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1.
Anal Chem ; 96(2): 802-809, 2024 01 16.
Article in English | MEDLINE | ID: mdl-38155586

ABSTRACT

The oral administration of protein therapeutics in solid dosage form is gaining popularity due to its benefits, such as improved medication adherence, convenience, and ease of use for patients compared to traditional parental delivery. However, formulating oral biologics presents challenges related to pH barriers, enzymatic breakdown, and poor bioavailability. Therefore, understanding the interaction between excipients and protein therapeutics in the solid state is crucial for formulation development. In this Letter, we present a case study focused on investigating the role of excipients in protein aggregation during the production of a solid dosage form of a single variable domain on a heavy chain (VHH) protein. We employed solid-state hydrogen-deuterium exchange coupled with mass spectrometry (ssHDX-MS) at both intact protein and peptide levels to assess differences in protein-excipient interactions between two formulations. ssHDX-MS analysis revealed that one formulation effectively prevents protein aggregation during compaction by blocking ß-sheets across the VHH protein, thereby preventing ß-sheet-ß-sheet interactions. Spatial aggregation propensity (SAP) mapping and cosolvent simulation from molecular dynamics (MD) simulation further validated the protein-excipient interaction sites identified through ssHDX-MS. Additionally, the MD simulation demonstrated that the interaction between the VHH protein and excipients involves hydrophilic interactions and/or hydrogen bonding. This novel approach holds significant potential for understanding protein-excipient interactions in the solid state and can guide the formulation and process development of orally delivered protein dosage forms, ultimately enhancing their efficacy and stability.


Subject(s)
Deuterium Exchange Measurement , Excipients , Humans , Deuterium/chemistry , Excipients/chemistry , Deuterium Exchange Measurement/methods , Molecular Dynamics Simulation , Protein Aggregates , Freeze Drying/methods , Proteins/chemistry , Hydrogen/chemistry , Mass Spectrometry/methods
2.
Mol Pharm ; 21(1): 325-332, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38060811

ABSTRACT

The oral delivery of protein therapeutics offers numerous advantages for patients but also presents significant challenges in terms of development. Currently, there is limited knowledge available regarding the stability and shelf life of orally delivered protein therapeutics. In this study, a comprehensive assessment of the stability of an orally delivered solid dosage variable domain of heavy-chain antibody (VHH antibody) drug product was conducted. Four stability related quality attributes that undergo change as a result of thermal and humidity stress were identified. Subsequently, these attributes were modeled using an accelerated stability approach facilitated by ASAPprime software. To the best of our knowledge, this is the first time that this approach has been reported for an antibody drug product. We observed overall good model quality and accurate predictions regarding the protein stability during storage. Notably, we discovered that protein aggregation, formed through a degradation pathway, requires additional adjustments to the modeling method. In summary, the ASAP approach demonstrated promising results in predicting the stability of this complex solid-state protein formulation. This study sheds light on the stability and shelf life of orally delivered protein therapeutics, addressing an important knowledge gap in the field.


Subject(s)
Antibodies , Humans , Drug Stability , Pharmaceutical Preparations , Protein Stability , Humidity
3.
Pediatr Blood Cancer ; 63(9): 1615-21, 2016 09.
Article in English | MEDLINE | ID: mdl-27203368

ABSTRACT

PURPOSE: This study aimed to estimate the burden of morbidity, in terms of health-related quality of life (HRQL), in survivors of high-risk neuroblastoma (NBL) after myeloablative chemotherapy followed by autologous hematopoietic stem cell transplant (HSCT). PATIENTS AND METHODS: A national population-based survey was undertaken of survivors of high-risk NBL (N = 99), diagnosed between 1991 and 2010 and treated with HSCT. Parents completed a proxy questionnaire incorporating two HRQL measures, Health Utilities Index (HUI) 2 and 3. Children >12 years of age provided self-assessments. Clinical and demographic data were collected. Independent t-test and one-way analysis of variance were used to assess differences. Comparative data were obtained from previously published work and Statistics Canada's 1998 National Population Health Survey. RESULTS: On a scale of 0 (being dead) to 1.0 (perfect health), mean HRQL utility scores were 0.89 (SD = 0.11) in HUI2 and 0.84 (SD = 0.18) in HUI3. Parents reported morbidity in sensation (52.5%), pain (30.3%), cognition (28.0%), and emotion (24.2%) in HUI2 and in hearing (38.4%), pain (30.3%), cognition (27.3%), and speech (23.2%) in HUI3. HRQL was not significantly different compared to NBL survivors treated without HSCT, but was less than in nontransplanted survivors of acute lymphoblastic leukemia and Wilms tumor, and children in the general population, yet higher than in survivors of brain tumors. CONCLUSIONS: HRQL is compromised in high-risk NBL survivors treated with and without HSCT. A differential effect on hearing reflects additional exposure to platinum-based chemotherapy. These results should inform long-term care and the development of new therapeutic interventions.


