1. Immunology and Inflammation
  2. Microbiology and Infectious Disease
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Plasmodium-specific atypical memory B cells are short-lived activated B cells

  1. Damián Pérez-Mazliah
  2. Peter J Gardner
  3. Edina Schweighoffer
  4. Sarah McLaughlin
  5. Caroline Hosking
  6. Irene Tumwine
  7. Randall S Davis
  8. Alexandre J Potocnik
  9. Victor LJ Tybulewicz
  10. Jean Langhorne  Is a corresponding author
  1. The Francis Crick Institute, United Kingdom
  2. MRC National Institute for Medical Research, United Kingdom
  3. University of Alabama at Birmingham, United States
  4. The University of Edinburgh, United Kingdom
Research Article
Cite this article as: eLife 2018;7:e39800 doi: 10.7554/eLife.39800
9 figures, 1 table and 3 additional files

Figures

Figure 1 with 2 supplements
Analysis of total bone marrow and splenic B-cell populations in IghNIMP23/+ and Igh+/+littermates.

(A) Flow cytometry gating strategy to identify different B-cell populations in bone marrow of IghNIMP23/+ mice. Arrows indicate flow of analysis. The same strategy was used for Igh+/+ littermates. (B) Percentages and numbers of different B-cell populations in bone marrow of IghNIMP23/+ and Igh+/+ littermates as defined in (A). (C) Flow cytometry gating strategy to identify different B-cell populations in spleen of IghNIMP23/+ mice. (D) Percentages and numbers of different B-cell populations in spleen of IghNIMP23/+ and Igh+/+ littermates as defined in (C). Data are representative of two independent experiments with four mice per group. (E) Flow cytometry analysis of B cells obtained from spleen of Igh+/+ (left) and IghNIMP23/+ (right) mice stained with anti-B220 and CD19 antibodies in combination with an MSP121 fluorescent probe. The gates show the frequency of B cells specific to MSP121. (F) Frequencies of MSP121-specific splenic B cells in IghNIMP23/+ and wild-type Igh+/+ littermate controls (Mann Whitney U test). Data pooled from two independent experiments with 3–5 mice per group. Mann Whitney U test. *p<0.05. Error bars are SEM.

https://doi.org/10.7554/eLife.39800.002
Figure 1—figure supplement 1
Generation of IghNIMP23/+knock in mice.

Annotated DNA and corresponding amino acid sequence of VDJHNIMP23 obtained from (A) gDNA including the Leader-V intron and (B) cDNA, of the NIMP23 hybridoma: start Methionine (Met) indicated by red star, intron splice donor and acceptor sites highlighted in red, dots indicate STOP codons, black bars indicate predicted complementarity determining regions according to the Kabat database (Johnson and Wu, 2001) (C) IMGT/V-Quest mouse Ig database (Lefranc et al., 1999) comparative analysis result summary of the gDNA derived VDJHNIMP23 sequence reveals the identity of the closest matching endogenous V and J genes (D) Schematic representation of (Igh+) Endogenous IgH locus showing the 4 JH segments, the DQ52 element, the Igh intronic enhancer (EH), the switch region for the constant µ gene (S), and (below) targeting construct indicating 5’ and 3’ homology arms and the inverted loxP-neor-loxP cassette and rearranged VDJHNIMP23 variable heavy chain region gene of the NIMP23 hybridoma, replacing DQ52 and all four JH segments of the endogenous IgH gene. IghNIMP23neo: Targeted Igh locus after homologous recombination. IghNIMP23: Final allele after Cre-mediated removal of neor.

https://doi.org/10.7554/eLife.39800.003
Figure 1—figure supplement 2
Generation of mixed bone marrow chimera model with reduced precursor frequency of IghNIMP23/+ B cells to study MSP121-specific B cell responses during P. chabaudi infection.

