Determining the Impact of Callosal Connectivity on Visual Acuity and Cortical Visual Impairment in CDKL5 Deficiency Disorder

Authors:

Mia Schenenga, Elyza Kelly, Michela Fagiolini

Date Created:

2025-01-01

Course Title:

Professor:

Not specified

About Paper:

Approximately 75% of individuals with CDKL5 Deficiency followed by intraperitoneal injection of clozapine N-oxide. We Disorder (CDD), a developmental epileptic encephalopathy, then assessed visual acuity via visual-evoked potential (VEP) experience cortical visual impairment (CVI), occurring when recording. We found that CPN inhibition significantly rescued visual dysfunction cannot be explained by deficits in the eyes visual acuity in CDKL5-deficient mice, supporting our hypothesis alone. We do not yet understand the underlying circuitry, and of excess callosal connectivity. To better understand the no effective treatments exist. CVI is reflected in CDKL5- increased functional connectivity via the corpus callosum, we deficient mouse models by a reduced response in the visual examined CPN synaptic connectivity via Vglut1 and PSD-95 cortex (VC) to visual stimulus and reduced visual acuity. Given staining, expecting an increased number of excitatory synapses. that connectivity between hemispheres is critical for vision, we However, preliminary results indicate that CDKL5-deficient mice examined connectivity of the corpus callosum and observed that demonstrate a reduced number of excitatory synapses, but an these mice display increased interhemispheric synchronization and increased number of parvalbumin (PV) neurons, a key inhibitory functionalconnectivityacrosscorticalhemispheres, despitehaving interneuron, in the VC. This suggests that CDKL5-deficient mice no change in the number of callosal projection neurons (CPNs). have an increased proportion of CPN synapses onto inhibitory This suggests that increased callosal connectivity contributes to interneuronsin theVC, whichmay bethe mechanismforincreased reduced visual acuity in CDKL5-deficient mice. synchronization between hemispheres. Our ongoing study aims to determine whether altered CPN-PV connectivity underlies To determine if excess callosal connectivity impacts visual acuity,reduced visual acuity in CDKL5-deficient mice, elucidating the we inhibited CPNs in Satb2-cre-positive CDKL5-deficient mice by injection of a cre-dependent DREADDs virus in the VC circuitry underlying CVI in CDD and guiding future therapeutic development. Unbiased Discovery of Bispecific T-cell Activating Antibodies across Multiple Cancer Subtypes Matheus Silva, Juliano Ribeiro, Kipp Weiskopf Harvard College | Adams House | Biomedical Engineering | 2027 Cancer immunotherapy focused on T lymphocytes has bsAbs. revolutionized oncologic treatment, with strategies including We expanded and optimized this platform for solid tumors chimeric antigen receptor (CAR) T-cell therapy, checkpoint conducting diluted combinatorial co-cultures with different blockade, and cancer vaccinology. Among newer strategies, CD3 bispecific antibodies (bsAbs) are two distinct single-chain variableffector-to-target ratios of T-cells (at 20k, 10k, 2k, or 1k), cancer fragments (scFvs), derived from the antigen-binding domains of cells (at 10k, 5k, 2k, or 1k), and epicoritumab (at 10, 1, or 0 µg/mL). Through this adapted platform, we engineered bispecifics anti-CD3 and anti-tumor-associated antigen antibodies, covalently combining EGFR, HER2, and CD20 cancer targets with CD3ε, connected by small linker peptides. Despite demonstrating LILRB1, and PD-L1 T-cell targets, testing for format (linker vs. significant clinical success in hematologic malignancies, there non-linker), concentration, function, and binding strength across remains a need to discover new CD3 bsAbs for additional targets and tumor types. gastric, lymphoma, colorectal, lung, and myeloma co-cultures. This study expands on a high-throughput functional screening To harness the effects of T-cells and create new therapies, the Weiskopf Lab developed a high-throughput platform to rapidly assaytorevealoptimalconditionsforlong-termT-cellengagement engineer, produce, and evaluate novel CD3-engagers. These analysis in solid cancers and identifies promising therapeutic targets. Further validation in organoid and humanized mouse antibodies were formatted into scFvs and then fused to a human models will follow, where success will lead to a larger IgG1 knob or hole Fc construct, permitting rapid combinatorial combinatorial screening of cancer targets and cell lines, prompting production and screening. To assess their function, we employed a microscopy-based co-culture assay to measure the long-term an even broader investigation of bsAb combination therapies for elimination of cancer cells by T-cells and the unique scFv-Fc heterogeneous solid tumors. 126 Program for Research in Science and Engineering A Structural MRI-Guided Approach to Theta Burst Stimulation: Evaluating Changes in Resting-State Connectivity Marcus Smith, Shuqing Deng, Ovidiu Andronesi Harvard College | Quincy House | Neuroscience | 2028 Theta burst stimulation (TBS) is a non-invasive form of anatomical and rs-fMRI scans were collected to examine changes transcranial magnetic stimulation (TMS) that uses patterned in functional connectivity before and after TBS. This data was magnetic pulses to stimulate activity inside the brain. TBS processed using a custom analysis pipeline with which we aim to is widely used in clinical and research settings, however, determine whether anatomically guided TBS leads to a measurable there still remains questions about how to most effectively change in resting-state brain activation. When comparing the rs- deliver stimulation via TBS. In addition, TBS’s effect on neural fMRI scans, we expect to observe an uptick in neural activity functionally has never been completely understood. This study in the specific regions where TBS was administered. We also aims to use high-resolution structural magnetic resonance imaging expect to observe no significant changes in non-selected regions (MRI) imaging to guide targeted TBS signals to the brain and of the brain, hinting at targeted stimulation, instead of whole brain evaluate the effectiveness of this approach in terms of functional functionalitychanges. Iftheseexpectationsholdtrue,targetedTBS changes. To examine this, we first collected baseline anatomical may help create a framework for future treatment which utilizes and resting-state functional MRI (rs-fMRI) scans prior to TBS. an individual’s neuroanatomy for specialized neuromodulation Then we used structural data to identify TBS target sites in therapy. These findings may also inform future research on the motor cortex and administered treatment to those regions the functional and neural changes involved in personalized TMS of interest, and following this treatment period, post-treatment strategies and

