Prolonged residence of an albumin–IL-4 fusion protein in secondary lymphoid organs ameliorates experimental autoimmune encephalomyelitis

Interleukin-4 (IL-4) suppresses the development of multiple sclerosis in a murine model of experimental autoimmune encephalomyelitis (EAE). Here, we show that, in mice with EAE, the accumulation and persistence in the lymph nodes and spleen of a systemically administered serum albumin (SA)–IL-4 fusion protein leads to higher efficacy in preventing disease development than the administration of wild-type IL-4 or of the clinically approved drug fingolimod. We also show that the SA–IL-4 fusion protein prevents immune-cell infiltration in the spinal cord, decreases integrin expression in antigen-specific CD4+ T cells, increases the number of granulocyte-like myeloid-derived suppressor cells (and their expression of programmed-death-ligand-1) in spinal cord-draining lymph nodes and decreases the number of T helper 17 cells, a pathogenic cell population in EAE. In mice with chronic EAE, SA–IL-4 inhibits immune-cell infiltration into the spinal cord and completely abrogates immune responses to myelin antigen in the spleen. The SA–IL-4 fusion protein may be prophylactically and therapeutically advantageous in the treatment of multiple sclerosis

Enhanced lymph node trafficking of engineered IL‐10 suppresses rheumatoid arthritis in murine models

Objective Rheumatoid arthritis (RA) is a major autoimmune disease that causes synovitis and joint damage. Although clinical trials using interleukin‐10 (IL‐10), an anti‐inflammatory cytokine, have been performed as a potential treatment of RA, its therapeutic effects have been limited, potentially due to insufficient residence in lymphoid organs, where antigen recognition primarily occurs. Here, we engineered IL‐10 as a fusion with serum albumin (SA). Methods SA‐fused IL‐10 was recombinantly expressed. After intravenous injection to mice, retention of SA‐IL‐10 at lymph node (LN), immune cell compositions at paws, and therapeutic effect on arthritis model mice were assessed. Results SA fusion to IL‐10 led to enhanced LN accumulation compared with unmodified IL‐10. Intravenous SA‐IL‐10 treatment restored immune cell composition in the paws to a normal status, elevated the frequency of suppressive M2 macrophages, reduced IL‐17A amount in the paw‐draining LN, and protected joint morphology. Intravenous SA‐IL‐10 treatment showed similar efficacy as treatment with an anti‐TNF‐α antibody. SA‐IL‐10 was equally effective when administered intravenously, locally or subcutaneously, which benefits clinical translation of this molecule. Conclusion SA fusion to IL‐10 is a simple but effective engineering strategy for RA therapy and holds clinical translational potential

Matrix-binding checkpoint immunotherapies enhance antitumor efficacy and reduce adverse events

Immune checkpoint blockade exhibits considerable antitumor activity, but previous studies have reported instances of severe treatment-related adverse events. We sought to explore local immune checkpoint blockade, with an antibody (Ab) form that would be retained intra- or peritumorally, limiting systemic exposure. To accomplish this, we conjugated the checkpoint blockade Abs to an extracellular matrix (ECM)–super-affinity peptide derived from placenta growth factor–2 (PlGF-2123–144). We show enhanced tissue retention and lower Ab concentrations in blood plasma after PlGF-2123–144 conjugation, reducing systemic side effects such as the risk of autoimmune diabetes. Peritumoral injections of PlGF-2123–144–anti-CTLA4 (cytotoxic T lymphocyte antigen 4) and PlGF-2123–144–anti–PD-L1 (programmed death ligand 1) Abs delayed tumor growth and prolonged survival compared to the unmodified Abs in genetically engineered murine tumor models of melanoma and breast cancer. The PlGF-2123–144–Abs increased tumor-infiltrating activated CD8+ and CD4+ T cells, resulting in a delay of distant tumor growth as well. This simple and translatable approach of engineered ECM-binding Abs may present a viable and safer approach in checkpoint blockade

Improving efficacy and safety of agonistic anti-CD40 antibody through extracellular matrix affinity

CD40 is an immune costimulatory receptor expressed by antigen-presenting cells. Agonistic anti-CD40 antibodies have demonstrated considerable antitumor effects yet can also elicit serious treatment-related adverse events, such as liver toxicity, including in man. We engineered a variant that binds extracellular matrix through a super-affinity peptide derived from placenta growth factor-2 (PlGF-2123-144) to enhance anti-CD40′s effects when administered locally. Peritumoral injection of PlGF-2123-144-anti-CD40 antibody showed prolonged tissue retention at the injection site and substantially decreased systemic exposure, resulting in decreased liver toxicity. In four mouse tumor models, PlGF-2123-144-anti-CD40 antibody demonstrated enhanced antitumor efficacy compared with its unmodified form and correlated with activated dendritic cells, B cells, and T cells in the tumor and in the tumor-draining lymph node. Moreover, in a genetically engineered BrafV600E βCatSTA melanoma model that does not respond to checkpoint inhibitors, PlGF-2123-144-anti-CD40 antibody treatment enhanced T-cell infiltration into the tumors and slowed tumor growth. Together, these results demonstrate the marked therapeutic advantages of engineering matrix-binding domains onto agonistic anti-CD40 antibody as a therapeutic given by tumori-regional injection for cancer immunotherapy

Recruitment of CD103+ dendritic cells via tumor-targeted chemokine delivery enhances efficacy of checkpoint inhibitor immunotherapy

Although a clinical breakthrough for cancer treatment, it remains that a minority of patients respond to checkpoint inhibitor (CPI) immunotherapy. The composition of tumor-infiltrating immune cells has been identified as a key factor influencing CPI therapy success. Thus, enhancing tumor immune cell infiltration is a critical challenge. A lack of the chemokine CCL4 within the tumor microenvironment leads to the absence of CD103+ dendritic cells (DCs), a crucial cell population influencing CPI responsiveness. Here, we use a tumor stroma–targeting approach to deliver CCL4; by generating a fusion protein of CCL4 and the collagen-binding domain (CBD) of von Willebrand factor, we show that CBD fusion enhances CCL4 tumor localization. Intravenous CBD-CCL4 administration recruits CD103+ DCs and CD8+ T cells and improves the antitumor effect of CPI immunotherapy in multiple tumor models, including poor responders to CPI. Thus, CBD-CCL4 holds clinical translational potential by enhancing efficacy of CPI immunotherapy

Collagen-binding IL-12 enhances tumour inflammation and drives the complete remission of established immunologically cold mouse tumours

Checkpoint-inhibitor (CPI) immunotherapy has achieved remarkable clinical success, yet its efficacy in ‘immunologically cold’ tumours has been modest. Interleukin-12 (IL-12) is a powerful cytokine that activates the innate and adaptive arms of the immune system; however, the administration of IL-12 has been associated with immune-related adverse events. Here we show that, after intravenous administration of a collagen-binding domain fused to IL-12 (CBD–IL-12) in mice bearing aggressive mouse tumours, CBD–IL-12 accumulates in the tumour stroma due to exposed collagen in the disordered tumour vasculature. In comparison with the administration of unmodified IL-12, CBD–IL-12 induced sustained intratumoural levels of interferon-γ, substantially reduced its systemic levels as well as organ damage and provided superior anticancer efficacy, eliciting complete regression of CPI-unresponsive breast tumours. Furthermore, CBD–IL-12 potently synergized with CPI to eradicate large established melanomas, induced antigen-specific immunological memory and controlled tumour growth in a genetically engineered mouse model of melanoma. CBD–IL-12 may potentiate CPI immunotherapy for immunologically cold tumours