗氏不完全佐剂中的CII免疫（产生CIA小鼠）。在首次用CII免疫前1周，将含CpG基序的未甲基化ODN以20μg的剂量皮内注射到DBA/1 LacJ小鼠体内（产生CpG-CIA小鼠）。使用含GpC基序而非CpG基序的未甲基化ODN和含甲基化CpG基序的ODN分别作为对照（分别产生GpC-CIA小鼠和mCpG-CIA小鼠）。在用CII进行第二次免疫后，每周测量关节炎评分直至第八周。在第八周，处死小鼠，检查踝关节的组织病理学变化，并通过酶联免疫吸附测定法测定在培养中用CII刺激3天的脾细胞（1×10⁷）上清液中干扰素-γ（IFNγ）的滴度。
CpG-CIA小鼠的关节炎评分显著高于CIA小鼠。CpG-CIA小鼠的组织病理学变化比CIA小鼠和mCpG-CIA小鼠更严重。此外，与CIA小鼠和mCpG-CIA小鼠的脾细胞相比，CpG-CIA小鼠的脾细胞对CII产生的IFNγ滴度更高。
注射含CpG基序的未甲基化寡脱氧核糖核酸通过激活Th1型免疫反应加重CIA，提示微生物感染可能是关节炎加重或恶化的机制之一，或者这种感染可能是类风湿关节炎中诱导关节炎的佐剂。