(A) Experimental strategy to generate mixed bone marrow chimeric mice. (B) Numbers of different splenic B-cell populations defined by flow cytometry in Rag2-/-.C57BL/6.SJL-Ptprca mice reconstituted with a mixture of IghNIMP23/+ and C57BL/6.SJL-Ptprca bone marrow in a 10:90 ratio (NIMP23→ Rag2-/-), and control mice reconstituted with C57BL/6.SJL-Ptprca bone marrow (WT→ Rag2-/-). Mann Whitney U test. Error bars are SEM. Data are representative of two independent experiments with five mice per group. (C) Flow cytometry of B cells obtained from different tissues of NIMP23→Rag2-/- chimeric mice. Gates show frequencies of CD45.1+CD45.2- and CD45.1-CD45.2+ (D) Flow cytometry of B cells obtained from spleen of NIMP23→Rag2-/- and WT→Rag2-/- control chimeric mice. Gates show frequencies of MSP121-specific B cells as determined by CD45.2 vs MSP121 staining. (E) Frequencies of CD45.1-CD45.2+ (black) and CD45.2+MSP121+ (grey) B cells as gated in C and D, obtained from different organs of NIMP23→Rag2-/- chimeric mice. (F) Blood-stage P. chabaudi parasitemia following mosquito transmission in NIMP23→Rag2-/- and WT→Rag2-/- control chimeric mice. (G) Flow cytometry data showing frequencies of MSP121-specific GC (CD38loGL-7hi) and class-switched (IgDIgG2bhi) B cells in the spleen of NIMP23→Rag2-/- chimeric mice before infection (day 0) and at day 35 post-mosquito transmitted P. chabaudi infection. (H) Numbers of MSP121-specific B cells, GC and class-switched B cells in the spleen of NIMP23→Rag2-/- chimeric mice as gated in B and E. Mann Whitney U test. Error bars are SEM. Data representative of two independent experiments with 3–7 mice per group.

https://doi.org/10.7554/eLife.39800.004
Generation of MSP121-specific AMB in response to mosquito transmitted P.chabaudi infection.

(A) Flow cytometry showing differential expression of CD11b and CD11c on splenic MSP121-specific B cells from NIMP23→Rag2-/- chimeric mice before infection (day 0) and at 35 and 155dpi. (B) Numbers of splenic MSP121-specific CD11b+CD11c+ AMB from NIMP23→Rag2-/- during the course of mosquito transmitted P. chabaudi infection. Kruskal-Wallis test vs day 0. ****, p<0.0001 (C) Flow cytometry showing expression of CD21/35, FCRL5, IgD, CD273 and CD80 on different subsets of splenic MSP121-specific B cells from NIMP23→Rag2-/- chimeric mice defined based on CD11b and CD11c expression at 35dpi. (D) Geometric mean fluorescence intensity (MFI) of CD21/35, FCRL5, IgD, CD273 and CD80 expression on different subsets of splenic MSP121-specific B cells from NIMP23→Rag2-/- chimeric mice defined based on CD11b and CD11c expression at 35dpi. (E) Frequencies of CD21/35, FCRL5, IgD, CD273 and CD80 positive cells among different subsets of splenic MSP121-specific B cells from NIMP23→Rag2-/- chimeric mice defined based on CD11b and CD11c expression at 35dpi. Two-way ANOVA vs CD11b-CD11c- subset. *p<0.05; **p<0.01, ***p<0.001; ****p<0.0001. Error bars are SEM. Data pooled from three independent experiments with 3–5 mice per group.

https://doi.org/10.7554/eLife.39800.005
Figure 3 with 2 supplements
Transcriptome analysis of sorted splenic MSP121-specific CD11b+CD11c+AMB.

MSP121-specific CD11b+CD11c+ (AMB) and CD11bCD11c B cells were flow cytometry sorted from the spleen of NIMP23→Rag2-/- chimeric mice at 35dpi; MSP121-specific B cells were flow cytometry sorted from the spleen of naïve NIMP23→Rag2-/-, and these three B cell populations were submitted to mRNAseq analysis. The heat maps display level of expression of selected individual genes, organized in functional clusters related to (A) Fc receptor like molecules, (B) cell trafficking, (C) cytokines, (D) transcription factors, (E) inhibitory receptors, (F) antigen experience/memory, (G) immunoglobulins, (H) galectins, (I) apoptosis, (J) proliferation, (K) plasma cells/plasmablasts/germinal centers, (L) surface markers. Each column corresponds to data from an individual mouse (n = 5 35 dpi, n = 5 0 dpi).

https://doi.org/10.7554/eLife.39800.006
Figure 3—figure supplement 1
Gating strategy for the sorting of splenic MSP121-specific CD11b+CD11c+ AMB and CD11bCD11c B cells at 35dpi.
https://doi.org/10.7554/eLife.39800.007
Figure 3—figure supplement 2
Profile of the Running ES Score and positions of GeneSet members on the rank ordered list for selected Reactome pathway gene sets.
https://doi.org/10.7554/eLife.39800.008
Generation of splenic MSP121-specific CD11b+CD11c+AMB in response to immunization.

