Central to systemic lupus erythematosus (SLE) is the dysfunction of immune cells called B cells, leading to abnormal immune responses and the production of autoantibodies that mistakenly target the body’s own tissues. While corticosteroids are effective in controlling inflammation in SLE, they come with significant side effects, such as increased risk of infections and other health issues. There is a need for more targeted and safer treatments. Dr. Pishesha aims to develop a new type of therapy that engineers nanobodies – small fragments of traditional antibodies – to deliver anti-inflammatory drugs directly to specific immune cells.

Dr. Pishesha will create and test nanobody-dexamethasone (a corticosteroid) conjugates that can target specific immune cells in mouse models of lupus. She will track the distribution and effectiveness of these nanobodies using imaging and molecular techniques and assess their impact on lupus symptoms, including organ disease and immune cell responses. She will enhance these nanobody-based strategies by combining them with other treatments, such as Toll-like Receptor 7 (TLR7) antagonists (molecules that block TLR7, which is often elevated in SLE) to improve their effectiveness. She will also test the combined treatments on immune cells from both mouse models and cells from people with lupus.

What this means for people with lupus

Dr. Pishesha’s research could lead to new, more precise treatments for lupus, and reduce side effects associated with corticosteroids. By targeting specific immune cells, these nanobody-based therapies could improve patient outcomes, making treatment safer and more effective.

Systemic Lupus Erythematosus (SLE) is characterized by widespread inflammation and autoimmunity, often with severe complications and a dependency on immunosuppressants such as corticosteroids that are associated with significant side effects, especially in children. This proposal outlines a novel strategy that uses camelid-derived variable heavy domain of heavy-chain-only antibodies (VHHs/nanobodies) to deliver corticosteroids and other anti-inflammatory drugs directly to specific immune cell subsets. In this manner I expect to enhance precision of treatment and minimize adverse effects. This method ensures the release of antiinflammatory drugs only after internalization into endosomal compartments. It thus achieves targeted delivery directly to the affected cells and reduces the required dosage and frequency of administration. Such targeted therapy is expected to decrease systemic side effects and improve patient outcomes.

By leveraging our expertise in nanobody engineering, this project focuses on a reduction of systemic inflammation without broad suppression of the immune system. We plan to evaluate the biodistribution and therapeutic efficacy of VHH-drug conjugates in lupus mouse models (pristane-induced lupus and MRL/lpr mice), using advanced imaging and molecular techniques to assess their impact on immune cells. Our approach involves the development of a suite of nanobody-dexamethasone (VHH-DEX) conjugates targeted to key immune cells. These include anti-MHCII VHH (macrophages, dendritic cells, and B cells), anti-Ly6G VHH (mostly neutrophils), anti-CD11b VHH (macrophages and other myeloid cells), and anti-CD11c VHH (dendritic cells). In Aim 1, we will track the biodistribution of these engineered VHHs and evaluate their effectiveness at improving the clinical manifestations of lupus and associated immunological features, to identify the most effective preparations for delivery of DEX. Aim 2 seeks to broaden this strategy by develop multifunctional VHH conjugates that carry multiple drugs, including multiple DEX molecules and DEX in combination with TLR7 antagonists. Using multiparameter flow cytometry, ELISA, quantitative PCR (qPCR), and RNA sequencing, we will evaluate the impact of these conjugates on immune cells from lupus-prone mice in vitro as well as on human samples from lupus patients. These methods will provide insights into the effects of the conjugates on immune cell function, cytokine production, gene expression, and overall cellular response. This project is designed to establish a more sustainable and less harmful strategy to manage SLE to improving quality of life through a reduction of drug dosages and minimization of corticosteroid use. The implications for other autoimmune diseases are clear.