Uniting education, research, healthcare, and society to advance women's heart health.

Complex health challenges require professionals to operate across disciplines and to better connect with society. Here, we showcase a community-engaged and challenge-based educational model in which undergraduate students conduct transdisciplinary research on authentic complex biomedical problems. This concept reinforces translational medicine, human capital, and exemplifies synergy between education, research, healthcare, and society.

A challenge-based interdisciplinary undergraduate concept fostering translational medicine.

Translational medicine (TM) is an interdisciplinary branch of biomedicine that bridges the gap from bench-to-bedside to improve global health. Fundamental TM skills include interdisciplinary collaboration, communication, critical thinking, and creative problem-solving (4Cs). TM is currently limited in undergraduate biomedical education programs, with little patient contact and opportunities for collaboration between different disciplines.

Cellular immunotherapy for medulloblastoma.

Medulloblastoma (MB) is the most common malignant brain tumor in children, making up ~20% of all primary pediatric brain tumors. Current therapies consist of maximal surgical resection and aggressive radio- and chemotherapy. A third of the treated patients cannot be cured and survivors are often left with devastating long-term side effects.

Immunotherapy in Medulloblastoma: Current State of Research, Challenges, and Future Perspectives.

Medulloblastoma (MB), a primary tumor of the central nervous system, is among the most prevalent pediatric neoplasms. The median age of diagnosis is six. Conventional therapies include surgical resection of the tumor with subsequent radiation and chemotherapy.

Noncytotoxic functions of killer cell granzymes in viral infections.

Cytotoxic lymphocytes produce granules armed with a set of 5 serine proteases (granzymes (Gzms)), which, together with the pore-forming protein (perforin), serve as a major defense against viral infections in humans. This granule-exocytosis pathway subsumes a well-established mechanism in which target cell death is induced upon perforin-mediated entry of Gzms and subsequent activation of various (apoptosis) pathways. In the past decade, however, a growing body of evidence demonstrated that Gzms also inhibit viral replication and potential reactivation in cell death-independent manners.

The selection of variable regions affects effector mechanisms of IgA antibodies against CD20.

Blockade of the CD47-SIRPα axis improves lymphoma cell killing by myeloid effector cells, which is an important effector mechanism for CD20 antibodies in vivo. The approved CD20 antibodies rituximab, ofatumumab, and obinutuzumab are of human immunoglobulin G1 (IgG1) isotype. We investigated the impact of the variable regions of these 3 CD20 antibodies when expressed as human IgA2 isotype variants.

A novel undergraduate biomedical laboratory course concept in synergy with ongoing faculty research.

Optimal integration of education and ongoing faculty research in many undergraduate science programs is limited to the capstone project. Here, we aimed to develop a novel course-based undergraduate research experience (CURE) in synergy with ongoing faculty research. This 10-week course called Biomedical Research Lab is embedded in the curriculum of the undergraduate program Biomedical Sciences and grounded in the theoretical framework of research-based learning.

Intracellular and Extracellular Roles of Granzyme K.

Granzymes are a family of serine proteases stored in granules inside cytotoxic cells of the immune system. Granzyme K (GrK) has been only limitedly characterized and knowledge on its molecular functions is emerging. Traditionally GrK is described as a granule-secreted, pro-apoptotic serine protease.

Bivalent binding on cells varies between anti-CD20 antibodies and is dose-dependent.

Based on their mechanism of action, two types of anti-CD20 antibodies are distinguished: Type I, which efficiently mediate complement-dependent cytotoxicity, and Type II, which instead are more efficient in inducing direct cell death. Several molecular characteristics of these antibodies have been suggested to underlie these different biological functions, one of these being the manner of binding to CD20 expressed on malignant B cells. However, the exact binding model on cells is unclear.

Novel chimerized IgA CD20 antibodies: Improving neutrophil activation against CD20-positive malignancies.

Current combination therapies elicit high response rates in B cell malignancies, often using CD20 antibodies as the backbone of therapy. However, many patients eventually relapse or develop progressive disease. Therefore, novel CD20 antibodies combining multiple effector mechanisms were generated.

IgA-Mediated Killing of Tumor Cells by Neutrophils Is Enhanced by CD47-SIRPα Checkpoint Inhibition.

Therapeutic monoclonal antibodies (mAb), directed toward either tumor antigens or inhibitory checkpoints on immune cells, are effective in cancer therapy. Increasing evidence suggests that the therapeutic efficacy of these tumor antigen-targeting mAbs is mediated-at least partially-by myeloid effector cells, which are controlled by the innate immune-checkpoint interaction between CD47 and SIRPα. We and others have previously demonstrated that inhibiting CD47-SIRPα interactions can substantially potentiate antibody-dependent cellular phagocytosis and cytotoxicity of tumor cells by IgG antibodies both and IgA antibodies are superior in killing cancer cells by neutrophils compared with IgG antibodies with the same variable regions, but the impact of CD47-SIRPα on IgA-mediated killing has not been investigated.

Potent Fc Receptor Signaling by IgA Leads to Superior Killing of Cancer Cells by Neutrophils Compared to IgG.

Antibody therapy of cancer is increasingly used in the clinic and has improved patient's life expectancy. Except for immune checkpoint inhibition, the mode of action of many antibodies is to recognize overexpressed or specific tumor antigens and initiate either direct F(ab')-mediated tumor cell killing, or Fc-mediated effects such as complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity/phagocytosis (ADCC/P) after binding to activating Fc receptors. All antibodies used in the clinic are of the IgG isotype.

