Undergrad Presentations

new cases of brain cancer yearly

320,000

10% of brain cancer deaths are

under 20 worldwide

malignant brain tumors median life expectancy

2-3 years

brain cancer economic burden

$1 trillion annually

gangliosides

glycosphingolipids with one or more sialic acid residues

ceramide backbone linked to

sialic acid-containing oligosaccharides

nomenclature

indicates number/type of sialic acids

gangliosides are classified into

a and b series

gangliosides regulated by

glycosyltransferases

gangliosides localized to

outer leaflet of plasma membrane

gangliosides form

part of lipid rafts

gangliosides

play essential roles in neural development and provide extracellular targets accessible by antibodies

gangliosides role in tumor progression

Promote cell proliferation, adhesion, migration, and invasion via integrin-FAK and downstream MAPK signaling

gangliosides engage in

cell-matrix interactions

neuroblastoma

igh b-pathway ganglioside content

ganglioside immune suppression

T-cell apoptosis

gd2 multi modal therapeutic stategies

Antibody Therapy: Dinutuximab, naxitamab, radioimmunotherapy, bispecific antibodies, car-t cell therapy, nanoparticle drug delovery, vaccines and immunomodulation

gd2 structure

glucosylceramid backbone + two sialic acids (disialo) + lactose group + exposed galnac + gd3

gd3 vs gd2

abundant in early-development, gd2 more specialized, tumor associated marker

gd2 focus

clustering and organizing signaling complexes

gd2 expression higher in developing brain

as a fraction of gangliosides, expressed on neural progenitors and immature glia.

gd2 expression in adult brain

downregulated, but present in hypothalamus and hippocampus

high gd2/gd3 in fetal brain

make membranes very responsive to growth and migration signals; as the brain matures and wants stability, it shuts that system down, so GD2 expression drops

st8sia1 and b4galnt1 genes upregulated

driven by oncogenic TFs and de-repression of loss of PRC2 and EZH2

pro-tumor GD2 signaling

growth factor clustering, tenascin-C ECM interactions to promote migration, and creates deep tissue stem cell milieu

gliomas shed gd2

contribute to immunosuppressive glyco-cloud

O-Ac-GD2

GD2 biomarker

gd3 is a crucial marker

on neural stem cells and is not selective for tumor cells and is necessary for normal neurogenesis

oacGD2 not expressed on same fibers as

GD3

gd2 targetting issues

not a homogeneously expressed target, can affect other nerves, does not have an internal tail for receptor target, shieled by hyaluronan rich ECM

GD2-specific CAR T cell

potent and specific anti-tumor activity in vitro

intracerebral vs intravenous

intracerebral more effective

gd2 car t cell activation

powerful and specific release of effector molecules

gd2 car t cell therapy advantages

safe, anti-tumor (half the patients achieving partial response), expanded in patients, surviving tumor stopped expressing GD2

nanoparticles composition

carbon, metal, ceramic, lipid based

siRNAs

anti-gd-2 conjugaged liposome

silica based NP

delivered miR-34a

iron oxide NPs

selective binding and internatlization at 14%

3F8 targeted nanoparticles

dramatically improve survival and tumor response

expansion of gd2 usage

metastatic melanoma, sarcomas, solid tumors

concurrent treatment with

braf and mek kinase inhibitors

gd2 therapy limitation

can increase pro-tumorigenic myeloid cell activity

Which of the following was not a conclusion reached in the study of GD CAR-T cells against human glioblastoma (Prapa et al., 2021)?

The intravenous delivery route is significantly more effective than the intercerebral route.

other car t cell limitations for GD2

antigen loss, immunosuppressive tumor microenvironment

NP drug delivery limitations

inability to evade immune surveillance, poor cell-specific targeting, inadequate biocomptability

mesenchymal stem cells properties

tumor homing, target cell, immunomodulatory

MSCs production

modify and isolate cell membranes, coat nanoparticles with the isolated membranes

colon cancer msc therapy

dox-loaded iron oxide NP with MSC coating

MSC coated NP

reached colon tumors more efficiently and killed more tumors

bone cancer NP

DOX and PD-L1 siRNA with MSC coating

MSC coating

improved chemoimmunotherapy for metastatic prostate cancer

MSC NPs also worked for

breast cancer therapy

MSC NPs disadvantage

safety, immaturity, receptor complications

What is NOT an advantage of MSC membrane-coated nanoparticles compared to traditional nanoparticles?

