Endoplasmic Reticulum (ER)

		FUNCTION
Rough ER	ribosomes attached to its outer (cytoplasmic) surface.	Rough ER lies immediately adjacent to the cell nucleus, and its membrane is continuous with the outer membrane of the nuclear envelope. The ribosomes on rough ER specialize in the synthesis of proteins that possess a signal sequence that directs them specifically to the ER for processing.
Smooth ER	not associated with ribosome	The smooth ER is involved in the synthesis of lipids, including cholesterol and phospholipids, which are used in the production of new cellular membrane.

Exosome

• Exosomes are small extracellular vesicles with a diameter of 30 to 150 nm derived from the membranes of various cell types, including microglia and neurons (He et al., 2018).
• [MJF PDRx 20240501]
  • 5% of plasma aSyn is in the EV fractions
  • Phosp aSyn is enriched in EVs (plasma)
  • aSyn in CSF EVs was below LoD for half of the control samples

function

• the transmission of biomacromolecules.
• Since exosomes are membrane-permeable and have low immunogenicity, these nanoparticles have been extensively used as biological carriers to deliver multiple therapeutic compounds that could avoid phagocytosis and bypass lysosomal engulfment

Limitation of exosome

• Lack of validation of the cellular orginin of the exosomes.
  • contamination 도 rule out 해야 함
  • peripheral origin 도 rule out 해야 함.
  • 다른 tissue 도 rule out 해야 함.
• Pituitary
  • Pituitary gland is outside of the BBB!
• Skeletal m
  • Gene
    • skm

Process

• Exosome Diagnostics, Inc (exosomedx) :
  • Exosome Dx Depletion Enrichment (EDDE)
    • The patented EDDE platform can select exosomes derived from a specific tissue type,
      • Depletion: of non-relevant exosomes &
      • → Enrichment: of specific target you want (어떤 방법으로 Depletion & Enrichment 하는지는 비밀이겠다)
      • → RNASeq → mapping → analysis
        • biotype distribution
        • correlation
• ERCC
  • mRNA Transcriptome analysis, differential expression
  • Consortium
    • ERCC (Extracellular RNA Communication Consortium)

Example

IP6 {Anderson, 2021 #1266}

ExoQuick

Otake: IP6 was detected by CSF concentration by ExoQuick (not detected by other EV isolation methods - ExoEasy, ExoIntact).

4 NDE

neuronal exosome enrichment procedure

L1CAM (L1 cell adhesion molecule)	in the CNS the expression of cell adhesion molecule L1CAM is primarily restricted to neurons, the presence of this protein in the exosomes demonstrates its neuronal origin, 비고: both soluble and membrane-bound L1CAM are present, and because L1CAM is expressed also outside the brain in non-neuronal cells and in other tissues. (Dutta, 2021 #1542) Its presence cannot distinguish between peripheral and central neurons {Anderson, 2021 #1560).
GluR2
neurofilament medium (NEFM)

NDE in PD

0220201 Zicha

MSD) α-syn assay used in TAK-341 clinical development detects quantifiable free levels in neuronal exosomes enriched with L1-CAM and GluR2 N=10 HC and PD matched sets of plasma and CSF Looked at mRNA and α-syn changes between HC and PD in enriched neuronal exosomes Neat CSF and plasma has no difference in syn levels . L1CAM and GluR2 enriched neuronal exosomes have significantly higher levels of syn without any overlap with HC samples

Oligodendrocyte-derived exosome

	sample		MARKER
	Living person	Postmortem
PD & MSA (N=32)	Serum collection Peripheral blood from living persons was drawn by venipuncture using a BD Vacutainer push-button blood-collection kit and left to coagulate in silicone-coated serum-collection tubes for 15-20 min. → After centrifugation at 1500g for 15 min at 4 °C, → the serum was collected and either processed immediately or aliquoted and stored at − 80 °C Plasma collection Plasma samples were obtained as described previously [2]. Briefly, peripheral blood was drawn by venipuncture and collected into EDTA tubes. → Within 30 min of collection, the plasma tubes underwent centrifugation at 4 °C for 15 min at 1500g. → The plasma then was aliquoted into 0.5 mL aliquots (control samples) or 1.0 mL aliquots (MSA samples) and stored at − 80 °C.	After discovering that samples stored for > 5 years had reduced signal (Supplementary Information), all of these samples were replaced with new samples stored < 5 years. Postmortem serum was obtained as described previously [5]. Briefly, blood was drawn from the left ventricle by a transthoracic puncture using 30-mL, disposable, polyethylene syringes fitted with 8-cm long, 18-gauge needles. → Serum was separated from the blood using standard separator vacuum tubes (7 mL) prior to 10 min centrifugation, → aliquoted into 0.5-mL polyethylene microcentrifuge tubes, and	MSA: 2,3-cyclic nucleotide-3-phosphodiesterase (CNPase). CNPase is present on the cytosolic side of non-compact myelin [14, 66] and the intermembrane space of mitochondria [37], which may limit its presentation on the surface of exosomes MOG (myelin-oligodendrocyte glycoprotein): MOG, because it is a membrane-bound protein [7] and because specific commercial antibodies are available against its extracellular domain, which might be exposed on the surface of exosomes	α-Syn concentrations were lower in the exosomes from patients with MSA than in those with PD, yet the differences were small and the degree of overlap between the groups was high α-Syn concentrations were particularly high in the MSA group compared to the control and PD groups. The ratio between α-syn concentrations in putative oligodendroglial versus neuronal exosomes was found to be a sensitive biomarker for distinguishing between PD and MSA.

general good review: 2012 London, Sung

Uncertain Spans

location	transcription	uncertainty
Oligodendrocyte / Living-person serum / EDDE-related literature reference	inline reference [2] and [5] are kept as written; the precise bibliography is not visible on this page.	citation continuity.
Oligodendrocyte / MARKER cell / [14, 66] / [37] / [7]	inline numeric citation markers are preserved verbatim.	citations not expanded.
Oligodendrocyte-derived exosome figure / y-axis label	the y-axis label log[α-synuclein] (pg/mL) is partially clipped in the source crop.	low-quality glyphs, transcribed from the visible portion.