current trends in mass spectrometry july 13 - 15, 2015 … · 50 µm 400 nm - 2 µm sample...
TRANSCRIPT
International Summit on
Current trends in Mass SpectrometryJuly 13 - 15, 2015New Orleans, Louisiana [email protected]
Outline
2
Introduction
Localized lipidomics
◦ Duchenne dystrophy
◦ NAFLD
◦ Cystic fibrosis
Special lipids
◦ Fabry disease
◦ Peptidolipids
◦ Cholesterol
Xenobiotics
◦ Environmental pollutant
◦ Preservative
◦ Anti-acne drug
3
After dissection, fast freezing at -80°C
Tissue is maintained with OCT glue
12-20 µm sections cut with a cryostat ( -20°C)
Tissue sections are deposited directly onto a stainlesssteel plate, a silicon wafer, or a glass plate
Dehydrated under vacuum
Fixed onto the standard sample holder
Blade
12 μm
section
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
4
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
5
D. Touboul et al.
J. Am. Soc. Mass Spectrom. 2005, 16, 1608-1618
Very good focus at unit mass
resolutionfield of view:
55 x 55 µm²
primary ion:
Bi3+
pixel size 215 nm
total ion
cholesterol
phosphocholine
superpositionoptical image:
field of view:
700 x 700 µm²
field of view:
55 x 55 µm²
primary ion:
Bi3+
total ion
cholesterol
phosphocholine
superimpositionoptical image:
field of view:
700 x 700 µm²
optical image:
field of view:
700 x 700 µm²
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
6
MALDI-TOF-TOF TOF-SIMS
Spatialresolution
50 µm 400 nm - 2 µm
SampleDehydrated,
Homogeneousmatrix coating
DehydratedNo fixationNo matrix
Mass range m/z > 200 m/z 1000
Compounds
Proteins,Peptides,Lipids,Drugs,
Metabolites,…
LipidsGlycosphingolipi
dsCyclopeptides,
Drugs,Metabolites, Elements,…
Analyzer TOF-MS/MS TOF-MS
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
DESI : Roger Webb (Monday morning)
MALDI : Mehran F Moghaddam (Monday Morning)
MeV SIMS : Roger Webb (Monday Afternoon)
Low Energy Cs+ SIMS : Purushottam Chakraborty
(Tuesday Morning)
7
MALDI-TOF-TOF TOF-SIMS
Spatialresolution
50 µm 400 nm - 2 µm
SampleDehydrated,
Homogeneousmatrix coating
DehydratedNo fixationNo matrix
Mass range m/z > 200 m/z 1000
Compounds
Proteins,Peptides,Lipids,Drugs,
Metabolites,…
LipidsGlycosphingolipi
dsCyclopeptides,
Drugs,Metabolites, Elements,…
Analyzer TOF-MS/MS TOF-MS
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
DESI : Roger Webb (Monday morning)
MALDI : Mehran F Moghaddam (Monday Morning)
MeV SIMS : Roger Webb (Monday Afternoon)
20 KeV Bi3+ TOF-SIMS
Low Energy Cs+ SIMS : Purushottam Chakraborty
(Tuesday Morning)
8
MALDI-TOF-TOF TOF-SIMS
Spatialresolution
10-50 µm 400 nm - 2 µm
SampleDehydrated,
Homogeneousmatrix coating
DehydratedNo fixationNo matrix
Mass range m/z > 200 m/z 1500
Compounds
Proteins,Peptides,Lipids,Drugs,
Metabolites,…
LipidsGlycosphingolipids
Cyclopeptides,Drugs,
Metabolites, Elements,…
Analyzer TOF-MS/MS TOF-MS
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
9
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
10
Fatty acids
O
OH
O
O
O
OP
O
O
O
O
HOHO
HOOH
OH
X
X = H, Na, K, Ca...
