1
Nihan Kara 1 , Mirko Corselli 2 , Tri T. Le 1 , Margaret Inokuma 1 , Noel Warner 1 , Alan Stall 2 , Suraj Saksena 1 . 1 BD Biosciences, San Jose, CA 2 BD Biosciences San Diego , CA Evaluation of Activation and Homing Markers on Regulatory T cells using the 12Color BD FACSLyric™ Flow Cytometer Poster# BD Life Sciences Visit bdbiosciences.com 2350 Qume Drive, San Jose, CA 95131 re Results 3: Evaluation of the modular 12Color T reg activation panel Fresh whole blood from healthy donors was used for peripheral blood mononuclear cell (PBMC) preparation. The PBMCs were surface stained using BD HorizonBrilliant Stain Buffer (Cat. No. 659611) with the antibodies listed below. For intracellular (IC) staining of FoxP3, BD Pharmingen™ Transcription Factor (TF) Buffer Set (Cat. No. 562574) was used. Samples were analyzed on a 12color BD FACSLyricflow cytometer, and data analysis was performed using BD FACSuite™ software. 12color modular flow cytometry panel for T reg identification (8color backbone panel) and characterization (4color activation/homing dropin panels) Correlation between CD15s expression and other markers: The results indicate a correlation between high levels of CD15s and FoxP3, and activation markers HLADR, PI16, CD147 and CD39. No correlation with CD15s was seen for CD161. 8Color Backbone Panel Fluorochrome Target Antigens 1 BV421 CD25 2 BV510 CD15s 3 FITC CD4 4 PE CD161 5 BB700 CD127 6 PECy7 CD45RA 7 AF647 FoxP3 8 APCH7 CD3 4Color Activation DropIn Panel Fluorochrome Target Antigens 1 BV605 PI16 2 BV711 CD39 3 BV786 CD147 4 APCR700 HLADR 4Color Homing DropIn Panel Fluorochrome Target Antigens 1 BV605 CD31 2 BV711 CD183 3 BV786 CD194 4 APCR700 CD196 The 4color homing dropin panel helps identify recent thymic emigrants (RTE) and T effector like subsets within the T reg population Results 2: Evaluation of the modular 12Color T reg homing panel Resolution of the 8color backbone panel for T reg identification was not impacted by the addition of 4color T reg homing or activation dropin panels significantly: The 8color backbone panel helps identify T reg cells as CD3 + CD4 + CD127 low CD25 high FoxP3 + cells, and further characterize them as naïve (CD45RA + ), effector suppressive (CD45RA CD15s + ) 1 or proinflammatory cytokine secreting (CD45RA CD161 + )T reg cell subsets 2,3 . There is minimal impact in resolution and population percentage of major T reg subsets upon addition of 4color homing or activation drop ins. 1. Miyara M, Chader D, Sage E, Sugiyama D, Nishikawa H, Bouvry D, Claër L, Hingorani R, Balderas R, Rohrer J, Warner N, Chapelier A, Valeyre D, Kannagi R, Sakaguchi S, Amoura Z, Gorochov G. Sialyl Lewis x (CD15s) identifies highly differentiated and most suppressive FOXP3high regulatory T cells in humans. PNAS. 2015 Jun 9;112(23):72257230. 2. Pesenacker AM, Bending D, Ursu S, Wu Q, Nistala K, Wedderburn LR. CD161 defines the subset of FoxP3+ T cells capable of producing proinflammatory cytokines. Blood. 2013 Apr 4;121(14):26472658. 3. Afzali B, Mitchell PJ, Edozie FC, Povoleri GA, Dowson SE, Demandt L, Walter G, Canavan JB, Scotta C, Menon B, Chana PS, Khamri W, Kordasti SY, Heck S, Grimbacher B, Tree T, Cope AP, Taams LS, Lechler RI, John S, Lombardi G. CD161 expression characterizes a subpopulation of human regulatory T cells that produces IL17 in a STAT3dependent manner. Eur J Immunol. 2013 Aug;43(8):20432054. Class 1 Laser Product. For In Vitro Diagnostic Use. Cy™ is a trademark of GE Healthcare. © 2017 BD. BD, the BD Logo and all other trademarks are property of Becton, Dickinson and Company. 