长白山区莱姆病调查与实验室分析

目的：了解长白山区莱姆病传播媒介－全沟硬埤的地理位置,分布及其病原携带情况。方法：用酶联免疫吸附试验,间接免疫荧光试验检测莱姆病特异IgG抗体,结果：长白山区抓捕的620只硬蜱,全沟硬蜱为593只,占总数的95．80％,用BSK培养基33度培养,分纯后共获得纯阳性和伯氏疏螺旋体培养物243株,用免疫抗美国B31特异性多克隆抗体和针对莱姆病螺旋体种属特异单克隆抗体,间接免疫荧光荧光抗体试验进行鉴定,证明其单克隆抗体反应与美国菌株稍有差异,与国内分离株M7相同,血检826人,IgG,IgM大于等于1：128（抗体滴度）有49例,阳性率为5．93％,IgG,IgM大于等于1：64（抗体滴度）有82例;二项合计为15．85％,结论：长白山区是莱姆病重要疫源地,人群中有莱姆病感染存在,并有莱姆病发生。     

广东省莱姆病宿主动物和媒介生物调查

目的 :了解广东省鼠和蜱携带莱姆病病原体情况。方法 :BSK培养基从鼠脏器和蜱悬液分离伯氏疏螺旋体 ,单克隆抗体鉴定。结果 :检验 316只鼠的脏器和 4 90匹蜱的悬液 ,从白腹巨鼠的胚胎和针毛鼠的膀胱各分离到 1株伯氏疏螺旋体 (LPR30、HJR56 ) ,它们都对单克隆抗体H5332 、H972 4 呈阳性反应 ,而对H6 831呈阴性。结论 :白腹巨鼠和针毛鼠是莱姆病宿主动物     

Ligand‐presenting assembly: a method for C‐ and N‐terminal antigen presentation

Abstract: Achiral dicarboxylic acids were coupled with 2 eq. of the free α‐amino groups of two fully side‐chain protected peptide chains while these were still attached to a synthesis resin. Cleavage from the resin with simultaneous side‐chain deprotection afforded two assembled peptide chains with free C‐terminals. Suitable functionalization of the achiral dicarboxylic acid alternatively permited continued peptide synthesis in a C to N orientation leading to a final peptide assembly which, after cleavage from the resin, may have multiple N to C and C to N presentation of one or more epitopes.     

Accident ischémique cérébral lié à une neuroborréliose

Ischemic stroke in children is rare and its etiology is frequently unknown. CASE REPORT: We report the case of a nine-year-old boy who presented a right ischemic lenticular stroke due to neuroborreliosis, with a good outcome after antibiotic treatment. CONCLUSION: We suggest that it is important to search for neuroborreliosis in case of an ischemic stroke in children; the study of cerebral spinal fluid is a good diagnostic marker.     

Lyme neuroborreliosis: An unusual case with extensive (peri)vasculitis of the middle cerebral artery

Lyme disease is a tick-borne infection caused by Borrelia burgdorferi sensu latu. Neuroborreliosis is reported in approximately 10% of patients with Lyme disease. We report a patient with central nervous system (CNS) large vessel vasculitis, ischemic stroke, and tumefactive contrast-enhancing brain lesions, an unusual complication of neuroborreliosis. A 56-year-old man presented with headache and disorientation for 1 month. Magnetic resonance imaging revealed basal meningitis with rapidly progressing frontotemporoinsular edema and (peri)vasculitis. Transcranial ultrasound confirmed stenosed medial cerebral arteries. [¹⁸F]GE-180 microglia positron emission tomography (PET) showed frontotemporoinsular signal more pronounced on the right. [¹⁸F]FET amino acid PET demonstrated low tracer uptake, suggesting an inflammatory process. Cerebrospinal fluid (CSF) showed lymphomonocytosis (243/μl), intrathecal anti-Borrelia IgM (CSF/serum index = 15.65, normal < 1.5) and anti-Borrelia IgG (CSF/serum index = 6.5, normal < 1.5), and elevated CXCL13 (29.2 pg/ml, normal < 10 pg/ml). Main differential diagnoses of neurotuberculosis and perivascular CNS lymphoma were ruled out by biopsy and Quantiferon enzyme-linked immunosorbent assay. Ceftriaxone (28 days), cortisone, and nimodipine (3 months) led to full recovery. Neuroborreliosis is an important differential diagnosis in patients with CNS large vessel vasculitis and tumefactive contrast-enhancing brain lesions, mimicking perivascular CNS lymphoma or neurotuberculosis as main neuroradiological differential diagnoses. Vasculopathy and cerebrovascular events are rare in neuroborreliosis but should be considered, especially in endemic areas.     