Glycerophospholipids:
Phosphatidylinositol
O
O
O
OP
O
O
O
ON Phosphatidylcholine O
HO
α-tocopherol (Vit E)
HO
Cholesterol
O
HN
OH
OP
O
OO
N
Sphingomyelin
O
O
O
O
O O
DiglyceridesO
O
O
O
OH
Triglycerides
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
11
500 µm
Microscope
optical image
573-79 = C34:(3-0)
mc:244 tc:409506599-607 = C36:(4-0)
mc:161 tc:283010
545-51 = C32:(3-0)
mc:185 tc:246767
519-23 = C30:(2-0)
mc:73 tc:78996
Diglycerides
668 = SM fragment
mc:6 tc:12085
616 = SM fragment
mc:7 tc:16129
(mode -)
642 = SM fragment
mc:7 tc:20513
(mode -)
687 = SM fragment
mc:9 tc:26892
(mode -)
385 = Cholesterol
mc:6 tc:14556
(mode -)
Sphingomyelins and cholesterol
Vitamin E (mode+)
mc:7 tc:12860
Vitamin E (mode -)
mc:14 tc:34882Vitamin E
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
12
N. Tahallah, A. Brunelle, S. De La Porte, O. Laprévote, J. Lipid Res. 2008, 49, 438-454
Adipocytes (infiltrates)
Damaged area
(necrotic tissue)
Muscular fibers
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
13
1000 µm
1000 µm
Control liver
Fatty liver
H&E staining (adjacent sections)
Accumulation of lipids (mainly diacyl- and triacylglycerols) inhepatocytes,
The predominant risk factor for NAFLD appears to be insulin-resistance related to the metabolic syndrome,
On stained sections, lipid vesicles are observed in fatty liver but arenot observable in healthy liver,
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
14
300 400 500 600 700 800 9000
1
2
3
4
5
6
Inte
nsity p
er
un
it a
rea
(co
un
ts x
10
3)
m/z
PC
DAG
Vit.E
Chol.
38
5.3
3
369.343
39.2
93
13.2
8
523.47603.44
577.43
551.43
430.36
758.55
760.56
MAG
300 400 500 600 700 800 9000
5
10
15
20
Inte
nsity p
er
un
it a
rea (
cou
nts
x10
3)
m/z
603.51
577.53
551.47
523.44
369.33
33
9.2
831
3.2
7
Chol.
DAG
700 750 800 850 900 9500.0
0.1
0.2
0.3
0.4
0.5
853.69
855.73
857.74
758.45
760.49
PC TAGMAG
Control liver Fatty liver - steatotic area
Strong decrease of vitamin E signal
Detection of triacylglycerols
Strong increase of diacylglycerols
D. Debois et al., Anal. Chem. 2009, 81, 2823-2831
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
15
Sum of DAG ions
19
0
50
0
79
0
64
0C30 DAGs C32 DAGs C34 DAGs C36 DAGs
16
0
179
0Cholesterol
100 µm
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
16
100 µmCholestérol
Red = DAG C30
Green = DAG C36Red = Unsaturated lipidsGreen = saturated lipids
300 400 500 600 7000
10
20
m/z
3
Inte
nsité p
ar
unité d
e s
urf
ace
(coups x
10
)
