New insights into the pathogenesis of giant cell arteritis

Giant cell arteritis (GCA) is an inflammatory chronic disease occurring exclusively in elderly individuals. Until recently, the disease has been considered a unique disease resulting from the interaction in the walls of susceptible arteries, between an unknown infectious agents with local dendritic cells (DCs), activated CD4 T cells and effector macrophages. Recent evidence has shown that this view was too simplistic and has clarified many of the pathogenetic aspects of the disease. Many genetic studies recently published have identified different new genes, including cytokines, adhesion molecules and regulators of innate immunity, as crucial players in the development and progression of GCA. Recent evidence suggests that there is heterogeneity of histological lesions in GCA, that are correlated with different immunological Th9 and Th17 signature. The recent demonstration that Varicella-zoster virus (VZV) antigen is present in the 64% of GCA-negative TAs and in the 73% of GCA-positive TAs could represent an important point of arrival in the search for a causative agent in the pathogenesis of a metameric disease such as GCA. In this context, cytokines such as IL-32 and IL-33 that act as a danger signal following tissue damage and infection are over-expressed in GCA arteries. Artery tertiary lymphoid organs, present in up to 50% of GCA-positive arteries, could represent the sites were primary immune responses and T- and B-cell autoimmune responses against viral antigens are organized. The recently demonstrated disturbed distribution of B cells in GCA could be also relevant in the pathogenesis of the disease, possibly contributing to the enhanced IL-6 response. Altogether, these evidences may clarify many pathogenetic aspect of the disease, also suggesting complexity greater than first imagined

Significant Impact of Immunogen Design on the Diversity of Antibodies Generated by Carbohydrate-Based Anticancer Vaccine

Development of an effective vaccine targeting tumor associated carbohydrate antigens (TACAs) is an appealing approach toward tumor immunotherapy. While much emphasis has been typically placed on generating high antibody titers against the immunizing antigen, the impact of immunogen design on the diversity of TACA-specific antibodies elicited has been overlooked. Herein, we report that the immunogen structure can significantly impact the breadth and the magnitude of humoral responses. Vaccine constructs that induced diverse TACA-binding antibodies provided much stronger recognition of a variety of Tn positive tumor cells. Optimization of the breadth of the antibody response led to a vaccine construct that demonstrated long lasting efficacy in a mouse tumor model. After challenged with the highly aggressive TA3Ha cells, mice immunized with the new construct exhibited a statistically significant improvement in survival relative to controls (0% vs 50% survival; <i>p</i> < 0.0001). Furthermore, the surviving mice developed long-term immunity against TA3Ha. Thus, both the magnitude and the breadth of antibody reactivity should be considered when designing TACA-based antitumor vaccines

New insights into the pathogenesis of giant cell arteritis

Giant cell arteritis (GCA) is an inflammatory chronic disease occurring exclusively in elderly individuals. Until recently, the disease has been considered a unique disease resulting from the interaction in the walls of susceptible arteries, between an unknown infectious agents with local dendritic cells (DCs), activated CD4 T cells and effector macrophages. Recent evidence has shown that this view was too simplistic and has clarified many of the pathogenetic aspects of the disease. Many genetic studies recently published have identified different new genes, including cytokines, adhesion molecules and regulators of innate immunity, as crucial players in the development and progression of GCA. Recent evidence suggests that there is heterogeneity of histological lesions in GCA, that are correlated with different immunological Th9 and Th17 signature. The recent demonstration that Varicella-zoster virus (VZV) antigen is present in the 64% of GCA-negative TAs and in the 73% of GCA-positive TAs could represent an important point of arrival in the search for a causative agent in the pathogenesis of a metameric disease such as GCA. In this context, cytokines such as IL-32 and IL-33 that act as a danger signal following tissue damage and infection are over-expressed in GCA arteries. Artery tertiary lymphoid organs, present in up to 50% of GCA-positive arteries, could represent the sites were primary immune responses and T- and B-cell autoimmune responses against viral antigens are organized. The recently demonstrated disturbed distribution of B cells in GCA could be also relevant in the pathogenesis of the disease, possibly contributing to the enhanced IL-6 response. Altogether, these evidences may clarify many pathogenetic aspect of the disease, also suggesting complexity greater than first imagined