(A) Flow cytometry showing differential expression of CD11b and CD11c on splenic MSP121-specific B cells from IghNIMP23/+ mice before immunization (day 0) and at days 1 and 3 post-immunization with R848 and MSP121. (B) Flow cytometry showing expression of FCRL5 and CD80 on different subsets of splenic MSP121-specific B cells from IghNIMP23/+ defined based on CD11b and CD11c expression at day one post-immunization and naïve mice. (C) Geometric MFI of FCRL5 and CD80 expression on different subsets of splenic MSP121-specific B cells from IghNIMP23/+ defined based on CD11b and CD11c expression at day one post-immunization. Two-way ANOVA vs CD11bCD11c subset. ****p<0.0001. (D) Flow cytometry of CD38 vs GL-7 (GC markers) on CD11b+CD11c+ MSP121-specific B cells from IghNIMP23/+ at day one post-immunization. (E) Numbers of splenic CD11b+CD11c+ MSP121-specific B cells from IghNIMP23/+ during the course of immunization. Kruskal-Wallis test compared to day 0. **p<0.01. Error bars are SEM. Data pooled from three independent experiments with 3–5 mice per group.

https://doi.org/10.7554/eLife.39800.009
Detection of MSP121-specific Bmem after resolution of P.chabaudi infection.

(A), (B) and (C) Flow cytometry showing gating strategy to identify splenic IgM/Dhi and IgM/Dlo CD273+ and/or CD80+ MSP121-specific Bmem in NIMP23→Rag2-/- chimeric mice before infection (day 0), at 35 and 155dpi, respectively. (D) Numbers of splenic IgM/Dhi and IgM/Dlo CD273+ and/or CD80+ MSP121-specific Bmem in NIMP23→Rag2-/- chimeric mice during the course of mosquito transmitted P. chabaudi infection. Two-way ANOVA vs day 0. **p<0.01; ***p<0.001; ****p<0.0001. (E) Flow cytometry showing expression of CD38 on different subsets of splenic IgM/Dhi and IgM/Dlo MSP121-specific B cells from NIMP23→Rag2-/- chimeric mice defined based on CD273 and CD80 expression at 155dpi. (F) Geometric MFI of CD38 expression on different subsets of IgM/Dhi and IgM/Dlo splenic MSP121-specific B cells from NIMP23→Rag2-/- chimeric mice defined based on CD273 and CD80 expression at day 155 post-mosquito transmitted P. chabaudi infection. Two-way ANOVA vs CD273-CD80- subset. **p<0.01; ***p<0.001; ****p<0.0001. Error bars are SEM. (G) Flow cytometry of CD273 and CD80 expression on non-GC (CD38hiGL-7lo, blue) and GC (CD38loGL-7hi, red) splenic MSP121-specific B cells from NIMP23→Rag2-/- chimeric mice at 35dpi. (H) Flow cytometry of CD38 vs GL-7 (GC markers) on splenic MSP121-specific B cells from NIMP23→Rag2-/- chimeric mice at 0 and 155dpi. (I) CD11b+CD11c+ MSP121-specific B cells overlaid on the CD80 vs CD273 plot corresponding to total MSP121-specific B cells. Data pooled from three independent experiments with 3–7 mice per group.

https://doi.org/10.7554/eLife.39800.010
Figure 6 with 2 supplements
FCRL5hi identifies MSP121-specific Bmem after resolution of P.chabaudi infection.

