Isolation of CD4+ T-cells and Analysis of Circulating T-follicular Helper (cTfh) Cell Subsets from Peripheral Blood Using 6-color Flow Cytometry

Summary

Here, a protocol for the isolation and characterization of CD4⁺ T-cell subsets from human peripheral blood is described. Purified CD4⁺ T-cells are analyzed by flow cytometry to determine proportions of T-follicular helper cell subsets.

Abstract

Aberrant T-follicular helper (Tfh) cell activity is detectable in autoimmune conditions and their presence is associated with clinical outcomes when the lymph node microenvironment in B-cell non-Hodgkin's lymphoma is analyzed. Subsets of circulating T-follicular helper cells (cTfh), the circulating memory compartment of Tfh cells in the blood, are also perturbed in disease and therefore represent potential novel predictive biomarkers. Peripheral blood-based testing is advantageous because it is relatively non-invasive and allows simple serial monitoring.This article describes a method for isolating CD4⁺ T-cells from human blood, and further analysis by flow-cytometry to enumerate cTfh cells and the proportions of their various subsets (cTfhPD-1^-/+/hi, cTfh1,2,17 and cTfh1/17). The level of these subsets was then compared between normal subjects and patients with lymphoma. We found that the method was robust enough to obtain reliable results from routinely collected patient material. The technique we describe for the analysis can be easily adapted to cell sorting and downstream applications such as RT-PCR.

Introduction

T-follicular helper cells (Tfh) are a CD4⁺ T-cell subset that was initially characterized in lymphoid tissues¹. These cells express PD-1 and CXCR5 surface receptors, secrete IL-21 and IL-4 and show nuclear expression of the transcription factor, BCL-6^2,3. As their name suggests, they are found in germinal centers and are essential for high affinity antibody production¹.

Dysregulated Tfh responses have been implicated in disease pathogenesis, most notably autoimmune disease, where they promote the expansion of autoreactive B ....

Protocol

Blood samples were obtained from normal subjects (NS) (n = 12) as well as patients with marginal zone lymphoma (MZL) (n = 7) and other types of B-cell non-Hodgkin's lymphoma (BNHL) (6 FL patients, 2 lymphoplasmacytic lymphoma patients and 1 low-grade B-cell non-Hodgkin's lymphoma not otherwise specified patient). Patients were recruited from the hematology clinics at Leicester Royal Infirmary after having given informed, written consent, with ethical approval in place for all studies. Ethical approval was obtaine.......

Discussion

This protocol represents a simple and efficient way to analyze peripheral blood cTfh cells, enabling the detection of all relevant subsets identified in the literature thus far. Blood samples can be easily and efficiently obtained as part of standard out-patient clinics and serial samples can be collected in parallel with clinical data. In turn, this enables prospective studies evaluating cTfh subsets as biomarkers for disease progression or response to treatment. These studies would be particularly warranted in disease .......

Materials

Name	Company	Catalog Number	Comments
RosetteSep Human CD4+ T Cell Enrichment Cocktail	STEMCELL TECHNOLOGIES	15062
Ficoll-Paque PLUS	GE Healthcare Life Sciences	17144003
BUV395 Mouse Anti-Human CD183 Clone 1C6/CXCR3	BD Horizon	565223
BV711 Mouse Anti-Human CD196 (CCR6) Clone 11A9	BD Horizon	563923
BV421 Rat Anti-Human CXCR5 (CD185) Clone RF8B2	BD Horizon	562747
BB515 Mouse Anti-Human CD4 Clone  RPA-T4	BD Horizon	564419
PE Mouse Anti-Human CD279 Clone MIH4	BD Pharmingen	557946
APC-H7 Mouse Anti-Human CD45RA Clone  HI100	BD Pharmingen	560674
LIVE/DEAD Fixable Far Red Dead Cell Stain Kit, for 633 or 635 nm excitation	ThermoFisher Scientific	L34973
Brilliant Stain Buffer	BD Horizon	563794
Anti-Mouse Ig, κ/Negative Control Compensation Particles Set	BD CompBead	552843
FACS Aria II Flow Cytometer	BD Biosciences	644832
FACSDiva 6.1.3	BD Biosciences	643629	Flow Cytometer Acquisition Software
FlowJo 10.2	Treestar Inc.		Flow Cytometry Data Analysis Software
Anti-CXCR3 antibody	BD Horizon	565223
Anti-CCR6 antibody	BD Horizon	563923
Anti-CXCR5 antibody	BD Horizon	562747
Anti-CD4 antibody	BD Horizon	564419
Anti-PD-1 antibody	BD Pharmingen	557946
Anti-CD45RA antibody	BD Pharmingen	560674
Viability Marker	ThermoFisher Scientific	L34973