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Abstract Cryopreservation of blood-derived immune cells is commonly used in clinical trials to examine immunological responses. However, studies elucidating the effects of cryopreservation on peripheral blood mononuclear cell (PBMC) responses have shown inconsistent results making it difficult to draw meaningful conclusions. Therefore we sought to address this issue by comparing key innate and adaptive immune parameters between freshly-isolated and cryopreserved PBMCs from healthy adults. We examined the effect of cryopreservation on the expression of key markers on innate and adaptive immune cell populations (i.e. CD4+ and CD8+ [T cells], CD14+ [monocytes], CD19+ [B cells], CD56+ [NK cells] or CD19 + CD27+ [memory B cells]), on cytokine secretion (TNF-α, INF-γ, IL-1β, IL-10, IL-6, MCP-1 and RANTES) in cultured PBMC supernatants following stimulation with a range of Toll-like receptor (TLR) agonists, as well as on antigen-specific memory B cell enumeration by ELISpot. We found that cryopreservation had no effect on the expression of immune markers on innate and adaptive immune cells as well on the number of antigen-specific memory B cells. However, the response to TLR ligands such as FLA-ST, CpG and LPS was variable with increased cytokine production by cryopreserved PBMCs observed compared to freshly-isolated PBMCs. Our results suggest that the effect of cryopreservation on the biological response of immune cell populations needs to be carefully considered, particularly in the context of clinical studies that rely on these immune outcomes. Highlights • Cryopreservation of PBMCs have variable effects on innate and adaptive immune cell populations. • Cryopreserved PBMCs did not differ in the expression of key immune cell markers or antigen-specific B cell responses. • Cryopreservation led to increased cytokine and chemokine secretion for most TLR ligands examined. • These studies have important implications for clinical trials that rely on the use of cryopreserved PBMCs. [ABSTRACT FROM AUTHOR]

The article focuses on a study which assessed if R788, an orally bioavailable small molecule inhibitor of spleen tyrosine kinase (Syk)-dependent signaling, could modulate disease in lupus-prone mice by inhibiting Fc receptor (FcR) and B cell receptor signaling. R788 was administered to the mice before and after the onset of lupus. The study found that R788 delayed the onset of proteinuria and azotemia, reduced renal pathology and prolonged survival.

Pharmaceutical and agrochemical discovery programs are under considerable pressure to meet increasing global demand and thus require constant innovation. Classical hydrocarbon scaffolds have long assisted in bringing new molecules to the market place, but an obvious omission is that of the Platonic solid cubane. Eaton, however, suggested that this molecule has the potential to act as a benzene bioisostere. Herein, we report the validation of Eaton's hypothesis with cubane derivatives of five molecules that are used clinically or as agrochemicals. Two cubane analogues showed increased bioactivity compared to their benzene counterparts whereas two further analogues displayed equal bioactivity, and the fifth one demonstrated only partial efficacy. Ramifications from this study are best realized by reflecting on the number of bioactive molecules that contain a benzene ring. Substitution with the cubane scaffold where possible could revitalize these systems, and thus expedite much needed lead candidate identification. [ABSTRACT FROM AUTHOR]

Pharmaceutical and agrochemical discovery programs are under considerable pressure to meet increasing global demand and thus require constant innovation. Classical hydrocarbon scaffolds have long assisted in bringing new molecules to the market place, but an obvious omission is that of the Platonic solid cubane. Eaton, however, suggested that this molecule has the potential to act as a benzene bioisostere. Herein, we report the validation of Eaton's hypothesis with cubane derivatives of five molecules that are used clinically or as agrochemicals. Two cubane analogues showed increased bioactivity compared to their benzene counterparts whereas two further analogues displayed equal bioactivity, and the fifth one demonstrated only partial efficacy. Ramifications from this study are best realized by reflecting on the number of bioactive molecules that contain a benzene ring. Substitution with the cubane scaffold where possible could revitalize these systems, and thus expedite much needed lead candidate identification. [ABSTRACT FROM AUTHOR]

Hemopoietic stem cells (HSCs) are extrinsically controlled by the bone marrow (BM) microenvironment. Mice devoid of the extracellular matrix molecule Tenascin-C (TNC) were reported to develop normally. The current study explores the relationship between TNC and hemopoiesis, from HSCs within their niche to maturing progenitors in alternate niches. Although the absence of TNC did not alter the size of the BM stem cell pool, we report decreased thymic T cell progenitors with redistribution to other lymphoid organs, suggesting an anchoring role for TNC. TNC did not play an essential role in stem and progenitor cell homing to BM, but significantly altered lymphoid primed progenitor cell homing. These cells express the TNC receptor, integrin α 9β1, with the same reduced homing evident in the absence of this integrin. The absence of TNC also resulted in an increased proportion and number of mature circulating T cells. In addition, the absence of TNC significantly impaired hemopoietic reconstitution after transplant and increased stem and progenitor cell mobilization. In summary, our analysis revealed unidentified roles for TNC in hemopoiesis: in lineage commitment of thymic T cell progenitors, peripheral T cell migration, and hemopoietic reconstitution. [ABSTRACT FROM AUTHOR]

The activating mutations in JAK2 (including JAK2V617F) that have been described in patients with myeloproliferative neoplasms (MPNs) are linked directly to MPN pathogenesis. We developed R723, an orally bioavailable small molecule that inhibits JAK2 activity in vitro by 50% at a concentration of 2nM, while having minimal effects on JAK3, TYK2, and JAK1 activity. R723 inhibited cytokine-independent CFU-E growth and constitutive activation of STAT5 in primary hematopoietic cells expressing JAK2V617F. In an anemia mouse model induced by phenylhydrazine, R723 inhibited erythropoiesis. In a leukemia mouse model using Ba/F3 cells expressing JAK2V617F, R723 treatment prolonged survival and decreased tumor burden. In V617F-transgenic mice that closely mimic human primary myelofibrosis, R723 treatment improved survival, hepatosplenomegaly, leukocytosis, and thrombocytosis. R723 preferentially targeted the JAK2-dependent pathway rather than the JAK1- and JAK3-dependent pathways in vivo, and its effects on T and B lymphocytes were mild compared with its effects on myeloid cells. Our preclinical data indicate that R723 has a favorable safety profile and the potential to become an efficacious treatment for patients with JAK2V617F-positive MPNs. [ABSTRACT FROM AUTHOR]

Bioisosterie In ihrer Zuschrift auf S. 3644 ff. bestätigen C. M. Williams, G. P. Savage, J. Tsanaktsidis et al. durch die Synthese und Evaluierung von Cuban‐Derivaten fünf biologisch wichtiger Verbindungen, dass Cuban und Benzol bioisoster sind. [ABSTRACT FROM AUTHOR]

The cover page of the journal “Angewandte Chemie" is presented.