EVOLUTION AND PROPERTIES OF HIV/SIV STRAINS IN CAMEROON

SIVcpz和HIV-1的遗传相关性支持了跨物种传播的假设，并表明在喀麦隆发现的HIV-1的三个主要群体（M，O和N）是单独引入人类的结果。 喀麦隆人口具有遗传多样性，有250多个民族居住在偏远的村庄。由于跨物种传播可能发生在喀麦隆遗传多样性的不同区域，最近引入的SIV/HIV-1毒株可能在小型和偏远社区单独进化，然后在人类遗传环境由不同群体和地区组成的城市中心传播和进一步进化。 此外，由于亚型的差异可能最初发生在或可能发生在少数种族群体中，其中人类遗传多样性受到文化和地理因素的限制，因此每个种族群体内的SIV/HIV-1毒株的差异也可能有限，导致相对受限的免疫学和生物学特征。 目前迫切需要进行研究，以了解SIV/HIV在不同地方社区的演变，因为新建道路将这些社区连接起来，从而增加了相互作用。 此外，在喀麦隆城市地区，有记录表明存在多种艾滋病毒群或亚型或重组病毒的感染，但对这些病毒的演变情况知之甚少。由于缺乏关于从其SIV祖先进化很少的病毒的信息，以及关于来自多重和重组HIV感染的病毒的信息，我们提出了以下工作：为了确定HIV-1变异体在不同人类种族群体、风险群体、和地理位置，并研究特定的HIV-1毒株是否只存在于或优先存在于任何这些研究人群中。 目标2：研究AIM 1中发现的HIV-1毒株的抗原和生物学特征，并确定其特征与不同种族群体、风险群体和发现它们的地理区域之间的关系。AIM 3：监测感染多种HIV-1组/亚型、重组体和“纯亚型”的患者的病毒演变和疾病进展：AIM 4：比较亚型间重组体和“纯亚型”感染者的病毒突变率和性质（作为病毒进化的一种衡量标准），并将这些变化与宿主的体液免疫反应相关联。 目的5：确定在喀麦隆不同地理区域的非人灵长类宠物中SIVcpz样感染的分布。

The genetic relatedness of SIVcpz and HIV-1 supports the hypothesis of cross-species transmission and suggests that the three main groups of HIV-1 (M, O, and N), all found in Cameroon, are a result of separate introductions into humans. The Cameroon population is genetically diverse, with more than 250 ethnic groups living in isolated villages. Because cross-species transmissions may occur in distinct pockets of genetic diversity in Cameroon, recently introduced SIV/HIV-1 strains could be evolving separately in small and remote communities before spreading and further evolving in urban centers where the human genetic environment consists of a composite from various groups and locales. Furthermore, because the divergence of the subtypes may have originally occurred or may be occurring in a few ethnic groups where human genetic diversity is limited by cultural and geographic factors, the divergence of SIV/HIV-1 strains within each ethnic group may also be limited, resulting in relatively restricted immunologic and biologic characteristics. Studies are urgently needed at this point in time to understand the evolution of SIV/HIV in distinct local communities because new roads are linking these communities and thus increasing interaction. In addition, infection with multiple HIV groups or subtypes, or with recombinant viruses, has been documented in urban areas of Cameroon, yet little is known of the evolution of these viruses. Because information about viruses which have evolved little from their SIV ancestors is lacking, as is information about viruses from multiple and recombinant HIV infections, we propose the following work: AIM l: To identify the distribution of HIV-1 variants circulating in different human ethnic groups, risk groups, and geographic locales in Cameroon and to study whether specific strains of HIV-1 exist exclusively or preferentially within any of these study populations. AIM 2: To study the antigenic and biologic characteristics of the HIV-1 strains found in AIM 1 and determine how their characteristics correlate with the different ethnic groups, risk groups, and geographic locales in which they are found. AIM 3: To monitor the viral evolution and disease progression in patients infected with multiple HIV-1 groups/subtypes, recombinants and "pure subtypes": AIM 4: To compare the rates and nature of mutations of viruses (as a measure of viral evolution) from persons infected with inter-subtype recombinants and "pure subtypes" and to correlate these changes with the host's humoral immune response. AIM 5: To identify the distribution of SIVcpz-like infections among non-human primate pets in the different geographic locales of Cameroon.