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Biology subjects

Hubbard, G.

Publications and source records attributed to Hubbard, G..

3 recordsLinked to original sources

Biosynthetic additive manufacturing through mycelium-bacteria consortia

Lignocellulosic biomass is the most abundant renewable raw material on Earth, yet its structural and carbon-storage potential remains unrealized: microbial decomposition returns stored carbon to the atmosphere before it can be harnessed as a durable material. Distinct microbial processes, such as biosynthesis and biomineralization, offer a natural counterpoint, converting organic carbon into mechanically robust, persistent materials such as polymers and minerals. Here, we establish a biosynthetic additive manufacturing strategy through mycelium-bacteria consortia, by coupling fungal self-assembly with bacterial biomineralization inside fabricated three-dimensional scaffolds derived from lignocellulosic biomass. Trametes versicolor forms a continuous living mycelial network that serves as both a structural template and a transport pathway, guiding the spatial colonization of Sporosarcina pasteurii and enabling volumetric calcium carbonate deposition throughout the scaffold interior, overcoming the surface-limited mineralization of conventional microbial systems. Integration with helicoidal Bouligand architectures translates microscale mineral reinforcement into macroscale performance, increasing compressive Young's modulus by 7-14-fold and ultimate strength by 5-fold relative to unmineralized conventional mycelium-based living composites. The living mycelial network also enables autonomous self-healing and modular self-assembly through hyphal bridging without external adhesives or energy input. This work establishes a scalable route for converting and upcycling transient biomass carbon into durable living structural materials for sustainable construction.

bioengineering↗

PDL1 CHECKPOINT BLOCKADE SYNERGIZES WITH NILOTINIB BUT NOT DASATINIB TO PREVENT LEUKEMIA RELAPSE

Dasatinib and nilotinib are front line Tyrosine Kinase Inhibitors (TKIs) used to treat BCR-ABL+ B cell acute lymphoblastic leukemia (B-ALL) and BCR-ABL+ chronic myelogenous leukemia. We previously showed that combining nilotinib with anti-PD-L1 blockade significantly reduced leukemia relapse. The TKI dasatinib is more commonly used to treat to B-ALL. However, unlike nilotinib, dasatinib also inhibits SRC-family kinases, which may make it less efficacious in combination with anti-PDL1 blockade. Herein we assess the impact of nilotinib versus dasatinib on anti-leukemia immune responses. Dasatinib, but not nilotinib, inhibited T cell proliferation at high doses in-vitro, but neither TKI significantly impacted T cell function or expansion in response to immunization in-vivo with a model antigen (2W1S) plus polyIC-adjuvant. Dasatinib and nilotinib both reduced leukemic blasts equivalently after 5 days of treatment. In contrast, nilotinib and PD-L1 blockade, but not dasatinib plus anti-PDL1, prevented relapse several weeks later. Thus, dasatinib negatively impacts protective anti-leukemia T cell responses that prevent leukemia relapse.

immunology↗

Identification of mutations that cooperate with defects in B cell transcription factors to initiate leukemia

The transcription factors EBF1 and PAX5 are frequently mutated in B cell acute lymphoblastic leukemia (B-ALL). We demonstrate that Pax5+/- x Ebf1+/- compound heterozygous mice develop highly penetrant leukemia. Similar results were seen in Pax5+/- x Ikzf1+/- and Ebf1+/- x Ikzf1+/- mice for B-ALL, or in Tcf7+/- x Ikzf1+/- mice for T cell leukemia. To identify genetic defects that cooperate with Pax5 and Ebf1 compound heterozygosity to initiate leukemia, we performed a Sleeping Beauty (SB) transposon screen that identified cooperating partners including gain-of-function mutations in Stat5 ([~]65%) and Jak1([~]68%), or loss-of-function mutations in Cblb (61%) and Myb (32%). These findings underscore the role of JAK/STAT5 signaling in B cell transformation and demonstrate unexpected roles for loss-of-function mutations in Cblb and Myb in leukemic transformation. RNA-Seq studies demonstrated upregulation of a PDK1>SGK3>MYC pathway; treatment of Pax5+/- x Ebf1+/- leukemia cells with PDK1 inhibitors blocked proliferation in vitro. Finally, we identified conserved transcriptional variation in a subset of genes between human leukemias and our mouse B-ALL models. Thus, compound haploinsufficiency for B cell transcription factors likely plays a critical role in transformation of human B cells and suggest that PDK1 inhibitors may be effective for treating patients with such defects.

cancer biology↗