FcαRI Dynamics Are Regulated by GSK-3 and PKCζ During Cytokine Mediated Inside-Out Signaling.

IgA binding to FcαRI (CD89) is rapidly enhanced by cytokine induced inside-out signaling. Dephosphorylation of serine 263 in the intracellular tail of FcαRI by PP2A and PI3K activation are instrumental in this process. To further investigate these signaling pathways, we targeted downstream kinases of PI3K.

Mechanisms of inside-out signaling of the high-affinity IgG receptor FcγRI.

Fc receptors (FcRs) are an important bridge between the innate and adaptive immune system. Fc gamma receptor I (FcγRI; CD64), the high-affinity receptor for immunoglobulin G (IgG), plays roles in inflammation, autoimmune responses, and immunotherapy. Stimulation of myeloid cells with cytokines, such as tumor necrosis factor-α ( TNFα) and interferon-γ ( IFNγ), increases the binding of FcγRI to immune complexes (ICs), such as antibody-opsonized pathogens or tumor cells, through a process known as "inside-out" signaling.

New insights in Type I and II CD20 antibody mechanisms-of-action with a panel of novel CD20 antibodies.

Based on their mechanisms-of-action, CD20 monoclonal antibodies (mAbs) are grouped into Type I [complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC)] and Type II [programmed cell death (PCD) and ADCC] mAbs. We generated 17 new hybridomas producing CD20 mAbs of different isotypes and determined unique heavy and light chain sequence pairs for 13 of them. We studied their epitope binding, binding kinetics and structural properties and investigated their predictive value for effector functions, i.

Single Nucleotide Polymorphisms of the High Affinity IgG Receptor FcγRI Reduce Immune Complex Binding and Downstream Effector Functions.

Binding of IgG Abs to FcγRs on immune cells induces FcγR cross-linking that leads to cellular effector functions, such as phagocytosis, Ab-dependent cellular cytotoxicity, and cytokine release. However, polymorphisms in low affinity FcγRs have been associated with altered avidity toward IgG, thereby substantially impacting clinical outcomes of multimodular therapy when targeting cancer or autoimmune diseases with mAbs as well as the frequency and severity of autoimmune diseases. In this context, we investigated the consequences of three nonsynonymous single nucleotide polymorphisms (SNPs) for the high affinity receptor for IgG, FcγRI.

Fc receptor inside-out signaling and possible impact on antibody therapy.

Fc receptors (FcR) are expressed on immune cells and bind to the Fc tail of antibodies. This interaction is essential for FcR-mediated signaling and triggering of cellular effector functions. FcR activation is tightly regulated to prevent immune responses by non-antigen bound antibodies or in the absence of 'danger signals'.

Simultaneous Targeting of FcγRs and FcαRI Enhances Tumor Cell Killing.

Efficacy of anticancer monoclonal antibodies (mAb) is limited by the exhaustion of effector mechanisms. IgG mAbs mediate cellular effector functions through FcγRs expressed on effector cells. IgA mAbs can also induce efficient tumor killing both in vitro and in vivo.

MHC class II antigen presentation by dendritic cells regulated through endosomal sorting.

For the initiation of adaptive immune responses, dendritic cells present antigenic peptides in association with major histocompatibility complex class II (MHCII) to naïve CD4(+) T lymphocytes. In this review, we discuss how antigen presentation is regulated through intracellular processing and trafficking of MHCII. Newly synthesized MHCII is chaperoned by the invariant chain to endosomes, where peptides from endocytosed pathogens can bind.

Endosome-mediated autophagy: an unconventional MIIC-driven autophagic pathway operational in dendritic cells.

Activation of TLR signaling has been shown to induce autophagy in antigen-presenting cells (APCs). Using high-resolution microscopy approaches, we show that in LPS-stimulated dendritic cells (DCs), autophagosomes emerge from MHC class II compartments (MIICs) and harbor both the molecular machinery for antigen processing and the autophagosome markers LC3 and ATG16L1. This ENdosome-Mediated Autophagy (ENMA) appears to be the major type of autophagy in DCs, as similar structures were observed upon established autophagy-inducing conditions (nutrient deprivation, rapamycin) and under basal conditions in the presence of bafilomycin A1.

Endosomally stored MHC class II does not contribute to antigen presentation by dendritic cells at inflammatory conditions.

Major histocompatibility complex (MHC) class II (MHCII) is constitutively expressed by immature dendritic cells (DC), but has a short half-life as a consequence of its transport to and degradation in lysosomes. For its transfer to lysosomes, MHCII is actively sorted to the intraluminal vesicles (ILV) of multivesicular bodies (MVB), a process driven by its ubiquitination. ILV have, besides their role as an intermediate compartment in lysosomal transfer, also been proposed to function as a site for MHCII antigen loading and temporal storage.

Trafficking of MHC class II in dendritic cells is dependent on but not regulated by degradation of its associated invariant chain.

In dendritic cells (DC), newly synthesized MHCII is directed to endosomes by its associated invariant chain (Ii). Here, Ii is degraded after which MHCII is loaded with peptides. In immature DC, ubiquitination of peptide-loaded MHCII drives its sorting to lysosomes for degradation.

MHC II in dendritic cells is targeted to lysosomes or T cell-induced exosomes via distinct multivesicular body pathways.

Dendritic cells (DCs) express major histocompatibility complex class II (MHC II) to present peptide antigens to T cells. In immature DCs, which bear low cell surface levels of MHC II, peptide-loaded MHC II is ubiquitinated. Ubiquitination drives the endocytosis and sorting of MHC II to the luminal vesicles of multivesicular bodies (MVBs) for lysosomal degradation.