ABSTRACT CCR1, CCR2 and CCR5 direct recruitment of monocytes and macrophages in inflammation. However, the discrete role for each receptor in monocyte/macrophage biology remains poorly understood, with previous reports citing receptor redundancy. Using transcriptomic approaches to examine inflammatory chemokine receptor expression on lung interstitial macrophage populations, we demonstrate that interstitial macrophages can be divided into three distinct subsets, each of which express specific patterns of chemokine receptors, and that there are dynamic changes in chemokine receptor expression as macrophages differentiate from monocytes in the lung. Furthermore, macrophages expressing different combinations of chemokine receptors are transcriptionally distinct, suggesting non-redundant functions for CCR1, 2 and 5. Finally, we examined changes in macrophage chemokine receptor expression in vitro after treatment with varied TLR ligands, and show that CCR1 is specifically increased in response to bacterial but not viral ligands. Our data provide compelling evidence that macrophage chemokine receptor expression is not redundant, but specific and malleable in response to discrete inflammatory stimuli.

Subunits of the SWI/SNF chromatin remodeling complex are altered in ∼20% of human cancers. Exemplifying the alterations is the ARID1A mutation that occurs in ∼50% of ovarian clear-cell carcinoma (OCCC), a disease with limited therapeutic options. In this study, we showed that ARID1A mutations create a dependence on alanine by regulating alanine transporters to increase intracellular alanine levels. ARID1A directly repressed the alanine importer SLC38A2 and simultaneously promoted the alanine exporter SLC7A8. ARID1A inactivation increased alanine utilization predominantly in protein synthesis and passively through the tricarboxylic acid cycle. Indeed, ARID1A-mutant OCCCs were hypersensitive to the inhibition of SLC38A2. In addition, SLC38A2 inhibition enhanced chimeric antigen receptor T-cell assault in vitro and synergized with immune checkpoint blockade using an anti-PD-L1 antibody in a genetically engineered mouse model of OCCC driven by conditional Arid1a inactivation in a CD8+ T-cell-dependent manner. These findings suggest that targeting alanine transport alone or in combination with immunotherapy may represent an effective therapeutic strategy for ARID1A-mutant cancers.
ARID1A mutations regulate expression of alanine transporters to control alanine distribution between cancer cells and the associated tumor microenvironment, which may be exploited therapeutically alone or in combination with immunotherapy.
©2025 American Association for Cancer Research.

Impairment of oligodendrocytes and myelin contributes to neurological disorders including multiple sclerosis (MS), stroke, and Alzheimer's disease. Regeneration of myelin (remyelination) decreases the vulnerability of demyelinated axons, but this repair process commonly fails with disease progression. A contributor to inefficient remyelination is the altered extracellular matrix (ECM) in lesions, which remains to be better defined. We have identified fibulin-2 (FBLN2) as a highly upregulated ECM component in lesions of MS and stroke and in proteome databases of Alzheimer's disease and traumatic brain injury. Focusing on MS, the inhibitory role of FBLN2 was suggested in the experimental autoimmune encephalomyelitis (EAE) model, in which genetic FBLN2 deficiency improved behavioral recovery by promoting the maturation of oligodendrocytes and enhancing remyelination. Mechanistically, when oligodendrocyte progenitors were cultured in differentiation medium, FBLN2 impeded their maturation into oligodendrocytes by engaging the Notch pathway, leading to cell death. Adeno-associated virus deletion of FBLN2 in astrocytes improved oligodendrocyte numbers and functional recovery in EAE and generated new myelin profiles after lysolecithin-induced demyelination. Collectively, our findings implicate FBLN2 as a hitherto unrecognized injury-elevated ECM, and a therapeutic target, that impairs oligodendrocyte maturation and myelin repair.

Many vaccines, including those using recombinant antigen subunits, rely on adjuvant(s) to enhance the efficacy of the host immune responses. Among the few adjuvants clinically approved, QS-21, a saponin-based immunomodulatory molecule isolated from the tree bark of Quillaja saponaria (QS) is used in complex formulations in approved effective vaccines. High demand of the QS raw material as well as manufacturing scalability limitation has been barriers here. We report for the first-time successful plant cell culture production of QS-21 having structural, chemical, and biologic, properties similar to the bark extracted product. These data ensure QS-21 and related saponins are broadly available and accessible to drug developers.
© 2024 The Author(s).