Oral microbial associations in HIV+subjects

描述（由申请方提供）：本提案的主要目的是检验以下假设：HIV+受试者中更常见的牙周感染是由特定的细菌或真菌物种引起的，这些细菌或真菌物种不一定是通常在HIV阴性受试者的可比牙周感染中发现的典型推定牙周病原体。 我们的初步数据表明，患有坏死性溃疡性牙周炎（NUP）的HIV+受试者，这些个体特有的更严重的牙周疾病，确实缺乏许多经典的牙周病原体，而是拥有“不寻常的”分类群，如Bulleidia extructa和Dialister pneumosintes，以及新的“不可培养的”Dialister属，Peptostrephin，Selenomonas，和“不可培养”的TM 7门的成员。 我们的目标体现在两个具体目标中。 目的1将确定主要的可培养和尚未培养的细菌和真菌，与牙周感染的HIV+受试者，如牙龈炎，低/中度和重度成人牙周炎，和线性牙龈红斑（LGE），另一种牙周感染独特的HIV+受试者。 这些研究将通过分析噬菌斑文库克隆中插入片段的细菌16 S rRNA和真菌18 S rRNA基因序列来进行。 通过PCR扩增龈下菌斑中存在的rRNA基因，然后将扩增子连接到适当的载体中，并通过转化E.杆菌 每个克隆的序列将用于确定物种身份，或者如果未知，则确定其系统发育位置。 预计将确定另外25至50个新的分类群。 目的2将测试的假设，特定的细菌和真菌物种与牙周感染与免疫状态恶化的HIV+患者。 在每个牙周疾病类别中，将分析25名高病毒载量和低CD 4水平的受试者以及25名低病毒载量和高CD 4水平的受试者。 将在这些HIV+组与HIV阴性受试者的对照组之间比较龈下微生物和真菌种群。将使用生物标记板杂交法对每份样本进行多达200种主要细菌菌种的测定，该方法允许使用多个探针同时分析多个样本。 在第二次单独的棋盘杂交中，将对每份样本进行多达30种真菌物种的测定。 可能是特定的细菌复合物（例如，细菌/真菌的特定组合）与这些牙周病有关，并且可能随着HIV感染的严重程度而改变。 拟议的研究可能会提供洞察力的身份，推定的病原体在可比的牙周感染艾滋病毒阴性的个人。

DESCRIPTION (provided by applicant): The broad objectives of this proposal are to examine the hypothesis that the more common periodontal infections in HIV+ subjects are caused by specific bacterial or fungal species, which are not necessarily the typical putative periodontal pathogens usually found in comparable periodontal infections in HIV negative subjects. Our preliminary data indicated that HIV+ subjects with necrotizing ulcerative periodontitis (NUP), a more severe periodontal disease unique to these individuals, indeed lacked many of the classical periodontal pathogens, but instead possessed "unusual" taxa, such as Bulleidia extructa and Dialister pneumosintes, and novel "uncultivable" phylotypes of the genera Dialister, Peptostreptococcus, Selenomonas, and members of the "uncultivable" phylum TM7. Our objectives are addressed in two Specific Aims. Aim 1 will identify the predominant cultivable and not-yet-cultivated bacteria and fungi that are associated with periodontal infections in HIV+ subjects, such as gingivitis, low/moderate and severe adult periodontitis, and Linear Gingival Erythema (LGE), another periodontal infection unique to HIV+ subjects. These studies will be performed by analyzing bacterial 16S rRNA and fungal 18S rRNA gene sequences of inserts in clones from plaque libraries. The libraries will be generated by PCR amplification of rRNA genes present in subgingival plaque followed by ligation of the amplicons into appropriate vectors and by transformation of E. coli. The sequence of each clone will be used to determine species identity, or if unknown, its phylogenetic position. It is anticipated that 25 to 50 additional new taxa will be identified. Aim 2 will test the hypothesis that specific bacterial and fungal species are associated with periodontal infections with the deterioration of immune status in HIV+ patients. In each periodontal disease category, 25 subjects with high viral loads and low CD4 levels and 25 subjects with low viral load and high CD4 levels will be analyzed. Comparisons of subgingival microbial and fungal populations will be made between these HIV+ groups vs. control groups of HIV negative subjects. Up to 200 predominant bacterial species will be assayed for each sample using Checkerboard hybridization, which allows for the simultaneous analysis of multiple samples with multiple probes. Up to 30 fungal species will be assayed for each sample in a second, separate checkerboard hybridization. It is likely that specific bacterial complexes (e.g., specific combinations of bacteria/fungi) are associated with these periodontal diseases and may change with the severity of HIV infection. The proposed studies may provide insight for the identity of putative pathogens in comparable periodontal infections in HIV negative individuals.