DAG C36
DAG C34
DAG C32
DAG C30
Ch
ole
sté
rol
MA
G M
AG
F. Le Naour et al.
Plos One, 4, issue 10, e7408 (1-10) (2009)
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
17
Usual way Whole mass spectrum (all pixels)
Extract ion images
ROIs Mass spectra
Definition of Regions of Interest (ROI)
from individual ion images
Co(anti)-localization of lipids
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
18
Usual way Whole mass spectrum (all pixels)
Extract ion images
ROIs Mass spectra
Definition of Regions of Interest (ROI)
from individual ion images
Co(anti)-localization of lipids
Manual process strongly dependant on
the operator subjectivity/experience
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
19
Aim: differentiate by TOF-SIMS imaging CF mouse models from
WT mices
Samples: colon crypts
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
WT CF
A B JI
C D LK
E F NM
G H PO
C16:1 FA
(Lieberkühn
glands)
C18:2 FA
(Border)
Cholesteryle
Sulfate
(Border)
C18:0 FA
(Lamina propria)
Vit E
PI or ST
fragment
(mucosa)
3-color
overlay
20
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
WT CF
A B JI
C D LK
E F NM
G H PO
C16:1 FA
(Lieberkühn
glands)
C18:2 FA
(Border)
Cholesteryle
Sulfate
(Border)
C18:0 FA
(Lamina propria)
Vit E
PI or ST
fragment
(mucosa)
3-color
overlay
21
Different distributions of lipids between the
histological substructures
No « clear » differences between CF and WT
samples
Strong inter-individual variations
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
22
Percent Variance Captured by PCA Model
Principal
Componen
t Number
Eigenvalu
e of
Cov(X)
%
Variance
Captured
by this PC
%
Variance
Captured
Total
1 0.37 37.45 37.45
2 0.18 17.97 55.42
3 0.12 11.65 67.06
4 0.07 7.29 74.35
5 0.06 5.50 79.85
6 0.05 4.58 84.43
7 0.04 3.80 88.23
8 0.04 3.72 91.95
9 0.03 3.38 95.33
10 0.02 1.90 97.23
11 0.01 1.06 98.30
12 0.01 0.65 98.95
13 0.00 0.49 99.45
14 0.00 0.40 99.85
15 0.00 0.15 100.00
STEP 2
multivariate PCA
selection of PCs’
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
23
Epithelial
border
STEP 3: representing pixels in the space of scores
PC1-PC2 plane
Lieberkühn Glands
Submucosa
Lamina propria
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
24
STEP 4: partitioning clustering of PCA 1-4 selected variables
2 clusters
4 clusters
3 clusters
5 clusters
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
25
STEP 4: partitioning clustering of PCA 1-4 selected variables
2 clusters
4 clusters
3 clusters
5 clusters
RESULTS
- Well-defined regions of interest (ROIs)
- Selection of ROIs for 7 WT and 6 CF samples
allows their comparison by PCA
- A Genetic Algorithm analysis of WT and CF
samples provides a list of the most
discriminating peaks
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
26
Ion mass (m/z) Ion Species Lipid family
109.99 [CH3O4P].- PE, PC, SM
164.92 fragment PI
168.08 [C4H11NO4P]- PC, SM
215.92 fragment CS, ST
220.91 fragment PI, ST
227.22 C14:0 carboxylate Fatty Acid
255.25 C16:0 carboxylate Fatty Acid
429.40 [Vitamine E – H]- VE
861.70 [TG52:0 – H]- TG
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
27
Lysosomal disease due to a lack of α-D-galactosidase-A (α-GALA) of
recessive transmission linked to the X chromosome
(affects 1 over 120 000 people)
Accumulation of Gb3 and Ga2 glycosphingolipids in fluids and tissues
O
OH OH
HOOH
O
O OH
HOOH
O O
HO
OH
OHO
HN
OH
O
Structure of a Gb3 (Trihexosylceramide) :
Osidic sequence
(a-Gal/b-Gal/b-Glu)
Acyl sequence
Ga2 (digalactosylceramide), Gal/Gal sequence
kidney deficiencies, neurological and cardiac evolutive lesions and
angiokeratomas
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
28
Lysosomal disease due to a lack of α-D-galactosidase-A (α-GALA) of
recessive transmission linked to the X chromosome
(affects 1 over 120 000 people)
Accumulation of Gb3 and Ga2 glycosphingolipids in fluids and tissues
O
OH OH
HOOH
O
O OH
HOOH
O O
HO
OH
OHO
HN
OH
O
Structure of a Gb3 (Trihexosylceramide) :
Osidic sequence
(a-Gal/b-Gal/b-Glu)
Acyl sequence
Ga2 (digalactosylceramide), Gal/Gal sequence
kidney deficiencies, neurological and cardiac evolutive lesions and
angiokeratomas
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
29
No treatment of the sample
500x500 µm2
256x256 pixels
Bi3+ primary ions
Acquisition time 30 min
Fluence 1012 ions.cm-2
+
950 1000 1050 1100 1150 1200