(A) Flow cytometry showing expression of FCRL5 (right) on different subsets of splenic MSP121-specific B cells from NIMP23→Rag2-/- chimeric mice defined based on CD273 and CD80 expression (left) at 155dpi. (B) t-SNE analysis of splenic MSP121-specific B cells based on FCRL5, CD38, IgD, CD273 and CD80 expression measured by flow cytometry (n = 5). Clusters identified by PhenoGraph are colored and numbered. (C) PhenoGraph heat map showing median expression of FCRL5, CD38, IgD, CD273 and CD80 on the different clusters of MSP121-specific B cells. Arrows point at the different clusters displaying a memory B cell phenotype. (D) Expression profiles of FCRL5, CD38, CD273 and CD80 for the different PhenoGraph clusters visualized on the first component of ISOMAP. The regression line estimated using the generalized linear model (GLM) is added for each marker. Data representative of three independent experiments with 4–7 mice per group. (E) Heat map showing expression levels of different genes on splenic FCRL5 and FCRL5hi MSP121-specific B cells sorted at 155dpi, and MSP121-specific B cells sorted before infection (naïve), determined by RNAseq analysis. Each column corresponds to data from an individual mouse (n = 5 155 dpi, n = 5 0 dpi).

https://doi.org/10.7554/eLife.39800.011
Figure 6—figure supplement 1
Gating strategy for the sorting of splenic MSP121-specific FCRL5hi Bmem and FCRL5 B cells at 155dpi.
https://doi.org/10.7554/eLife.39800.012
Figure 6—figure supplement 2
High expression of FCRL5 identifies Bmem.

(A) Flow cytometry gating strategy to identify splenic MSP121-specific FCRL5neg (red) and FCRL5hi (blue) B cells, and additional surface markers expressed on these cells, in NIMP23→ Rag2-/- mixed bone marrow chimeras infected with P. chabaudi (155dpi, top row) and immunized with recombinant MSP121 in Titermax Gold emulsion (day 29 post-immunization, bottom row). (B) Cumulative data showing geometric MFI for CD80, CD273, CD73, and CD38 memory markers on splenic MSP121-specific FCRL5neg and FCRL5hi B cells obtained from immunized mice. Mann Whitney U test. **, p<0.01. Error bars are SEM. Data representative of two independent experiments with 3–5 mice per group.

https://doi.org/10.7554/eLife.39800.013
MSP121-specific AMB are a distinct short-lived activated B cell subset.

(A) Principal component analysis of RNAseq transcriptome data from splenic MSP121-specific AMB (CD11b+CD11c+, 35dpi), CD11bCD11c B cells (35dpi), Bmem (FCRL5hi, 155dpi), FCRL5 B cells (155dpi) and B cells from naïve mice (0dpi). The MSP121-specific AMB and Bmem are contained inside ellipses. (B) (C) (D) (E) Normalized counts corresponding to selected genes representing memory B-cell markers, anti and pro-apoptotic genes, immunoglobulins and atypical memory B-cell markers, respectively, for all five groups described in (A). Each bar represents an individual mouse. Data generated with five mice per group.

https://doi.org/10.7554/eLife.39800.014
Analysis of MZ, B1 and GC B cell characteristics on MSP121-specific AMB.

(A) MSP121-specific CD11b+CD11c+ (AMB) and CD11bCD11c B cells were flow cytometry sorted from the spleen of NIMP23→Rag2-/- chimeric mice at 35dpi; MSP121-specific B cells were flow cytometry sorted from the spleen of naïve NIMP23→Rag2-/-, and these three B cell populations were submitted to mRNAseq analysis. The heat map displays level of expression of selected individual genes known to be up or downregulated on either MZ, B1 B cells or both. Each column represents an individual mouse. (B) Flow cytometry analysis of surface markers of either MZ, B1 B cells or both, on MSP121-specific CD11b+CD11c+ (AMB) (blue) and MSP121-specific IgMhi (red) B cells from the spleen of IghNIMP23/+ mice at 20dpi. (C) Flow cytometry analysis of GC markers on MSP121-specific CD11bCD11c (non-AMB, left) and CD11b+CD11c+ (AMB, right) B cells from the spleen of IghNIMP23/+ mice at 20dpi. (D) Flow cytometry analysis showing the expression of CD11b and CD11c on MSP121-specific CD11b+CD11c+ (AMB, blue) compared to GC (CD38loGL-7hi, red) B cells from the spleen of IghNIMP23/+ mice. Data generated with 5–6 mice per group.