231996000 The 12color T reg activation panel reveals donor specific differences in the interplay between activation markers Lymphocytes CD3 + CD4 + CD25 high CD127 low FoxP3 + Tregs FoxP3 + Tregs CD4 FITC CD127 BB700 Count CD15s BV510 CD161 PE CD3 + CD4 + 52.3% CD25 high CD127 low 7.3% FoxP3 19.3% FoxP3 + Treg 76.4% 40.4% 19.6% 39.0% 1.1% 9.3% 51.0% 0.6% 39.2% CD4 FITC CD127 BB700 Count CD15s BV510 CD161 PE CD3 + CD4 + 52.8% CD25 high CD127 low 7.8% FoxP3 20.7% FoxP3 + Treg 75.2% 40.1% 17.2% 40.8% 1.9% 8.3% 49.4% 0.9% 41.2% CD3 APCH7 CD25 BV421 FoxP3 Alexa647 CD45RA PECy7 CD45RA PECy7 CD4 FITC CD127 BB700 Count CD15s BV510 CD161 PE FoxP3 + Treg 76.6% CD25 high CD127 low 7.6% CD3 + CD4 + 52.0% FoxP3 19.0% 38.5% 21.6% 36.6% 1.4% 8.4% 52.1% 0.7% 38.8% + Activation Dropin +Homing Dropin 8–Color Backbone References The 8color backbone panel reported here enables high resolution identification of the T reg compartment and subpopulations therein. Supplementation of the backbone with 4color dropin panel(s) for activation or homing markers enables deeper characterization of T reg subsets without any significant impact on the resolution of parent populations. Addition of the 4color homing dropin panel enabled identification of recent thymic emigrant T reg cells within the naïve T reg population as well as Teffector like subsets within the effector T reg population as reported previously 4 . Addition of the 4color activation dropin panel enabled identification of a previously reported highly immunosuppressive subpopulation expressing high levels of CD15s, HLADR, PI16, CD147 and CD39 within CD45RA effector T reg population 13, 59 . Furthermore, our 12color assay was able to pick up variations in donorspecific counts of T reg subsets. Overall, by combining multiple markers in a single tube this 12color modular flow cytometry assay on BD FACS Lyric system enables researchers to study different facets of T reg biology, such as homing, activation, proliferation, maturation, stability in the context of a workflow optimized for ease of use (time and cost). Conclusions: 4. Duhen T, Duhen R, Lanzavecchia A, Sallusto F, Campbell DJ. Functionally distinct subsets of human FOXP3+ Treg cells that phenotypically mirror effector Th cells. Blood. 2012 May 10;119(19):44304440. 5. Nicholson IC, Mavrangelos C, Bird DR, BresatzAtkins S, EastaffLeung NG, Grose RH, Gundsambuu B, Hill D, Millard DJ, Sadlon TJ, To S, Zola H, Barry SC, Krumbiegel D. PI16 is expressed by a subset of human memory Treg with enhanced migration to CCL17 and CCL20. Cell Immunol. 2012 JanFeb;275(12):128. 6. Solstad T, Bains SJ, Landskron J, Aandahl EM, Thiede B, Taskén K, Torgersen KM. CD147 (Basigin/Emmprin) identifies FoxP3+CD45RO+CTLA4+activated human regulatory T cells. Blood. 2011 Nov 10;118(19):514151. 7. BaecherAllan C, Wolf E, Hafler DA. MHC class II expression identifies functionally distinct human regulatory T cells. J Immunol. 2006 Apr 15;176(8):46224631. 8. Schaier M, Seissler N, Schmitt E, Meuer S, Hug F, Zeier M, Steinborn A. DRhigh+CD45RATregs potentially affect the suppressive activity of the total Treg pool in renal transplant patients. PLoS ONE. 2012 7(3): e34208. SSC CD45RA PECy7 FoxP3 + Tregs CD45RA CD45RA + CD31 BV605 CD45RA PECy7 CD45RA + Tregs RTE CD45RA Tregs CD45RA PECy7 CD183 BV711 Th1like CD196 APCR700 CD194 BV786 CD183 Tregs Th17/Th22like Th2like Abstract M -1020 102 103 104 105 0 0.5 1 M -1020 102 103 104 105 0 0.5 1 M -1020 102 103 104 105 0 0.5 1 M -1020 102 103 104 105 0 0.5 1 M -102 0102 103 104 105 0 0.5 1 M -1020 102 103 104 105 0 0.5 1 CD15s BV510 CD45RA PECy7 FoxP3 + Tregs FoxP3 CD147 HLADR CD39 PI16 CD161 MFI of Positive MFI of Positive MFI of Positive MFI of Positive MFI of Positive MFI of Positive Normalized Normalized Normalized Normalized Normalized Normalized Donor 3 All Donors Donor 3 All Donors CD15s BV510 CD15s BV510 CD15s BV510 HLADR APCR700 CD147 BV786 CD39 BV711 Donor 1 Donor 2 Donor 3 FoxP3 + Tregs FoxP3 + Tregs FoxP3 + Tregs Methods Results 1. Resolution of the 8color plus 4color modular panel Introduction Results 3. Evaluation of the modular 12color T reg activation panel Results 2. Evaluation of the modular 12color T reg homing panel Conclusions Min Max % Parent Population Donor 1 Donor 2 Donor 3 CD39 + CD15s 5.1 5.5 19.6 CD15s + 12.7 8.5 35.2 (12) CD39 CD15s 37.0 55.9 39.6 CD15s + 45.1 30.1 5.7 CD147 + CD15s 43.2 62.3 59.9 CD15s + 56.8 37.7 40.1 HLADR + CD15s 12.1 15.5 6.2 CD15s + 47.0 32.1 26.6 HLADR CD15s 31.0 46.6 53.6 CD15s + 9.9 5.8 13.7 Deeper understanding of regulatory T cell (T reg ) biology is critical for the successful development of therapeutic and diagnostic applications. T reg heterogeneity in terms of phenotype, function, and distribution is widely documented, thereby making a more detailed characterization of these cells critical for downstream applications. Several reports have identified distinct T reg immunophenotypic signatures correlating with different biological functions including activation and tissue homing 19 . Furthermore, others have combined high parameter mass cytometry approaches with high dimensional data analysis tools to reveal additional heterogeneity within the human T reg compartment 10,11 . Here, we report the development and utility of a more conventional flow cytometry based assay to explore T reg heterogeneity. We developed an 8color backbone plus 4color dropin modular flow cytometry assay to identify and characterize T reg subsets in greater depth. Specifically, we developed two different T reg characterization dropin panels to explore two critical facets of T reg biology: Homing (CD31, CD183, CD194 and CD196) Activation (PI16, CD39, CD147 and HLADR) The 8color backbone panel enabled clear identification of CD3 + CD4 + CD127 low/neg CD25 + FoxP3 + T reg cells, and further categorized as CD45RA + (naïve) and CD45RA (effector) subsets. The inclusion of CD15s and CD161 in the backbone panel enabled identification of functionally suppressive effector 1 and/or proinflammatory cytokinesecreting 2,3 T reg cells within the heterogeneous CD45RA population, respectively. The markers in the homing dropin panel helped us identify recent thymic emigrants within the naïve T reg cell population, and T effector like T reg subsets based on a gating strategy that has been shown previously 4 . Simultaneous assessment of the markers in the activation panel enabled us to study the correlation between them. Our 12color activation panel recapitulates some of the earlier observations and more importantly expands the knowledge of the interplay of activation markers with the inclusion of CD15s and PI16. Overall, our results highlight an interesting interplay between different T reg markers, their putative biological function, and the underlying heterogeneity within the T reg population. Altogether, this modular 12color flow cytometry assay presents a new approach to enable deeper and more comprehensive analysis of different aspects of T reg biology in a simplified workflow. 9. Borsellino G, Kleinewietfeld M, Di Mitri D, Sternjak A, Diamantini A, Giometto R, Höpner S, Centonze D, Bernardi G, Dell'Acqua ML, Rossini PM, Battistini L, Rötzschke O, Falk K. Expression of ectonucleotidase CD39 by Foxp3+ Treg cells: hydrolysis of extracellular ATP and immune suppression. Blood. 2007 Aug 15;110(4):122532. 10.Mason GM, Lowe K, Melchiotti R, Ellis R, de Rinaldis E, Peakman M, Heck S, Lombardi G, Tree TI. Phenotypic complexity of the human regulatory T cell compartment revealed by mass cytometry. J Immunol. 2015 Sep 1;195(5):20307. 11.Konrad M, Simonds E, Bendall S, George T and Delucchi P. Analysis of mass cytometry data with viSNE reveals phenotypic heterogeneity within human Tregs. J Immunol May 1, 2014, 192 (1 Supplement) 69.22; (Immunology2014). 12.Rissiek A, Baumann I, Cuapio A, Mautner A, Kolster M, Arck PC, DodgeKhatami A, Mittrücker HW, KochNolte F, Haag F, Tolosa E. The expression of CD39 on regulatory T cells is genetically driven and further upregulated at sites of inflammation. J Autoimmun. 2015 Apr;58:1220. doi: 10.1016/j.jaut.2014.12.007. Epub 2015 Jan 29.

