CpGs are oligonucleotides containing CpG motifs much like those observed in bacterial DNA. for the assessment of human T-cell responses, revealing in part unprecedented insight into T-cell biology and novel structural principles that govern TCR-pMHC acknowledgement. Together, the explained approaches advance our knowledge of T-cell mediated-protection from human diseases. == 1. Introduction == Despite PAC major developments in the fields of molecular and cellular biology, and the improved understanding of malignancy formation and progression, the surgical removal of tumors remains the most effective therapeutic strategy against malignancy. While radiation therapy and chemotoxic drugs are often employed to successfully prolong the disease-free survival or to slow down tumor progression, their limited specificity in targeting neoplastic cells is usually often responsible for a wide spectrum of common clinical side effects. In this respect, immunotherapy is usually a promising therapeutic alternative to avoid PAC such side effects by activating the patient’s own immune system against tumor cells. In this Paper we focused on selected aspects of current vaccination strategies against melanoma, as well as new and sophisticated tools employed by immunologists to analyze cellular immune responses by zooming in on single tumor-specific lymphocytes. == 1.1. Melanoma == Melanoma arises from the pigment-producing melanocytes. It is the major cause of mortality among skin malignancies. The incidence is steadily increasing at rates over 3% per year, with many hundreds of new cases per 100 000 inhabitants, and mortality rates ranging from 0.1 to >10% [1]. These figures, however, differ largely depending on Ly6a risk factors such as sun exposure depending on the local climate. Melanoma is one of the most antigenic and immunogenic cancers with a high percentage of tumors expressing well-characterized tumor-associated antigens. Immunotherapy targeting one or several of these tumor-expressed antigens has shown promising results over the past years in enhancing antitumor immune responses. It is now well established that spontaneous tumor antigen-specific T-cell responses are generated in melanoma patients that can be detected both in the blood circulation as well as at the tumor sites. While spontaneous T-cell responses have been reported against cancer-germline antigens encoded by the MAGE family, and against NY-ESO-1, T-cell frequencies are generally very low (107to 104) [2]. An exception to this is the natural immune response observed in most melanoma patients against the Melan-A/MART1 differentiation antigen offered in the context of the MHC class I molecule HLA-A2. In untreated patients, frequencies of T-cells specific for this antigen usually range from 0.01% to 0.1% of total circulating CD8poscells [3,4]. These frequencies are often much higher in metastatic lymph nodes and other metastases of melanoma patients [5,6]. In fact unusually high frequencies (103to 104) of A2/Melan-A-specific T lymphocytes are already found in the blood of newborns and healthy A2+ individuals. This populace of self-peptide specific T-cells is usually preferentially selected in the thymus, presumably due to cross reactivity to unknown self-peptides. Consequently, large numbers of such cells are released from your thymus into the periphery as mature, naive precursor T-cells PAC [7,8]. Thus, the activation and growth of this populace of Melan-A-specific PAC CD8 T lymphocytes to induce clinically relevant tumor cell lysis represents an important target of immunotherapy. == 1.2. Restorative Immunization Strategies == The purpose of an efficient cancers vaccine can be to activatede novothe disease fighting capability against tumor cells and/or to improve the preexisting tumor-specific response. A perfect vaccine would induce enlargement of huge populations of cytotoxic T-cells, with potent antitumor effector features, both in the tumor-site but like a systemic defense monitoring for extended periods of time also. The decision of adjuvants and antigenic peptides utilized, their mixture, and timing are essential elements. Currently you can find three major techniques of immunotherapy: antigen-based vaccines, adoptive PAC cell transfer of effective antitumor T-cells, and excitement from the immune system within an antigen-nonspecific way. Optimal vaccines contain attenuated or live microbes. However, for most infectious diseases, as well as for cancers generally, such vaccines aren’t available. Therefore, artificial vaccines are made following a rational-based microbe-induced immune system mechanisms generally. Synthetic vaccines are comprised of at least two fundamental parts: antigen and adjuvant. The logical of using antigens for tumor immunotherapy is dependant on the fairly huge consensus that immune system safety against malignant disease needs antigen-specific (adaptive) immune system reactions including T-cells. Some specialists argue that excitement from the innate disease fighting capability alone could be sufficient to create tumor-specific immunity, since tumor cells makes tumor antigens allowing some activation of antigen-specific immune system reactions often. Therefore, a growing number of book.