Validation of an Automated Cell Counter Method for HLA-DR and CD3 Expression in Cells Obtained from Low Volume Human Tears

<b>Background/Objectives</b>: Tears are a promising source of biomarkers reflecting both ocular and systemic conditions. However, small sample volumes and low cell yields pose technical challenges in analytical workflows. This study aimed to evaluate the feasibility of quantifying total...

Full description

Saved in:
Bibliographic Details
Main Authors: Carmen Ciavarella, Annalisa Astolfi, Chiara Coslovi, Michele Potenza, Gianandrea Pasquinelli, Luigi Fontana, Piera Versura
Format: Article
Language:English
Published: MDPI AG 2025-04-01
Series:Diagnostics
Subjects:
Online Access:https://www.mdpi.com/2075-4418/15/9/1124
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850278788804378624
author Carmen Ciavarella
Annalisa Astolfi
Chiara Coslovi
Michele Potenza
Gianandrea Pasquinelli
Luigi Fontana
Piera Versura
author_facet Carmen Ciavarella
Annalisa Astolfi
Chiara Coslovi
Michele Potenza
Gianandrea Pasquinelli
Luigi Fontana
Piera Versura
author_sort Carmen Ciavarella
collection DOAJ
description <b>Background/Objectives</b>: Tears are a promising source of biomarkers reflecting both ocular and systemic conditions. However, small sample volumes and low cell yields pose technical challenges in analytical workflows. This study aimed to evaluate the feasibility of quantifying total cell counts and characterizing HLA-DR and CD3 expression in tear-derived cells using an automated cell counter with fluorescence detection (Countess 3 FL). <b>Methods</b>: Tears were collected from 31 patients, centrifuged and the resulting pellet was incubated with HLA-DR and CD3 antibodies, markers of inflammation and T lymphocytes, respectively. Data obtained from Countess 3 FL were compared with conventional flow cytometry and immunofluorescence. For technical performance analysis, precision and reproducibility of cell count and staining were measured. For method validation, an in vitro model of hyperosmolar stress was assessed by culturing conjunctival epithelial cells (CCL20.2) with 350 or 450 mOsm NaCl. <b>Results</b>: The total cell yield in each tear sample correlated with the tear surnatant volume, in a range of 1–40μL (mean total cell number: 1.3 ± 1.1 × 10<sup>4</sup>, correlation analysis with tear volume: r = 0.47, <i>p</i> < 0.05). HLA-DR and CD3 were detected in all samples, with a mean value, respectively, of 43.6% (±21.0) and 25.0% (±15.0) intensity. Data were comparable to those obtained from standard flow cytometry analysis.HLA-DR increase in CCL20.2 exposed to hyperosmolar stress was recorded using Countess 3FL reading, confirming the detection capacity of the proposed method. <b>Conclusions</b>: The automated cell counter can provide HLA-DR and CD3 quantification in tear cell samples, despite the high variability and the low volume availability of tear samples. Method standardization and technical improvements are necessary to strengthen this application in the clinical setting.
format Article
id doaj-art-acbc7f7d00a94e6e8ecf51b94ef8771f
institution OA Journals
issn 2075-4418
language English
publishDate 2025-04-01
publisher MDPI AG
record_format Article
series Diagnostics
spelling doaj-art-acbc7f7d00a94e6e8ecf51b94ef8771f2025-08-20T01:49:20ZengMDPI AGDiagnostics2075-44182025-04-01159112410.3390/diagnostics15091124Validation of an Automated Cell Counter Method for HLA-DR and CD3 Expression in Cells Obtained from Low Volume Human TearsCarmen Ciavarella0Annalisa Astolfi1Chiara Coslovi2Michele Potenza3Gianandrea Pasquinelli4Luigi Fontana5Piera Versura6DIMEC, Department of Surgical and Medical Sciences, Alma Mater Studiorum University of Bologna, 40138 Bologna, ItalyDIMEC, Department of Surgical and Medical Sciences, Alma Mater Studiorum University of Bologna, 40138 Bologna, ItalyIRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, ItalyDIMEC, Department of Surgical and Medical Sciences, Alma Mater Studiorum University of Bologna, 40138 Bologna, ItalyDIMEC, Department of Surgical and Medical Sciences, Alma Mater Studiorum University of Bologna, 40138 