https://doi.org/10.7554/eLife.39800.015
Author response image 1

Tables

Key resources table
Reagent
type (species)
or resource
DesignationSource or
reference
IdentifiersAdditional
information
Genetic
reagent
(M. musculus)
B6.SJL-Ptprca Pepcb/BoyJ
(B6.CD45.1)
The Jackson
Laboratory
MGI:4819849Bred in the specific
pathogen-free
facilities of the MRC
National Institute
for Medical Research
and The Francis Crick
Institute
Genetic reagent
(M. musculus)
Rag2tm1Fwa(Rag2-/-)The Jackson
Laboratory
MGI:1858556Bred in the
specific pathogen-
free facilities of the
MRC National Institute
for Medical Research
and The Francis Crick
Institute
Genetic reagent
(M. musculus)
IghNIMP23/+This paper_Bred in the specific
pathogen-free facilities
of the MRC National
Institute for Medical
Research and The Francis
Crick Institute
Strain,
strain background (Plasmodium
chabaudi
chabaudi,

strain AS)
P. chabaudiother_European Malaria
Reagent Repository,
University of Edinburgh.
Strain,
strain
background
(Anopheles
stephensi,
strain
SD500,
female)
mosquitosPMID: 23217144_Bred in Jean
Langhorne's lab
AntibodyMonoclonal
Rat Anti-CD11b
BD Biosciences563553(dil 1/50)
AntibodyMonoclonal
Hamster
Anti-Mouse
CD11c
BD Biosciences561022(dil 1/50)
AntibodyMonoclonal
Rat Anti-Mouse
CD138
BD Biosciences553714(dil 1/400)
AntibodyMonoclonal
Rat Anti-Mouse
CD19
BD Biosciences565076(dil 1/200)
AntibodyMonoclonal
Rat anti-Mouse
CD19
Biolegend115530(dil 1/400)
AntibodyMonoclonal
Rat anti-Mouse
CD19
Biolegend115543(dil 1/400)
AntibodyMonoclonal
Rat anti-Mouse
CD1d
Biolegend123510(dil 1/100)
AntibodyMonoclonal
Rat anti-mouse
CD2
Biolegend100112(dil 1/100)
AntibodyMonoclona
Rat
Anti-Mouse
CD21/35
BD Biosciences563176(dil 1/100)
AntibodyMonoclona Rat
Anti-Mouse
CD21/35
BD Biosciences553818(dil 1/100)
AntibodyMonoclonal Rat
anti-Mouse
CD23
eBioscience25–0232(dil 1/100)
AntibodyMonoclonal Rat
anti-Mouse
CD273
BD Biosciences564245(dil 1/25)
AntibodyArmenian
Hamster
anti-Mouse
CD3
Biolegend100336(dil 1/100)
AntibodyMonoclonal Rat
anti-Mouse
CD38
Biolegend102718(dil 1/400)
AntibodyMonoclonal Rat
anti-Mouse
CD38
eBioscience17–0381(dil 1/400)
AntibodyMonoclonal Rat
anti-Mouse
CD38
BD Biosciences740697(dil 1/400)
AntibodyMonoclonal
Rat anti-Mouse
CD4
Biolegend100414(dil 1/400)
AntibodyMonoclonal Rat
anti-Mouse
CD45.1
Biolegend110706(dil 1/400)
AntibodyMonoclonal Rat
anti-Mouse
CD45.1
Biolegend110728(dil 1/400)
AntibodyMonoclonal Mouse
anti-Mouse
CD45.2
BD Biosciences563685(dil 1/50)
AntibodyMonoclonal Mouse
anti-Mouse
CD45.2
Biolegend109814(dil 1/50)
AntibodyMonoclonal
Mouse
anti-Mouse
CD45.2
Biolegend109808(dil 1/50)
AntibodyMonoclonal
Rat
anti-Mouse CD45R/B220
BD Biosciences564449(dil 1/400)
AntibodyMonoclonal
Rat
anti-Mouse CD45R/B220
Biolegend103224(dil 1/400)
AntibodyMonoclonal
Rat
anti-Mouse CD45R/B220
eBioscience25–0452(dil 1/400)
AntibodyMonoclonal
Rat anti-Mouse
CD73
BD Biosciences550741(dil 1/100)
AntibodyMonoclonal
Armenian
Hamster
anti-Mouse CD80
Biolegend104729(dil 1/25)
AntibodyMonoclonal
Rat anti-Mouse
CD8a
Biolegend100734(dil 1/400)
AntibodyMonoclonal
Rat anti-Mouse
CD9
BD Biosciences558749(dil 1/100)
AntibodyMonoclonal
