Melanoma vaccines using MHC-associated peptides

描述（由申请人提供）：理解皮肤疫苗接种免疫生物学的经典范例是抗原与佐剂一起递送产生炎症刺激，进而诱导表皮朗格汉斯细胞成熟并迁移到引流淋巴结。然而，重复接种黑色素瘤肽佐剂与严重的慢性局部炎症有关，可能具有不同的生物学特性。自身免疫性疾病和感染性疾病的慢性炎症可在非典型淋巴样区产生新的淋巴样组织。这一过程被称为“淋巴样新生”，可导致功能类似淋巴结的三级淋巴样器官（TLO）。我们观察到，单次注射不完全弗氏佐剂加GM-CSF的乳剂后，人皮肤真皮层出现淋巴结样聚集物（LNLA）。这些LNLA含有成熟的CD83+DC-LAMP+树突状细胞、T细胞、B细胞和外周节点寻址蛋白（PNAd），表达微血管，提示高内皮小静脉。在佐剂重复肽疫苗接种部位的初步研究显示淋巴样新生的其他特征，但也有证据表明聚集体中有调节细胞。我们假设：(i)重复接种黑色素瘤肽和佐剂可能导致LNLA持续存在，并在疫苗部位产生三级淋巴器官；（ii）延长免疫接种可能导致一系列继发性免疫调节影响，如果确定其流行程度和时间，则可以有针对性地阻断这些影响；（iii）抗原特异性CD4+和CD8+ T细胞在疫苗部位局部诱导，可通过将肽抗原直接引入预诱导免疫微环境中产生。因此，对于目前的建议，我们建议进行两项临床试验，将免疫与具有良好特征的多肽疫苗结合起来，并对从重复免疫部位获得的组织进行广泛研究。具体目标是：目标1。目的2：确定含有或不含多肽的“佐剂”重复免疫（1-3次）是否诱导皮肤淋巴结样聚集体（LNLA）和三级淋巴器官（TLO）。为了确定扩大免疫（4-6种疫苗）是否与接种部位微环境/三级淋巴器官的免疫调节过程的诱导有关，目的3。研究多肽疫苗免疫部位的抗原反应性CD4和CD8 T细胞。这项工作的结果可能会改变我们对免疫微环境中免疫生物学的理解，并确定提高抗肿瘤免疫的联合治疗方法。公共卫生相关性：癌症疫苗有望作为一种低毒性治疗方法，利用免疫系统对癌症的反应，特别是对黑色素瘤的反应。黑色素瘤疫苗可以在许多或大多数患者中诱导免疫反应，但临床效果令人失望。目前的建议是表征与黑色素瘤疫苗诱导免疫反应相关的细胞和分子事件，目的是通过更好地了解这些事件来提高疫苗的治疗潜力。

DESCRIPTION (provided by applicant): The classic paradigm for understanding the immunobiology of cutaneous vaccination is that antigen delivered with an adjuvant creates an inflammatory stimulus, which in turn induces epidermal Langerhans cells to mature and to migrate to draining lymph nodes. However, repeat vaccination with melanoma peptides in adjuvant is associated with dramatic chronic local inflammation and may have different biology. Chronic inflammation in autoimmune and infectious diseases can lead to new lymphoid tissues in locations that are not classic lymphoid areas. This process, termed "lymphoid neogenesis," can result in tertiary lymphoid organs (TLO) that function like lymph nodes. We have observed lymph node-like aggregates (LNLA) in the dermis of human skin after a single injection of an emulsion of incomplete Freund's adjuvant plus GM-CSF. These LNLA contain mature CD83+DC-LAMP+ dendritic cells, T cells, B cells, and peripheral node addressin (PNAd) expressing microvessels suggestive of high endothelial venules. Preliminary studies in sites of repeated peptide vaccination with adjuvant show other features of lymphoid neogenesis, but there also is evidence of regulatory cells in the aggregates. We hypothesize that: (i) repeat vaccination with melanoma peptides and adjuvant may cause persistence of LNLA and creation of tertiary lymphoid organs at vaccine sites, (ii) extending immunization may result in a secondary set of immune regulatory influences, which could be blocked in a targeted manner if their prevalence and timing is defined, and (iii) antigen specific CD4+ and CD8+ T cells are induced locally at vaccine sites and may be generated by direct introduction of peptide antigens into a pre-induced immunization microenvironment. Thus, for the current proposal, we propose to perform 2 clinical trials combining immunization with a well- characterized multipeptide vaccine with extensive studies of tissue obtained from a replicate immunization site. Specific aims are: Aim 1. To determine whether repeat immunization (1-3 times) with "Adjuvant" with or without peptides induces lymph-node like aggregates (LNLA) and tertiary lymphoid organs (TLO) in skin, Aim 2. To determine whether extended immunization (4-6 vaccines) is associated with induction of immune regulatory processes in the vaccination site microenvironment /tertiary lymphoid organs, Aim 3. To characterize antigen-reactive CD4 and CD8 T cells in sites of immunization with a multipeptide vaccine. The results of this work will likely change our understanding of the immunobiology in the immunization microenvironment and identify approaches for combination therapies to improve antitumor immunity. PUBLIC HEALTH RELEVANCE: Cancer vaccines hold promise as a low toxicity treatment that may harness the immune system's response to cancer, and to melanoma in particular. Melanoma vaccines can induce immune responses in many or most patients, but the clinical impact has been disappointing. The present proposal is to characterize cellular and molecular events associated with induction of immune responses by melanoma vaccines, with the intent of improving the therapeutic potential of vaccines through a better understanding of these events.