Abstract:

Approximately 75% of individuals with CDKL5 Deficiency followed by intraperitoneal injection of clozapine N-oxide. We Disorder (CDD), a developmental epileptic encephalopathy, then assessed visual acuity via visual-evoked potential (VEP) experience cortical visual impairment (CVI), occurring when recording. We found that CPN inhibition significantly rescued visual dysfunction cannot be explained by deficits in the eyes visual acuity in CDKL5-deficient mice, supporting our hypothesis alone. We do not yet understand the underlying circuitry, and of excess callosal connectivity. To better understand the no effective treatments exist. CVI is reflected in CDKL5- increased functional connectivity via the corpus callosum, we deficient mouse models by a reduced response in the visual examined CPN synaptic connectivity via Vglut1 and PSD-95 cortex (VC) to visual stimulus and reduced visual acuity. Given staining, expecting an increased number of excitatory synapses. that connectivity between hemispheres is critical for vision, we However, preliminary results indicate that CDKL5-deficient mice examined connectivity of the corpus callosum and observed that demonstrate a reduced number of excitatory synapses, but an these mice display increased interhemispheric synchronization and increased number of parvalbumin (PV) neurons, a key inhibitory functionalconnectivityacrosscorticalhemispheres, despitehaving interneuron, in the VC. This suggests that CDKL5-deficient mice no change in the number of callosal projection neurons (CPNs). have an increased proportion of CPN synapses onto inhibitory This suggests that increased callosal connectivity contributes to interneuronsin theVC, whichmay bethe mechanismforincreased reduced visual acuity in CDKL5-deficient mice. synchronization between hemispheres. Our ongoing study aims to determine whether altered CPN-PV connectivity underlies To determine if excess callosal connectivity impacts visual acuity,reduced visual acuity in CDKL5-deficient mice, elucidating the we inhibited CPNs in Satb2-cre-positive CDKL5-deficient mice by injection of a cre-dependent DREADDs virus in the VC circuitry underlying CVI in CDD and guiding future therapeutic development. Unbiased Discovery of Bispecific T-cell Activating Antibodies across Multiple Cancer Subtypes Matheus Silva, Juliano Ribeiro, Kipp Weiskopf Harvard College | Adams House | Biomedical Engineering | 2027 Cancer immunotherapy focused on T lymphocytes has bsAbs. revolutionized oncologic treatment, with strategies including We expanded and optimized this platform for solid tumors chimeric antigen receptor (CAR) T-cell therapy, checkpoint conducting diluted combinatorial co-cultures with different blockade, and cancer vaccinology. Among newer strategies, CD3 bispecific antibodies (bsAbs) are two distinct single-chain variableffector-to-target ratios of T-cells (at 20k, 10k, 2k, or 1k), cancer fragments (scFvs), derived from the antigen-binding domains of cells (at 10k, 5k, 2k, or 1k), and epicoritumab (at 10, 1, or 0 µg/mL). Through this adapted platform, we engineered bispecifics anti-CD3 and anti-tumor-associated antigen antibodies, covalently combining EGFR, HER2, and CD20 cancer targets with CD3ε, connected by small linker peptides. Despite demonstrating LILRB1, and PD-L1 T-cell targets, testing for format (linker vs. significant clinical success in hematologic malignancies, there non-linker), concentration, function, and