Rat anti-Mouse
CD93 (AA4.1)
eBioscience17–5892(dil 1/100)
AntibodyFCRL5PMID: 17082595_Produced in Randall Davis' lab (dil 1/400)
AntibodyPolyclonal
Sheep
anti-Mouse FCRL5
R and D SystemsFAB6756G(dil 1/50)
AntibodyMonoclonal Rat
Anti-Mouse
T- and B-Cell
Activation Antigen
GL7
BD Biosciences562080(dil 1/100)
AntibodyMonoclonal Rat
Anti-Mouse
IgD
Biolegend405725(dil 1/400)
AntibodyMonoclonal
Rat Anti-Mouse
IgD
Biolegend405723(dil 1/400)
AntibodyMonoclonal
Rat Anti-Mouse
IgD
Biolegend405710(dil 1/400)
AntibodyMonoclonal Rat
Anti-Mouse
IgG2b
Biolegend406708(dil 1/25)
AntibodyMonoclonal
Rat Anti-Mouse
IgM
Biolegend406512(dil 1/100)
Recombinant DNA reagentVDJHNIMP23
anti-MSP121
variable region
coding exon
containing the
Leader-V
segment intron
from gDNA of the
NIMP23 hybridoma
PMID: 7141700_Produced in Jean Langhorne's lab
Recombinant DNA reagentC57Bl/6 IgH
HEL variable
region
knock-in
construct
PMID: 12668643_Donated by Robert
Brink of the Garvan Institute
of Medical Research, New South Wales, Australia
Peptide, recombinant proteinMSP121PMID: 11254580_Produced in Jean Langhorne's lab
Commercial assay or kitEZ-Link
Sulfo-NHS-LC-Biotinylation
Kit
Thermo Scientific21435
Commercial assay or kitRiboPure
RNA Purification
Kit
InvitrogenAM1924
Commercial assay or kitQubit 1X
dsDNA HS
Assay Kit
InvitrogenQ33231
Commercial assay or kitSMART-Seq
v4 Ultra Low
Input RNA
Kit for Sequencing
Takara634889
Commercial assay or kitOvation
Ultralow Library
System V2
Nugen0344–32
Commercial assay or kitLIVE/DEAD
Fixable Aqua
Dead Cell Stain Kit
InvitrogenL34957
Commercial assay or kitLIVE/DEAD
Fixable Blue
Dead Cell Stain Kit
InvitrogenL23105
Chemical compound, drugStreptavidin-R-PhycoerythrinProzymePJRS25
Chemical compound, drugStreptavidin-AllophycocyaninProzymePJ27S
Chemical compound, drugTiterMax
Gold Adjuvant
Merck (formerly Sigma-Aldrich)T2684-1ML
Chemical compound, drugR848 (Resiquimod)Invivogentlrl-r848
Chemical compound, drugTRI Reagent
Solution
InvitrogenAM9738
Software, algorithmcutadapt v1.9.1doi:10.14806/ej.17.1.200
Software, algorithmRSEM v1.2.31doi:10.1186/1471-2105-12-323
Software, algorithmSTAR v2.5.1bdoi:10.1093/
bioinformatics/bts635
Software, algorithmDESeq2doi:10.1186/s13059-014-0550-8
Software, algorithmR v3.4.0otherhttps://www.r-project.org
Software, algorithmBioconductor
v3.5
otherhttp://www.
bioconductor.org
Software, algorithmBroad's
Gene Set
Enrichment
Analysis (GSEA)
otherhttp://software.broadinstitute.org/gsea/index.jsp
Software, algorithmFlowJo version 9.6 or higherTree Star
Software, algorithmCytofkitdoi:10.1371/journa
l.pcbi.1005112.s009
Software, algorithmPrism v6GraphPad

Additional files

Supplementary file 1

Mouse homologues to human genes previously described to be either up (↑) or down (↓) regulated in human atypical memory B cells (AMB).

https://doi.org/10.7554/eLife.39800.016
Supplementary file 2

List of top 50 Reactome gene sets yielding the highest normalized enrichment score (NES) by GSEA.

https://doi.org/10.7554/eLife.39800.017
Transparent reporting form
https://doi.org/10.7554/eLife.39800.018

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