莱姆病螺旋体83kd抗原蛋白基因特异性区段真核及原核表达型载体的构建

从莱姆病螺旋体染色体编码８３ｋｄ抗原蛋白（Ｐ８３）基因序列中选择编码近Ｃ端１５９个氨基酸的基因序列作为扩增的靶序列，自行设计并合成一对寡核苷酸引物，以莱姆病螺旋体Ｂ３１株基因组ＤＮＡ为模板，通过ＰＣＲ扩增得到约４７７ｂｐ的扩增片段，再把该片段与质粒载体ｐＢＫ－ＣＭＶ进行重组，经鉴定得到重组质粒ｐＢＸ１。重组质粒ｐＢＸ１可同时在真核和原核细胞中表达，其表达产物可用来制备莱姆病血清学诊断用的标准抗原；该重组质粒也可用来制备用于对莱姆病螺旋体进行分类鉴定的核酸探针。     

Plasma neurofilament light significantly decreases following treatment in Lyme neuroborreliosis and is not associated with persistent symptoms

Background and purpose

Currently there is an unmet need for a highly standardized blood biomarker test to monitor treatment response in Lyme neuroborreliosis (LNB). Differentiating between active or past infection is challenged by the relatively high frequency of persistent symptoms after the end of antibiotic treatment (estimated 15%–20%), the variable clinical course and the long-lasting Borrelia burgdorferi antibodies. The aim was therefore to evaluate plasma neurofilament light chain (pNfL) as a marker for disease activity in LNB.

Methods

This was a prospective cohort of definite LNB (N = 36) with blood samples and clinical evaluation including Glasgow Outcome Score at treatment initiation and 3 and 6 months’ follow-up. Consecutive plasma was retrospectively analysed for the content of neurofilament light chain by Quanterix® kits (Simoa® NF-light Kit).

Results

Plasma neurofilament light chain significantly decreased between treatment initiation and the 3-month follow-up (median 83 pg/ml vs. median 14 pg/ml (25 pairs), p < 0.0001). No significant change was observed between 3 and 6 months’ follow-up (median 14 pg/ml vs. median 12 pg/ml (21 pairs), p = 0.33). At treatment initiation 90% had pNfL above the age-defined reference compared to only 23% and 7% respectively at 3 and 6 months’ follow-up. Decreases in pNfL were mirrored by increasing Glasgow Outcome Score. Reporting persistent symptoms at the 6-month follow-up was not associated with pNfL (relative change from reference or actual values) at baseline or at 6 months’ follow-up.

Conclusion

Plasma neurofilament light chain decreases following antibiotic treatment in LNB and is not associated with reporting persistent symptoms. It was therefore speculated that it may prove useful as a treatment response biomarker in LNB.     

Specific mRNA lipid nanoparticles and acquired resistance to ticks

Acquired resistance to ticks can develop when animals are repeatedly exposed to ticks. Recently, acquired resistance to Ixodes scapularis was induced in guinea pigs immunized with an mRNA-lipid nanoparticle vaccine (19ISP) encoding 19 I. scapularis proteins. Here, we evaluated specific mRNAs present in 19ISP to identify critical components associated with resistance to ticks. A lipid nanoparticle containing 12 mRNAs which included all the targets within 19ISP that elicited strong humoral responses in guinea pigs, was sufficient to induce robust resistance to ticks. Lipid nanoparticles containing fewer mRNAs or a single mRNA were not able to generate strong resistance to ticks. All lipid nanoparticles containing salp14 mRNA, however, were associated with increased redness at the tick bite site – which is the first manifestation of acquired resistance to ticks. This study demonstrates that more than one I. scapularis target within 19ISP is required for resistance to ticks, and that additional targets may also play a role in this process.