binding strength across remains a need to discover new CD3 bsAbs for additional targets and tumor types. gastric, lymphoma, colorectal, lung, and myeloma co-cultures. This study expands on a high-throughput functional screening To harness the effects of T-cells and create new therapies, the Weiskopf Lab developed a high-throughput platform to rapidly assaytorevealoptimalconditionsforlong-termT-cellengagement engineer, produce, and evaluate novel CD3-engagers. These analysis in solid cancers and identifies promising therapeutic targets. Further validation in organoid and humanized mouse antibodies were formatted into scFvs and then fused to a human models will follow, where success will lead to a larger IgG1 knob or hole Fc construct, permitting rapid combinatorial combinatorial screening of cancer targets and cell lines, prompting production and screening. To assess their function, we employed a microscopy-based co-culture assay to measure the long-term an even broader investigation of bsAb combination therapies for elimination of cancer cells by T-cells and the unique scFv-Fc heterogeneous solid tumors. 126 Program for Research in Science and Engineering A Structural MRI-Guided Approach to Theta Burst Stimulation: Evaluating Changes in Resting-State Connectivity Marcus Smith, Shuqing Deng, Ovidiu Andronesi Harvard College | Quincy House | Neuroscience | 2028 Theta burst stimulation (TBS) is a non-invasive form of anatomical and rs-fMRI scans were collected to examine changes transcranial magnetic stimulation (TMS) that uses patterned in functional connectivity before and after TBS. This data was magnetic pulses to stimulate activity inside the brain. TBS processed using a custom analysis pipeline with which we aim to is widely used in clinical and research settings, however, determine whether anatomically guided TBS leads to a measurable there still remains questions about how to most effectively change in resting-state brain activation. When comparing the rs- deliver stimulation via TBS. In addition, TBS’s effect on neural fMRI scans, we expect to observe an uptick in neural activity functionally has never been completely understood. This study in the specific regions where TBS was administered. We also aims to use high-resolution structural magnetic resonance imaging expect to observe no significant changes in non-selected regions (MRI) imaging to guide targeted TBS signals to the brain and of the brain, hinting at targeted stimulation, instead of whole brain evaluate the effectiveness of this approach in terms of functional functionalitychanges. Iftheseexpectationsholdtrue,targetedTBS changes. To examine this, we first collected baseline anatomical may help create a framework for future treatment which utilizes and resting-state functional MRI (rs-fMRI) scans prior to TBS. an individual’s neuroanatomy for specialized neuromodulation Then we used structural data to identify TBS target sites in therapy. These findings may also inform future research on the motor cortex and administered treatment to those regions the functional and neural changes involved in personalized TMS of interest, and following this treatment period, post-treatment strategies and

Source:

Harvard / Nayan Sapers, Felix Radford, George Church / 2025

Topics:

visual, connectivity, tbs, cdkl5, cancer, acuity, mice, change, increased, functional, target, callosal

Co-authors:

@miaschenenga367 , @elyzakelly368 , @michelafagiolini369