They have more mature manufacturing processes and techniques

BBB

The layer of cells that separates the brain from the blood supply

BBB selective permeability

tight junctions connecting ECs, low EC transcytosis rates, ABC transporters

autoimmune disorders

multiple sclerosis, neuromyelitis optica spectrum disorder, neuropsychiatric systemic lupus erythematosus, myelin oligodendrocyte glycoproteiin antibody-associated disease, autoimmune encephalitis

MS pathogenesis

damage to BBB allows for infiltration of autoreactive immune cells, CD4 t cells interact with APCs → inflammatory damage

BBB delivery

device assisted, fluid based, biobased

intranasal delivery with bmsc exosomes

microglia regulation + noninvasive approached

intranasal effects

decrease demyelination and upregulated TJ protein levels

btk inhibitor tolebrutinib

inhibits bruton’s tyrosine kinase

Tolebrutinib regulated

neuroinflammation

In the development of a BTK inhibitor such as tolebrutinib for MS treatment, crossing the BBB is critical for effect on microglia and B-cell activation within the CNS. Which of the following statements about the effectiveness of tolebrutinib's BBB permeability and the implications this has for future MS therapies is not true?

Phase 3 Clinical trials demonstrate tolebrutinib significantly reduces brain lesions in MS with IC50 CSF concentration levels

aAPCs

egineered immune cells displaying antigens on their surface

acellular aAPCs

easier to produce, manipulate, but more difficult to achieve biomimetic immune-cell interactions

cellular aAPCs

modulable, yet biomimetic; ease of expansion, higher risk of rejection

T cell activation

peptide MHC or anti-CD3 → presentation and reception of stim ligands → local and tethered cytokines

cancer immunotherapies challenge

immunosuppressive, poor tumor infiltration, toxicity, reprograming risk, immunogenicity

aAPCs push the

immune system to attack cancer cells with much more specificity than conventional methods.

cell specific activation

express both antigen presenting complexes and costim surface ligands

k562 chose because

modulated to not express HLA, compatible with lentiviral infection

Specified activation in co-culture conditions allows

expansion of antigen- specific sub-classes of immune cells with modulation of MHC/HLA expression and costimulatory modecule expression

lipid based delivery

importance of the lipid bilayer in the APC

lipid method improvements

need controlled cholersterol concentration, lipid composition, and in vivo experiments

large aAPCs had

greater T-cell activation compared to small aAPCs

large tubes vs large scpheres

large tubes more effective

what’s not explicitly required for artificial apcs to activate t cells

cytokine stimulation of t cells

neurodegenerative disorders

progressive loss of neurons

bbb permeability

only 90% small molecule drugs and nearly 100% larger drugs can’t overcome it

lpr1 targeted NPs

treat alzheimer’s disease

alzheimer’s NP

reduced AB by almost half, resyored LPR1, upregulated PACSIN2, cleared AB deposits; unknown safety risks

plga-g7 cholesterol loaded NPs

huntington’s disease

plga-g7 results

increased expression of synaptic proteins, did not reverse brain atrophy, low drug loading

selenium/human serum albumin NPs

crossed intensitnal and BBB for parkinson’s; improved motor function and safety

future clinical applications

overcome BBB, neuroprotection, more long term safety and dosing studies

Which is not an advantage of cholesterol-loaded NPs to treat Huntington’s disease?

restore motor function

mrna-lnps function

deliver nucleic acids to cells, allow for accumulation of nucelic acids in cytoplasm, protect from degradation

ionizable lipid

endosomal escape

phospholipid

bilayer structure

cholesterol

adds membrane stability

peg-lipid

reduces immune clearance and prevents aggregation

passive targeting

no modficiations, high-throughput, enhanced permeability, direct injection, promote cd4+ and cd8+ t cell activation

active targeting

direct modification of mrna-lnps

113-012B targets

lymph node

113-o12b effects

increased cd8+ t cell activity, slowed tumor growth, and improved survival

synthesize large library of bbb crossing lipid

combine with ionizable amino lipids = BLNPs

BLNPs results

higher BBB penetration, higher transfection efficiency, target both neurons and astrocytes

BBB crossing mechanism for BLNPs

caveolae mediate transcytosis, y secretase associated transport pathways

MK16 BLNPs safety

no major toxicity