Subject(s)
Hematopoietic Stem Cell Transplantation , Neuroblastoma/psychology , Quality of Life , Survivors , Adolescent , Child , Child, Preschool , Cognition , Female , Hearing , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Infant , Male , Neuroblastoma/mortality , Neuroblastoma/therapy
4.
J Invest Dermatol ; 2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39084489

ABSTRACT

Hidradenitis suppurativa (HS) is a chronic inflammatory disease manifesting as painful dermal nodules, abscesses, and tunnels. Activation of the IL-1R/toll-like receptor pathway is strongly implicated in the pathogenesis of HS; thus, the role of a key signaling node, IRAK4, was investigated in a noninterventional study (NCT04440410) that enrolled 30 patients with HS. IRAK4 expression was evaluated in blood and lesional, perilesional, and nonlesional skin biopsies. PBMCs expressed IRAK4, with significantly higher levels in monocytes (P ≤ .0001). Ex vivo treatment of PBMCs with KT-474, a targeted degrader of IRAK4, robustly decreased IRAK4 in all immune cell types from healthy volunteers and patients with HS. Ex vivo treatment of toll-like receptor-stimulated healthy donor monocytes with KT-474 decreased IRAK4 protein levels and inhibited inflammatory cytokine production. In HS skin samples, IRAK4 protein levels were significantly higher in lesional than in nonlesional tissue (P ≤ .0001), and IRAK4-positive immune infiltrate increased with greater disease severity. Multiple inflammatory mediators were upregulated in HS lesional skin, correlating with IRAK4 overexpression. These data confirm the significance of the IL-1R/toll-like receptor pathway in the pathogenesis of HS and provide support for ongoing clinical studies evaluating KT-474 in the treatment of HS.

5.
ACS Appl Mater Interfaces ; 16(24): 31294-31303, 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38838350

ABSTRACT

Photodetector technology has evolved significantly over the years with the emergence of new active materials. However, there remain trade-offs between spectral sensitivity, operating energy, and, more recently, an ability to harbor additional features such as persistent photoconductivity and bidirectional photocurrents for new emerging application areas such as switchable light imaging and filter-less color discrimination. Here, we demonstrate a self-powered bidirectional photodetector based on molybdenum disulfide/gallium nitride (MoS2/GaN) epitaxial heterostructure. This fabricated detector exhibits self-powered functionality and achieves detection in two discrete wavelength bands: ultraviolet and visible. Notably, it attains a peak responsivity of 631 mAW-1 at a bias of 0V. The device's response to illumination at these two wavelengths is governed by distinct mechanisms, activated under applied bias conditions, thereby inducing a reversal in the polarity of the photocurrent. This work underscores the feasibility of self-powered and bidirectional photocurrent detection but also opens new vistas for technological advancements for future optoelectronic, neuromorphic, and sensing applications.