Bologna, ItalyIRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, ItalyIRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy<b>Background/Objectives</b>: Tears are a promising source of biomarkers reflecting both ocular and systemic conditions. However, small sample volumes and low cell yields pose technical challenges in analytical workflows. This study aimed to evaluate the feasibility of quantifying total cell counts and characterizing HLA-DR and CD3 expression in tear-derived cells using an automated cell counter with fluorescence detection (Countess 3 FL). <b>Methods</b>: Tears were collected from 31 patients, centrifuged and the resulting pellet was incubated with HLA-DR and CD3 antibodies, markers of inflammation and T lymphocytes, respectively. Data obtained from Countess 3 FL were compared with conventional flow cytometry and immunofluorescence. For technical performance analysis, precision and reproducibility of cell count and staining were measured. For method validation, an in vitro model of hyperosmolar stress was assessed by culturing conjunctival epithelial cells (CCL20.2) with 350 or 450 mOsm NaCl. <b>Results</b>: The total cell yield in each tear sample correlated with the tear surnatant volume, in a range of 1–40μL (mean total cell number: 1.3 ± 1.1 × 10<sup>4</sup>, correlation analysis with tear volume: r = 0.47, <i>p</i> < 0.05). HLA-DR and CD3 were detected in all samples, with a mean value, respectively, of 43.6% (±21.0) and 25.0% (±15.0) intensity. Data were comparable to those obtained from standard flow cytometry analysis.HLA-DR increase in CCL20.2 exposed to hyperosmolar stress was recorded using Countess 3FL reading, confirming the detection capacity of the proposed method. <b>Conclusions</b>: The automated cell counter can provide HLA-DR and CD3 quantification in tear cell samples, despite the high variability and the low volume availability of tear samples. Method standardization and technical improvements are necessary to strengthen this application in the clinical setting.https://www.mdpi.com/2075-4418/15/9/1124tearsinflammationmicroquantities volumeautomated cell counter
spellingShingle Carmen Ciavarella
Annalisa Astolfi
Chiara Coslovi
Michele Potenza
Gianandrea Pasquinelli
Luigi Fontana
Piera Versura
Validation of an Automated Cell Counter Method for HLA-DR and CD3 Expression in Cells Obtained from Low Volume Human Tears
Diagnostics
tears
inflammation
microquantities volume
automated cell counter
title Validation of an Automated Cell Counter Method for HLA-DR and CD3 Expression in Cells Obtained from Low Volume Human Tears
title_full Validation of an Automated Cell Counter Method for HLA-DR and CD3 Expression in Cells Obtained from Low Volume Human Tears
title_fullStr Validation of an Automated Cell Counter Method for HLA-DR and CD3 Expression in Cells Obtained from Low Volume Human Tears
title_full_unstemmed Validation of an Automated Cell Counter Method for HLA-DR and CD3 Expression in Cells Obtained from Low Volume Human Tears
title_short Validation of an Automated Cell Counter Method for HLA-DR and CD3 Expression in Cells Obtained from Low Volume Human Tears
title_sort validation of an automated cell counter method for hla dr and cd3 expression in cells obtained from low volume human tears
topic tears
inflammation
microquantities volume
automated cell counter
url https://www.mdpi.com/2075-4418/15/9/1124
work_keys_str_mv AT carmenciavarella validationofanautomatedcellcountermethodforhladrandcd3expressionincellsobtainedfromlowvolumehumantears
AT annalisaastolfi validationofanautomatedcellcountermethodforhladrandcd3expressionincellsobtainedfromlowvolumehumantears
AT chiaracoslovi validationofanautomatedcellcountermethodforhladrandcd3expressionincellsobtainedfromlowvolumehumantears
AT michelepotenza validationofanautomatedcellcountermethodforhladrandcd3expressionincellsobtainedfromlowvolumehumantears
AT gianandreapasquinelli validationofanautomatedcellcountermethodforhladrandcd3expressionincellsobtainedfromlowvolumehumantears
AT luigifontana validationofanautomatedcellcountermethodforhladrandcd3expressionincellsobtainedfromlowvolumehumantears
AT pieraversura validationofanautomatedcellcountermethodforhladrandcd3expressionincellsobtainedfromlowvolumehumantears