0
1000
2000
3000
4000
5000
Inte
nsity (
co
un
ts)
m/z
Detection of very intense Ga2 et Gb3 signals
Possible to localize a single species with a micrometerresolution
Colocalization with vitamin E, cholesterol and cholesterolsulfate
D. Touboul et al., Int. J. Mass Spectrom. 2007, 260, 158-165
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
30
HN
NH
HN
NH
HN
NH
HN
O
O
COOH
O
O
O
O
COOH
O
O
O
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
31
Image size: 500x500 µm²
Primary ions: Bi3+, 25 keV
Negative ion mode
PIDD: 5.1011 ions.cm-2
Pixel size: 2x2 µm2
Acquisition time: 30 min
12
34
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
32
12
3
4
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
33
12
3
4
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
Artwork
analysis• Dogon art
• Rembrandt
• Grünewald
34
Temporal cortex
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
35
Variation of cholesterol distribution along the cortex
(Alzheimer n=6, Controls n=4)
A. N. Lazar et al. Acta Neuropathologica, 125, 133-144 (2013)
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
36
Polybrominated flame retardants
Endocrine disruptive chemicals
Imaging of DBDE in organs of dosed rats vs. control
D
E
F
ControlDosed
G
H
I
2 mm
2 mm
Optical images
Cortex
Medulla
ADRENALS
A. SeyerJ. Am. Soc. Mass Spectrom. 21, 1836-1845 (2010),
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
37
Polybrominated flame retardants
Endocrine disruptive chemicals
Imaging of DBDE in organs of dosed rats vs. control
OVARIESControl
G
H
Dosed
D
E
2 mm
2 mm
Masson staining
A
B
-Accumulation in some of the numerous corpora lutea
-Dependant on the corpus luteum’s stage in the estrous cycle (?)
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
38
Used as preservative in eye drops of
prostaglandin derivatives and
betablockers as first line therapy for
glaucoma
But it is toxic:
→ Damage of tissues due to oxidative
stress
→Apoptosis
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
39
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
40
CORNEA
overlay
N. Desbenoit et al. Anal. Bioanal. Chem., 405, 4039–4049 (2013)
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
41
MALDI Imaging
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
42
TOF-SIMS Imaging
DrugDiglycerides
SphingomyelinHair follicle
→ colocalisation of the drug with the diglycerides around the
hair follicles
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
43
Portrait of Nicolaes van Bambeeck
Rembrandt van Rijn, 1641
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
Artwork
analysisRembrandt
44
1500 μm long
1st ground layer
Canvas
Red grain
2nd ground layer
Pictural layers
m/z 85
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
Artwork
analysisRembrandt
45
1500 μm long
m/z 85
(resin)
m/z 59
(saccharide
fragment:
starch)
Lipid ions
Amino
acids
Pb+
Pb2+
Pb3+
Lead
white
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
Artwork
analysisRembrandt
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
Artwork
analysisRembrandt
46
Lake pigment
Canvas
Starch
Lipid + lead
Resin
Lead white
Umber
STRATIGRAPHY OF THE SAMPLE
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
Artwork
analysisRembrandt
47
Introduction
Localized
lipidomics
• Duchenne
dystrophy
• NAFLD
• Cystic fibrosis
Special lipids• Fabry disease
• Peptidolipids
• Cholesterol
Xenobiotics• Environmental
pollutant
• Preservative
• Anti-acne drug
Artwork
analysis• Rembrandt
• Grunewald
48
For tissue imaging, the micrometer lateral resolution is enough in many cases (SIMS)
The mass resolution and mass accuracy should be as high as possible
Many organic ions can be identified by their co-localization with specific fragments (SIMS) or by MS/MS (MALDI). Don’t forget the gas phase dissociation chemistry !
Identification by spectral comparisons with standard compounds is always useful
The targeted compounds must be highly concentrated in well-defined areas to be imaged.
In biology, the expertise of histologists and/or collaboration with clinicians is mandatory.
In SIMS In situ identification by MS/MS is lacking complementarity with MALDI-MSMS.
49
Grants:
Agence Nationale de la Recherche
Scientifique (ANR)
European Union (FP6 STREP Program)
Institut de Chimie des Substances Naturelles
(ICSN)
Centre National de la Recherche Scientifique
(CNRS)