Tumor Cell Vaccines

Cancer immunotherapy can be approached through the use of tumor cells as a platform to initiate a therapeutic immune response. Tumor cells by themselves are typically not immunogenic. However, as the science of determining how an effective APC initiates an immune response advance, these strategies are being used to alter tumor cells and render them as loci of immune stimulation. Creative Biolabs is a world leader in the field of cancer vaccine development. With our extensive experience and advanced platform, we are therefore confident in offering the best development services for tumor cell vaccines. We guarantee the finest results for our customers all over the world.

Autologous and allogeneic tumor cells were one of the first types of tumor vaccines to be used. The most general method for cell-based immunotherapy is to use a single representative cancer cell as a universal vaccine for all patients with that same type of cancer. Some investigators consider this approach as suboptimal as it is allogeneic, where the MHC type of the vaccine and the patient do not match, and the immune system may be distracted from generating a tumor–antigen-specific to an allospecific response. Others argue that an allogeneic vaccine will be effective for just this reason and that the alloimmune response will serve to amplify the cancer–antigen-specific response. Preclinical studies in mice have demonstrated robust antitumor responses to whole cell vaccines that are dependent on a variety of immunologic mechanisms, including T cell (both CD4⁺ and CD8⁺) and NK responses, and the presence of macrophages and eosinophils depending on the formulation of the vaccine.

How these vaccines work is poorly defined and remains an area of controversy. The majority of studies indicate a substantial requirement for cytotoxic T cell responses that are elicited through one or both of the following mechanisms:

• The vaccine cells directly prime T cells;
• Vaccine antigens are taken up by professional antigen-presenting cells (APCs), which then stimulate a T cell response, an effect known as cross-priming.

Key Advantage of Tumor Cell Vaccines

• They have all the relevant tumor antigens needed by the immune system to mount an effective antitumor response. This is particularly true if autologous tumor cells are used instead of allogeneic tumor cells;
• Tumor cell-based immunization allows the development of cancer vaccines without knowing the specific antigens.

The advantages of tumor cell-based cancer vaccines must be balanced against two major disadvantages: the potential for autoimmunity and the potential for increasing the anergic status of the T cells due to the lack of functional co stimulatory molecules on tumor cells. Initial attempts to immunize cancer patients with tumor cells were disappointing and temporarily decreased interest in the field.

Development Status of Tumor Cell Vaccines

Highlighted are clinical trials where allogeneic cell lines are used as vaccines for prostate cancer and melanoma and showed extended survival as compared to the control arms. The modification of whole-cell vaccines to elicit a more robust immune response has been addressed in several ways, by the addition of BCG to the vaccine, or the modification of the cells to express costimulatory molecules or secrete cytokines. While autologous whole-cell vaccines are now being tested in combination with chemotherapy, future work is expected to address the efficacy of combination therapy with allogeneic whole-cell vaccines.

Design and Modification of Allogeneic Cell Vaccines

Creative Biolabs provides modification services to improve the efficacy of allogeneic cell vaccines. Tumor cells are generally thought to be poorly immunogenic, although immunogenicity varies considerably between tumors of different backgrounds. We have a variety of strategies that are aimed at improving the immunogenicity of the vaccine including modification of vaccine cells to express costimulatory molecules or cytokines.

Hematopoietic Stem Cell Transplantation (HSCT) Platform

High-dose therapy followed by hematopoietic stem cell transplantation (HSCT) is an attractive platform for cancer vaccine administration since it can achieve both of these goals (reduction of disease to minimal levels and altered immune regulation). Clinical and experimental data have also suggested that the lymphopenic state occurring early after HSCT might allow for better induction and skewing of immunity toward tumor reactivity. Vaccinating early after HSCT has become of particular interest since the mid-1990s as researchers and clinicians strive to improve the efficacy of cancer vaccines.

Costimulatory Molecules Development

Creative Biolabs are developing new molecules that may be included in cell-based vaccines or as targets of immunomodulation in their own right. The molecules that are currently being brought to phase I clinical trials for therapeutic applicability are members of both the PD-1/B7-H1/B7-DC pathway and the CD137/CD137L pathway. We offer development advices on how both positive and negative signals mediated by immune costimulatory molecules orchestrate antitumor immune responses.

Creative Biolabs is a leader in the field of vaccine development and has focused on the cancer vaccines for years. We have experienced experts and advanced platforms that are able to provide excellent services. If you are interested in our services, please contact us for more details.

All of our products can only be used for research purposes. These vaccine ingredients CANNOT be used directly on humans or animals.