Engineered immunostimulatory cells can convert PBMCs from chronic lymphocytic leukemia (CLL) patients into potent tumor killing immune cells.

7517 Background: Alloplex Biotherapeutics has developed a cellular therapeutic that uses ENgineered Leukocyte ImmunoSTimulatory cell lines called ENLIST cells to activate and expand populations of tumor killing effector cells from human peripheral blood mononuclear cells (PBMCs). This process leads to a 300-fold expansion of NK cells, CD8+ T cells, NKT cells, and TCRγδ T cells that are called SUPLEXA cells, which will be cryopreserved and transferred back into patients as an autologous immune cell therapy for cancer. In this study, PBMCs from CLL patients were used to generate SUPLEXA cells as a first approach to comparatively profile SUPLEXA cells from cancer patients and normal healthy volunteers (NHVs). Methods: ENLIST cell lines were engineered by expressing curated immunomodulatory proteins in the SK-MEL-2 melanoma cell line. Two million (M) PBMCs from 10 CLL patients or 2 NHVs were incubated with 0.4 M freeze/thaw killed ENLIST cells for 5 days in XVIVO-15 medium with 2% heat-inactivated human AB serum (XAB2) and then split 1:15 in XAB2 containing IL-7 and IL-15 to expand. After 9 days, SUPLEXA cells were harvested and cryopreserved. Results: Original PBMCs and matched SUPLEXA cells from each donor were thawed and characterized by mass cytometry (CyTOF) using a 47-marker antibody panel. CyTOF staining results of PBMCs from CLL patients demonstrated approximately 95% leukemia cells and few T cells, NK cells, B cells, and monocytes. CyTOF staining of SUPLEXA cells from all 10 CLL patients showed expansion of NK cells (17%), CD8 T cells (11%), and CD4 T cells (7.5%) that were similar in phenotype to SUPLEXA cells from NHVs showing high expression of granzymes and perforin that are indicative of potent tumor cell killing activity. Cancer cells in the original CLL PBMC samples were reduced to 0.78%. However, a population of non-T/non-B cells (60% ± 9.5%) was detected in SUPLEXA cells from all CLL patients that require further characterization. Next, SUPLEXA cells from CLL and NHV patients were comparatively tested for tumor cell killing activity at 2:1, 1:1, and 1:2 effector to target cell (MEL-14 melanoma cells expressing RFP) ratios. Percent killing of tumor cells by SUPLEXA cells prepared from CLL patients (77.8% ± 2.6% at 2:1) and NHVs (81.5% ± 0.3% at 2:1) were nearly identical at all effector to target ratios. Conclusions: We demonstrate for the first time that PBMCs from CLL patients can be converted into SUPLEXA cells despite low numbers of normal immune cells at baseline and the known immunologic impairment present in CLL patients. Importantly, SUPLEXA cells derived from CLL patients acquire potent tumor killing activity that is indistinguishable from SUPLEXA cells prepared from NHVs. Taken together, these findings support the feasibility of converting PBMCs from CLL patients with low percentages of NK and T cells into an autologous cellular therapy for cancer.

Download Full-text

The immune cell landscape of peripheral blood mononuclear cells from PNS patients

Scientific Reports ◽

10.1038/s41598-021-92573-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Qing Ye ◽

Chao Zhou ◽

Sisi Li ◽

Jingjing Wang ◽

Fei Liu ◽

...

Keyword(s):

T Cells ◽

Nephrotic Syndrome ◽

B Cells ◽

Nk Cells ◽

Cd8 T Cells ◽

Immune Cells ◽

Peripheral Blood ◽

Mononuclear Cells ◽

Immune Cell ◽

Immunological Mechanism

AbstractExisting research suggests that the human immune system and immune cells are involved in the pathogenesis of nephrotic syndrome, but there is still a lack of direct evidence. This study tried to analyze the profiling of immune cells in the peripheral blood of steroid-sensitive nephrotic syndrome (SSNS) patients and steroid-resistant nephrotic syndrome (SRNS) patients before and after standard steroid treatment to clarify the immunological mechanism of nephrotic syndrome patients. The number and proportion of CD4 + T cells in patients with nephrotic syndrome remained unchanged. However, there is an imbalance of Th1 and Th2 and an excessive increase of Th17 cells. The number of CD8 + T cells and the number of effector CD8 + T cells in them increased significantly, but only in SSNS, the number of activated CD8 + T cells increased, and the number of activated Treg cells decreased significantly. Nephrotic syndrome patients also have B cell disorder, and it is more prominent in SSNS patients. Compared with the normal control, only the number of B cells and plasmablast in SSNS patients increased significantly (Z = − 2.20, P = 0.028). This study also observed that transitional B cells decreased in both SSNS and SRNS patients, but SSNS patients' decrease was lower than in SRNS patients. Compared with normal controls, monocytes in patients with nephrotic syndrome decreased significantly. The main reason was that Non-classical Monocyte decreased, while Classical Monocyte increased slightly. The total number of NK cells did not change, but the internal cell subgroups' composition occurred. Changes, realized as CD56hi NK cells increased, CD56low NK cells decreased; and the above trend is more evident in SSNS patients. Patients with nephrotic syndrome have immune disorders, including T cells, B cells, Monocytes, and NK cells. It can be confirmed that immune factors are involved in the pathogenesis of the nephrotic syndrome.

Download Full-text

Prognostic significance of natural killer cell-associated markers in gastric cancer: quantitative analysis using multiplex immunohistochemistry

Journal of Translational Medicine ◽

10.1186/s12967-021-03203-8 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Hee Young Na ◽

Yujun Park ◽

Soo Kyung Nam ◽

Jiwon Koh ◽

Yoonjin Kwak ◽

...

Keyword(s):

Gastric Cancer ◽

T Cells ◽

B Cells ◽

Nk Cells ◽

Natural Killer ◽

Immune Cells ◽

Nk Cell ◽

Critical Role ◽

Killer Cell ◽

Prognostic Significance

Abstract Background Natural killer (NK) cells mediate the anti-tumoral immune response as an important component of innate immunity. The aim of this study was to investigate the prognostic significance and functional implication of NK cell-associated surface receptors in gastric cancer (GC) by using multiplex immunohistochemistry (mIHC). Methods We performed an mIHC on tissue microarray slides, including 55 GC tissue samples. A total of 11 antibodies including CD57, NKG2A, CD16, HLA-E, CD3, CD20, CD45, CD68, CK, SMA, and ki-67 were used. CD45 + CD3-CD57 + cells were considered as CD57 + NK cells. Results Among CD45 + immune cells, the proportion of CD57 + NK cell was the lowest (3.8%), whereas that of CD57 + and CD57- T cells (65.5%) was the highest, followed by macrophages (25.4%), and B cells (5.3%). CD57 + NK cells constituted 20% of CD45 + CD57 + immune cells while the remaining 80% were CD57 + T cells. The expression of HLA-E in tumor cells correlated with that in tumoral T cells, B cells, and macrophages, but not CD57 + NK cells. The higher density of tumoral CD57 + NK cells and tumoral CD57 + NKG2A + NK cells was associated with inferior survival. Conclusions Although the number of CD57 + NK cells was lower than that of other immune cells, CD57 + NK cells and CD57 + NKG2A + NK cells were significantly associated with poor outcomes, suggesting that NK cell subsets play a critical role in GC progression. NK cells and their inhibitory receptor, NKG2A, may be potential targets in GC.

Download Full-text

LILRB1 Blockade Enhances Bispecific T Cell Engager Antibody–Induced Tumor Cell Killing by Effector CD8+ T Cells

The Journal of Immunology ◽

10.4049/jimmunol.1801472 ◽

2019 ◽

Vol 203 (4) ◽

pp. 1076-1087 ◽

Cited By ~ 5

Author(s):

Aeryon Kim ◽

Chia-Jung Han ◽

Ian Driver ◽

Aleksandra Olow ◽

Andrew K. Sewell ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Tumor Cell ◽

Cd8 T Cells ◽

Cell Killing ◽

Tumor Cell Killing ◽

Bispecific T Cell Engager

Download Full-text

The Complexity of Microglial Interactions With Innate and Adaptive Immune Cells in Alzheimer’s Disease

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2020.592359 ◽

2020 ◽

Vol 12 ◽

Author(s):

Season K. Wyatt-Johnson ◽

Randy R. Brutkiewicz

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

T Cells ◽

B Cells ◽

Nk Cells ◽

Immune Cells ◽

Reactive Microglia ◽

Adaptive Immune Cells ◽

Affected Relative ◽

Peripheral Immune Cells

In the naïve mouse brain, microglia and astrocytes are the most abundant immune cells; however, there is a complexity of other immune cells present including monocytes, neutrophils, and lymphocytic cells, such as natural killer (NK) cells, T cells, and B cells. In Alzheimer’s disease (AD), there is high inflammation, reactive microglia, and astrocytes, leaky blood–brain barrier, the buildup of amyloid-beta (Aβ) plaques, and neurofibrillary tangles which attract infiltrating peripheral immune cells that are interacting with the resident microglia. Limited studies have analyzed how these infiltrating immune cells contribute to the neuropathology of AD and even fewer have analyzed their interactions with the resident microglia. Understanding the complexity and dynamics of how these immune cells interact in AD will be important for identifying new and novel therapeutic targets. Thus, this review will focus on discussing our current understanding of how macrophages, neutrophils, NK cells, T cells, and B cells, alongside astrocytes, are altered in AD and what this means for the disorder, as well as how these cells are affected relative to the resident microglia.

Download Full-text

Anti-GvHD Effect of Antithymocyte Globulin Is Mediated by Antibodies Binding to T Cells and Regulatory NK Cells, and Less So or Not at All by Antibodies Binding to Other Mononuclear Cell Subsets

Blood ◽

10.1182/blood.v116.21.2346.2346 ◽

2010 ◽

Vol 116 (21) ◽

pp. 2346-2346

Author(s):

Mette Hoegh-Petersen ◽

Minaa Amin ◽

Yiping Liu ◽

Alejandra Ugarte-Torres ◽

Tyler S Williamson ◽

...

Keyword(s):

T Cells ◽

Dendritic Cells ◽

B Cells ◽

Nk Cells ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

Antithymocyte Globulin ◽

Chronic Gvhd ◽

Wilcoxon Test ◽

Effector Memory

Abstract Abstract 2346 Introduction: Polyclonal rabbit-anti-human T cell globulin may decrease the likelihood of graft-vs-host disease (GVHD) without increasing the likelihood of relapse. We have recently shown that high levels of antithymocyte globulin (ATG) capable of binding to total lymphocytes are associated with a low likelihood of acute GVHD grade 2–4 (aGVHD) as well as chronic GVHD needing systemic therapy (cGVHD) but not increased likelihood of relapse (Podgorny PJ et al, BBMT 16:915, 2010). ATG is polyclonal, composed of antibodies for antigens expressed on multiple cell subsets, including T cells, B cells, NK cells, monocytes and dendritic cells. These cell subsets may play a role in the pathogenesis of GVHD. The anti-GVHD effect of ATG may be mediated through killing/inhibition of one or several of these cell subsets (eg, T cells) or their subsets (eg, naïve T cells as based on mouse experiments naïve T cells are thought to play a major role in the pathogenesis of GVHD). To better understand the mechanism of action of ATG on GVHD, we set out to determine levels of which ATG fraction (capable of binding to which cell subset) are associated with subsequent development of GVHD. Patients and Methods: A total of 121 patients were studied, whose myeloablative conditioning included 4.5 mg/kg ATG (Thymoglobulin). Serum was collected on day 7. Using flow cytometry, levels of the following ATG fractions were determined: capable of binding to 1. naïve B cells, 2. memory B cells, 3. naïve CD4 T cells, 4. central memory (CM) CD4 T cells, 5. effector memory (EM) CD4 T cells, 6. naïve CD8 T cells, 7. CM CD8 T cells, 8. EM CD8 T cells not expressing CD45RA (EMRA-), 9. EM CD8 T cells expressing CD45RA (EMRA+), 10. cytolytic (CD16+CD56+) NK cells, 11. regulatory (CD16-CD56high) NK cells, 12. CD16+CD56− NK cells, 13. monocytes and 14. dendritic cells/dendritic cell precursors (DCs). For each ATG fraction, levels in patients with versus without aGVHD or cGVHD were compared using Mann-Whitney-Wilcoxon test. For each fraction for which the levels appeared to be significantly different (p<0.05), we determined whether patients with high fraction level had a significantly lower likelihood of aGVHD or cGVHD than patients with low fraction level (high/low cutoff level was determined from ROC curve, using the point with maximum sum of sensitivity and specificity). This was done using log-binomial regression models, ie, multivariate analysis adjusting for recipient age (continuous), stem cell source (marrow or cord blood versus blood stem cells), donor type (HLA-matched sibling versus other), donor/recipient sex (M/M versus other) and days of follow up (continuous). Results: In univariate analyses, patients developing aGVHD had significantly lower levels of the following ATG fractions: binding to naïve CD4 T cells, EM CD4 T cells, naïve CD8 T cells and regulatory NK cells. Patients developing cGVHD had significantly lower levels of the following ATG fractions: capable of binding to naïve CD4 T cells, CM CD4 T cells, EM CD4 T cells, naïve CD8 T cells and regulatory NK cells. Patients who did vs did not develop relapse had similar levels of all ATG fractions. In multivariate analyses, high levels of the following ATG fractions were significantly associated with a low likelihood of aGVHD: capable of binding to naïve CD4 T cells (relative risk=.33, p=.001), EM CD4 T cells (RR=.30, p<.001), naïve CD8 T cells (RR=.33, p=.002) and regulatory NK cells (RR=.36, p=.001). High levels of the following ATG fractions were significantly associated with a low likelihood of cGVHD: capable of binding to naïve CD4 T cells (RR=.59, p=.028), CM CD4 T cells (RR=.49, p=.009), EM CD4 T cells (RR=.51, p=.006), naïve CD8 T cells (RR=.46, p=.005) and regulatory NK cells (RR=.55, p=.036). Conclusion: For both aGVHD and cGVHD, the anti-GVHD effect with relapse-neutral effect of ATG appears to be mediated by antibodies to antigens expressed on naïve T cells (both CD4 and CD8), EM CD4 T cells and regulatory NK cells, and to a lesser degree or not at all by antibodies binding to antigens expressed on B cells, cytolytic NK cells, monocytes or DCs. This is the first step towards identifying the antibody(ies) within ATG important for the anti-GVHD effect without impacting relapse. If such antibody(ies) is (are) found in the future, it should be explored whether such antibody(ies) alone or ATG enriched for such antibody(ies) could further decrease GVHD without impacting relapse. Disclosures: No relevant conflicts of interest to declare.

Download Full-text

Deficit of Circulating CD19+CD24hiCD38hi Regulatory B Cells in Severe Aplastic Anemia

Blood ◽

10.1182/blood-2019-127053 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 1219-1219

Author(s):

Yoshitaka Zaimoku ◽

Bhavisha A Patel ◽

Sachiko Kajigaya ◽

Xingmin Feng ◽

Lemlem Alemu ◽

...

Keyword(s):

T Cells ◽

B Cells ◽

B Cell ◽

Aplastic Anemia ◽

Nk Cells ◽

Cd8 T Cells ◽

Healthy Individuals ◽

Regulatory B Cells ◽

Significant Difference ◽

Cell Phenotypes

Background: Immune aplastic anemia (AA) is caused by cytotoxic T cells (CTLs) that destroy hematopoietic stem and progenitor cells. Regulatory T cells (Tregs) are reduced in AA and increase in response to immunosuppressive therapy (IST; Solomou E et al, