Elevated CD3low double negative T lymphocyte is associated with pneumonia and its severity in pediatric patients

Artificial intelligence-based analysis of tumor-infiltrating lymphocyte spatial distribution for colorectal cancer prognosis

BACKGROUND

Artificial intelligence (AI) technology represented by deep learning has made remarkable achievements in digital pathology, enhancing the accuracy and reliability of diagnosis and prognosis evaluation. The spatial distribution of CD3 + and CD8 + T cells within the tumor microenvironment has been demonstrated to have a significant impact on the prognosis of colorectal cancer (CRC). This study aimed to investigate CD3 CT (CD3 + T cells density in the core of the tumor [CT]) prognostic ability in patients with CRC by using AI technology.

METHODS

The study involved the enrollment of 492 patients from two distinct medical centers, with 358 patients assigned to the training cohort and an additional 134 patients allocated to the validation cohort. To facilitate tissue segmentation and T-cells quantification in whole-slide images (WSIs), a fully automated workflow based on deep learning was devised. Upon the completion of tissue segmentation and subsequent cell segmentation, a comprehensive analysis was conducted.

RESULTS

The evaluation of various positive T cell densities revealed comparable discriminatory ability between CD3 CT and CD3-CD8 (the combination of CD3 + and CD8 + T cells density within the CT and invasive margin) in predicting mortality (C-index in training cohort: 0.65 vs. 0.64; validation cohort: 0.69 vs. 0.69). The CD3 CT was confirmed as an independent prognostic factor, with high CD3 CT density associated with increased overall survival (OS) in the training cohort (hazard ratio [HR] = 0.22, 95% confidence interval [CI]: 0.12-0.38, P <0.001) and validation cohort (HR = 0.21, 95% CI: 0.05-0.92, P = 0.037).

CONCLUSIONS

We quantify the spatial distribution of CD3 + and CD8 + T cells within tissue regions in WSIs using AI technology. The CD3 CT confirmed as a stage-independent predictor for OS in CRC patients. Moreover, CD3 CT shows promise in simplifying the CD3-CD8 system and facilitating its practical application in clinical settings.

Severity of critical illness correlates with CD3-low expression on iNKT-cells among septic surgical patients

BACKGROUND

iNKT-cells are innate regulatory lymphocytes capable of directing immune and inflammatory responses to sepsis. Repeat stimulation of iNKT-cells leads to the induction of anergy with the emergence of a hyporesponsive CD3low iNKT-cell subpopulation.

METHODS

iNKT-cells were isolated from critical ill surgical patients with sepsis and phenotyped for CD3 expression. This was correlated with degree of severity of illness, as denoted by APACHE-II score.

RESULTS

Comparing healthy volunteers to critically ill septic patients, it was noted that increasing severity of sepsis was associated with increasing frequency of circulating CD3low-iNKT-cell populations.

CONCLUSION

The emergence of CD3low -iNKT-cells may serve as a clinically translatable marker of degree of sepsis-induced immune dysfunction.

High-dimensional phenotyping of the peripheral immune response in community-acquired pneumonia

Background

Community-acquired pneumonia (CAP) represents a major health burden worldwide. Dysregulation of the immune response plays an important role in adverse outcomes in patients with CAP.

Methods

We analyzed peripheral blood mononuclear cells by 36-color spectral flow cytometry in adult patients hospitalized for CAP (n=40), matched control subjects (n=31), and patients hospitalized for COVID-19 (n=35).

Results

We identified 86 immune cell metaclusters, 19 of which (22.1%) were differentially abundant in patients with CAP versus matched controls. The most notable differences involved classical monocyte metaclusters, which were more abundant in CAP and displayed phenotypic alterations reminiscent of immunosuppression, increased susceptibility to apoptosis, and enhanced expression of chemokine receptors. Expression profiles on classical monocytes, driven by CCR7 and CXCR5, divided patients with CAP into two clusters with a distinct inflammatory response and disease course. The peripheral immune response in patients with CAP was highly similar to that in patients with COVID-19, but increased CCR7 expression on classical monocytes was only present in CAP.

Conclusion

CAP is associated with profound cellular changes in blood that mainly relate to classical monocytes and largely overlap with the immune response detected in COVID-19.

Peripheral double negative T: A look at senescent Cubans

INTRODUCTION

Age-related changes in the immune system are called immunosenescence. Within the T lymphocytes is the subpopulation of double negative (DNT) peripheral lymphocytes that are immunomodulators of the immune response, based on their ability to suppress the functions of simple positive T cells and their cytotoxicity for tumor cells and those infected by viruses.

OBJECTIVE

To determine the frequency of peripheral DNT lymphocytes in older Cuban adults.

METHODS

A cross-sectional study was carried out in 30 older adults, residents in Cuba. DNT lymphocytes in peripheral blood were quantified by flow cytometry. A Beckman Coulter Gallios flow cytometer was used for data reading and analysis. Percentage values mean and standard deviation were used. The Chi-square was used to relate the percentage values of DNT and comorbidities. It was considered statistically significant if p ≤ 0.05.

RESULTS

There was a predominance of women who represented 70 %. No older adult with low values of DNT lymphocytes was reported. Women with high percentage and absolute values of DNT lymphocytes prevailed in relation to men. In the group ≥80 years, high values in % and absolute values of DNT lymphocytes predominated. The high percentage values of DNT cells were mainly related to cardiovascular disease, and predominated in the elderly of ≥80 years old; who presented respiratory and skin infections, fundamentally. The percentage normal value in the group < 80 years was significant (p = 0.0198). The Chi-square value was 0,5995.

CONCLUSIONS

Most older adults who exhibited high percentage and absolute values of DNT lymphocytes, or a tendency to them, had some associated comorbidity, an idea that suggests that DNT cells participate in immune surveillance, defense and homeostasis based on their double identity, that is, its pathogenic or immunosuppressive phenotype according to the specific immunological microenvironment.

Double-negative T cells: Setting the stage for disease control or progression

Double-negative (DN) T cells are present at relatively low frequencies in human peripheral blood, and are characterized as expressing the alpha-beta or gamma-delta T-cell receptor (TCR), but not the CD4 nor the CD8 co-receptors. Despite their low frequencies, these cells are potent producers of cytokines and, thus, are key orchestrators of immune responses. DN T cells were initially associated with induction of peripheral immunological tolerance and immunomodulatory activities related to disease prevention. However, other studies demonstrated that these cells can also display effector functions associated with pathology development. This apparent contradiction highlighted the heterogeneity of the DN T-cell population. Here, we review phenotypic and functional characteristics of DN T cells, emphasizing their role in human diseases. The need for developing biomarkers to facilitate the translation of studies from animal models to humans will also be discussed. Finally, we will examine DN T cells as promising therapeutic targets to prevent or inhibit human disease development.