6.
Aging Cell ; 21(10): e13687, 2022 10.
Article in English | MEDLINE | ID: mdl-36073342

ABSTRACT

In humans, associative memories are more susceptible to age-related cognitive decline (ARCD) than are recognition memories. Reduced cAMP/cGMP signaling in the hippocampus may contribute to ARCD. Here, we found that both aging and traumatic brain injury-associated dementia increased the expression of the cAMP/cGMP-degrading enzyme phosphodiesterase 11A (PDE11A) in the human hippocampus. Further, age-related increases in hippocampal PDE11A4 mRNA and protein were conserved in mice, as was the increased vulnerability of associative versus recognition memories to ARCD. Interestingly, mouse PDE11A4 protein in the aged ventral hippocampus (VHIPP) ectopically accumulated in the membrane fraction and filamentous structures we term "ghost axons." These age-related increases in expression were driven by reduced exoribonuclease-mediated degradation of PDE11A mRNA and increased PDE11A4-pS117/pS124, the latter of which also drove the punctate accumulation of PDE11A4. In contrast, PDE11A4-pS162 caused dispersal. Importantly, preventing age-related increases in PDE11 expression via genetic deletion protected mice from ARCD of short-term and remote long-term associative memory (aLTM) in the social transmission of food preference assay, albeit at the expense of recent aLTM. Further, mimicking age-related overexpression of PDE11A4 in CA1 of old KO mice caused aging-like impairments in CREB function and remote social-but not non-social-LTMs. RNA sequencing and phosphoproteomic analyses of VHIPP identified cGMP-PKG-as opposed to cAMP-PKA-as well as circadian entrainment, glutamatergic/cholinergic synapses, calcium signaling, oxytocin, and retrograde endocannabinoid signaling as mechanisms by which PDE11A deletion protects against ARCD. Together, these data suggest that PDE11A4 proteinopathies acutely impair signaling in the aged brain and contribute to ARCD of social memories.


Subject(s)
3',5'-Cyclic-GMP Phosphodiesterases , Cognitive Dysfunction , 3',5'-Cyclic-GMP Phosphodiesterases/genetics , 3',5'-Cyclic-GMP Phosphodiesterases/metabolism , Aged , Animals , Cholinergic Agents/metabolism , Cognitive Dysfunction/metabolism , Endocannabinoids/metabolism , Exoribonucleases/metabolism , Hippocampus/metabolism , Humans , Mice , Oxytocin/metabolism , RNA, Messenger/metabolism
7.
Clin Immunol ; 131(2): 179-88, 2009 May.
Article in English | MEDLINE | ID: mdl-19217351

ABSTRACT

This FOCIS Centers of Excellence Short Analytical Review is based on the clinical vignette of two boys from the same family with very different outcomes following hematopoietic stem cell transplantation (HSCT) for X-linked severe combined immunodeficiency (SCID). We review the kinetics of immune reconstitution following HSCT in SCID and emphasize the latest information regarding optimizing transplant outcomes for this disorder. The cases illustrate the difficulties and controversies surrounding the optimal strategies for planning SCID transplants. Specifically, we will focus on 3 areas of current debate and investigation: (i) factors involved in donor selection; (ii) the role of pretransplant conditioning; and (iii) benefits of early HSCT for SCID.


Subject(s)
Hematopoietic Stem Cell Transplantation , X-Linked Combined Immunodeficiency Diseases/therapy , Fatal Outcome , Female , Humans , Infant, Newborn , Interleukin Receptor Common gamma Subunit/genetics , Male , Mutation , Pregnancy , Treatment Outcome
8.
Hum Nat ; 19(4): 426-52, 2008 Dec.
Article in English | MEDLINE | ID: mdl-26181751

ABSTRACT

Uncertainty exerts powerful influences on life history decisions. This has been demonstrated in experiments on nonhumans and in mathematical models. Studies of human populations are suggestive of the effects of uncertainty, but they rely on measures of environmental stress. In this paper, we derive a new measure of uncertainty, upsilon (υ), for use in non-experimental studies. We estimate its association with reproductive behaviors in a longitudinal panel sample of adolescents in the United States. Results show upsilon's internal structure is consistent with theoretical models of uncertainty. Its associations with reproductive outcomes are also consistent with theoretical predictions. Upsilon seems to have its largest effect on the timing of fertility-increasing the odds of early fertility by a factor of 7, net of the effects of control variables. We discuss our findings for the association between υ and the timing of reproductive effort as well as our future research on υ.

9.
JAMA ; 310(15): 1626, 2013 Oct 16.
Article in English | MEDLINE | ID: mdl-24129472
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