Activation Homing Markers Regulatory T cells using the

  • Upload
    others

  • View
    5

  • Download
    0

Embed Size (px)

Citation preview

Page 1: Activation Homing Markers Regulatory T cells using the

Nihan Kara1, Mirko Corselli2, Tri T. Le1, Margaret Inokuma1, Noel Warner1, Alan Stall2, Suraj Saksena1.1BD Biosciences, San Jose, CA 2BD Biosciences San Diego , CA

Evaluation of Activation and Homing Markers on Regulatory T cells using the 12‐Color BD FACSLyric™ Flow Cytometer

Poster#

BD Life Sciences Visit bdbiosciences.com2350 Qume Drive, San Jose, CA 95131

re 

Results 3: Evaluation of the modular 12‐Color Treg activation panel

Fresh whole blood from healthy donors was used for peripheral blood mononuclear cell (PBMC) preparation. The PBMCs were surface stained using BD Horizon™Brilliant Stain Buffer (Cat. No. 659611) with the antibodies listed below. For intracellular (IC) staining of FoxP3, BD Pharmingen™ Transcription Factor (TF) Buffer Set (Cat. No. 562574) was used. Samples were analyzed on a 12‐color BD FACSLyric™ flow cytometer, and data analysis was performed using BD FACSuite™ software.

12‐color modular flow cytometry panel for Treg identification (8‐color backbone panel) and characterization (4‐color activation/homing drop‐in panels)

Correlation between CD15s expression and other markers:The results indicate a correlation between high levels of CD15s and FoxP3, and activation markers HLA‐DR, PI16, CD147 and CD39. No correlation with CD15s was seen for CD161.

8‐Color Backbone Panel

Fluorochrome

Target

Antigens

1 BV421 CD25

2 BV510 CD15s

3 FITC CD4

4 PE CD161

5 BB700 CD127

6 PE‐Cy7 CD45RA

7 AF647 FoxP3

8 APC‐H7 CD3

4‐Color Activation Drop‐In Panel

Fluorochrome

Target

Antigens

1 BV605 PI16

2 BV711 CD39

3 BV786 CD147

4 APC‐R700 HLA‐DR

4‐Color Homing Drop‐In Panel

Fluorochrome

Target

Antigens

1 BV605 CD31

2 BV711 CD183

3 BV786 CD194

4 APC‐R700 CD196

The 4‐color homing drop‐in panel helps identify recent thymic emigrants (RTE) and Teffector‐like subsets within the Tregpopulation

Results 2: Evaluation of the modular 12‐Color Treg homing panel

Resolution of the 8‐color backbone panel for Treg identification was not impacted by theaddition of 4‐color Treg homing or activation drop‐in panels significantly:The 8‐color backbone panel helps identify Treg cells as CD3

+ CD4+ CD127low CD25high FoxP3+ cells, and further characterize them as naïve (CD45RA+), effector suppressive (CD45RA– CD15s+)1 or pro‐inflammatory cytokine secreting (CD45RA–CD161+) Treg cell subsets 

2,3.  There is minimal impact in resolution and population percentage of major Treg subsets upon addition of 4‐color homing or activation drop ins.

1.MiyaraM, Chader D, Sage E, Sugiyama D, Nishikawa H, Bouvry D, Claër L, Hingorani R, Balderas R, Rohrer J, Warner N, Chapelier A, Valeyre D, Kannagi R, Sakaguchi S, Amoura Z, Gorochov G. Sialyl Lewis x (CD15s) identifies highly differentiated and most suppressive FOXP3high regulatory T cells in humans. PNAS. 2015 Jun 9;112(23):7225‐7230. 

2.Pesenacker AM, Bending D, Ursu S, Wu Q, Nistala K, Wedderburn LR. CD161 defines the subset of FoxP3+ T cells capable of producing proinflammatory cytokines. Blood. 2013 Apr 4;121(14):2647‐2658.

3.Afzali B, Mitchell PJ, Edozie FC, Povoleri GA, Dowson SE, Demandt L, Walter G, Canavan JB, Scotta C, Menon B, Chana PS, Khamri W, Kordasti SY, Heck S, Grimbacher B, Tree T, Cope AP, Taams LS, Lechler RI, John S, Lombardi G. CD161 expression characterizes a subpopulation of human regulatory T cells that produces IL‐17 in a STAT3‐dependent manner. Eur J Immunol. 2013 Aug;43(8):2043‐2054.

Class 1 Laser Product. For In Vitro Diagnostic Use.Cy™ is a trademark of GE Healthcare. © 2017 BD. BD, the BD Logo and all other trademarks are property of Becton, Dickinson and Company. 23‐19960‐00

The 12‐color Treg activation panel reveals donor specific differences in the interplay between activation markers

Lymphocytes                    CD3+ CD4+   CD25high CD127low  FoxP3+ Tregs                   FoxP3+ Tregs

CD4 FITC

CD127 BB700

Count

CD15s BV510

CD161 PE

CD3+ CD4+

52.3% CD25high 

CD127low

7.3%

FoxP3–

19.3%

FoxP3+ Treg76.4%

40.4%

19.6% 39.0%

1.1% 9.3%

51.0%

0.6%

39.2%

CD4 FITC

CD127 BB700

Count

CD15s BV510

CD161 PE

CD3+ CD4+

52.8% CD25high 

CD127low 

7.8%

FoxP3–

20.7%

FoxP3+ Treg 75.2%

40.1%

17.2% 40.8%

1.9% 8.3%

49.4%

0.9%

41.2%

CD3 APC‐H7                     CD25 BV421                           FoxP3 Alexa‐647                       CD45RA PE‐Cy7              CD45RA PE‐Cy7

CD4 FITC

CD127 BB700

Count

CD15s BV510

CD161 PE

FoxP3+ Treg76.6%CD25high 

CD127low

7.6%

CD3+ CD4+

52.0%

FoxP3–

19.0%

38.5%

21.6% 36.6%

1.4% 8.4%

52.1%

0.7%

38.8%

+ Activation Drop‐in         +H

oming Drop‐in             8–Color Backbone

References

• The 8‐color backbone panel reported here enables high resolution identification of the Treg compartment and subpopulations therein.

• Supplementation of the backbone with 4‐color drop‐in panel(s) for activation or homing markers enables deeper characterization of Treg subsets without any significant impact on the resolution of parent populations.

• Addition of the 4‐color homing drop‐in panel enabled identification of recent thymic emigrant Treg cells within the naïve Treg population as well as T‐effector like subsets within the effector Treg population as reported previously

4.

• Addition of the 4‐color activation drop‐in panel enabled identification of a previously reported highly immunosuppressive subpopulation  expressing high levels of CD15s, HLA‐DR, PI‐16, CD147 and CD39 within CD45RA– effector Treg population

1‐3, 5‐9. Furthermore, our 12‐color assay was able to pick up variations in donor‐specific counts of Treg subsets. 

• Overall, by combining multiple markers in a single tube this 12‐color modular flow cytometry assay on BD FACS Lyric system enables researchers to study different facets of Treg biology, such as homing, activation, proliferation, maturation, stability in the context of a workflow optimized for ease of use (time and cost). 

Conclusions:

4.Duhen T, Duhen R, Lanzavecchia A, Sallusto F, Campbell DJ. Functionally distinct subsets of human FOXP3+ Treg cells that phenotypically mirror effector Th cells.Blood. 2012 May 10;119(19):4430‐4440.

5.Nicholson IC, Mavrangelos C, Bird DR, Bresatz‐Atkins S, Eastaff‐Leung NG, Grose RH, Gundsambuu B, Hill D, Millard DJ, Sadlon TJ, To S, Zola H, Barry SC, Krumbiegel D. PI16 is expressed by a subset of human memory Treg with enhanced migration to CCL17 and CCL20. Cell Immunol. 2012 Jan‐Feb;275(1‐2):12‐8.

6. Solstad T, Bains SJ, Landskron J, Aandahl EM, Thiede B, Taskén K, Torgersen KM. CD147 (Basigin/Emmprin) identifies FoxP3+CD45RO+CTLA4+‐activated human regulatory T cells. Blood. 2011 Nov 10;118(19):5141‐51. 

7.Baecher‐Allan C, Wolf E, Hafler DA. MHC class II expression identifies functionally distinct human regulatory T cells. J Immunol. 2006 Apr 15;176(8):4622‐4631.8. Schaier M, Seissler N, Schmitt E, Meuer S, Hug F, Zeier M, Steinborn A. DRhigh+CD45RA−Tregs potentially affect the suppressive activity of the total Treg pool in renal transplant patients. PLoS ONE. 2012 7(3): e34208. 

SSC

CD45RA PE‐Cy7

FoxP3+ Tregs

CD45RA‐ CD45RA+

CD31 BV605

CD45RA PE‐Cy7

CD45RA+ Tregs

RTE

CD45RA– Tregs

CD45RA PE‐Cy7

CD183 BV711

Th1‐like

CD196 APC‐R700

CD194 BV786

CD183– Tregs

Th17/Th22‐like

Th2‐like

Abstract

M

-1020 102 103 104 1050

0.5

1

M

-1020 102 103 104 1050

0.5

1

M

-1020 102 103 104 1050

0.5

1

M

-1020 102 103 104 1050

0.5

1

M

-1020102 103 104 1050

0.5

1

M

-1020 102 103 104 1050

0.5

1

CD15s BV510

CD45RA PE‐Cy7

FoxP3+ Tregs

FoxP3 CD147

HLA‐DR CD39

PI16 CD161

MFI of Positive

MFI of Positive

MFI of Positive

MFI of Positive

MFI of Positive

MFI of Positive

Norm

alized

Norm

alized

Norm

alized

Norm

alized

Norm

alized

Norm

alized

Donor 3                        All Donors Donor 3                        All Donors

CD15s BV510              CD15s BV510                  CD15s BV510

HLA

‐DR APC‐R700          CD147 BV786                CD39 BV711

Donor 1                Donor 2              Donor 3FoxP3+ Tregs                  FoxP3+ Tregs                  FoxP3+ Tregs

Methods

Results 1. Resolution of the 8‐color plus 4‐color modular panel

Introduction

Results 3. Evaluation of the modular 12‐color Treg activation panel

Results 2. Evaluation of the modular 12‐color Treg homing panel

Conclusions

Min

Max

% ParentPopulation Donor 1 Donor 2 Donor 3

CD39+CD15s– 5.1 5.5 19.6CD15s+ 12.7 8.5 35.2(12)

CD39–CD15s– 37.0 55.9 39.6CD15s+ 45.1 30.1 5.7

CD147+CD15s– 43.2 62.3 59.9CD15s+ 56.8 37.7 40.1

HLA‐DR+ CD15s– 12.1 15.5 6.2CD15s+ 47.0 32.1 26.6

HLA‐DR– CD15s– 31.0 46.6 53.6CD15s+ 9.9 5.8 13.7

Deeper understanding of regulatory T cell (Treg) biology is critical for the successful development of therapeutic and diagnostic applications. Treg heterogeneity in terms of phenotype, function, and distribution is widely documented, thereby making a more detailed characterization of these cells critical for downstream applications. Several reports have identified distinct Treg immunophenotypic signatures correlating with different biological functions including activation and tissue homing1‐9. Furthermore, others have combined high parameter mass cytometry approaches with high dimensional data analysis tools to reveal additional heterogeneity within the human Treg compartment10,11. Here, we report the development and utility of a more conventional flow cytometry based assay to explore Treg heterogeneity. We developed an 8‐color backbone plus 4‐color drop‐in modular flow cytometry assay to identify and characterize Treg subsets in greater depth. Specifically, we developed two different Treg characterization drop‐in panels to explore two critical facets of Treg biology:

• Homing (CD31, CD183, CD194 and CD196)• Activation (PI16, CD39, CD147 and HLA‐DR)

The 8‐color backbone panel enabled clear identification of CD3+CD4+CD127low/negCD25+FoxP3+ Treg cells, and  further categorized as CD45RA+ (naïve) and CD45RA– (effector) subsets. The inclusion of CD15s and CD161 in the backbone panel enabled identification of functionally suppressive effector1 and/or pro‐inflammatory cytokine‐secreting 2,3 Treg cells within the heterogeneous CD45RA

–population, respectively.

The markers in the homing drop‐in panel helped us identify recent thymic emigrants within the naïve Treg cell population, and Teffector‐like Treg subsets based on a gating strategy that has been shown previously

4.  Simultaneous assessment of the markers in the activation panel enabled us to study the correlation between them. Our 12‐color activation panel recapitulates some of the earlier observations and more importantly expands the knowledge of the interplay of activation markers with the inclusion of CD15s and PI‐16.

Overall, our results highlight an interesting interplay between different Treg markers, their putative biological function, and the underlying heterogeneity within the Treg population. Altogether, this modular 12‐color flow cytometry assay presents a new approach to enable deeper and more comprehensive analysis of different aspects of Treg biology in a simplified workflow. 

9. Borsellino G, KleinewietfeldM, Di Mitri D, Sternjak A, Diamantini A, Giometto R, Höpner S, Centonze D, Bernardi G, Dell'Acqua ML, Rossini PM, Battistini L, RötzschkeO, Falk K. Expression of ectonucleotidase CD39 by Foxp3+ Treg cells: hydrolysis of extracellular ATP and immune suppression. Blood. 2007 Aug 15;110(4):1225‐32.

10.Mason GM, Lowe K, Melchiotti R, Ellis R, de Rinaldis E, Peakman M, Heck S, Lombardi G, Tree TI. Phenotypic complexity of the human regulatory T cell compartment revealed by mass cytometry. J Immunol. 2015 Sep 1;195(5):2030‐7.

11.Konrad M, Simonds E, Bendall S, George T and Delucchi P.  Analysis of mass cytometry data with viSNE reveals phenotypic heterogeneity within human Tregs. J ImmunolMay 1, 2014, 192 (1 Supplement) 69.22; (Immunology 2014).

12.Rissiek A, Baumann I, Cuapio A, Mautner A, Kolster M, Arck PC, Dodge‐Khatami A, Mittrücker HW, Koch‐Nolte F, Haag F, Tolosa E. The expression of CD39 on regulatory T cells is genetically driven and further upregulated at sites of inflammation. J Autoimmun. 2015 Apr;58:12‐20. doi: 10.1016/j.jaut.2014.12.007. Epub2015 Jan 29.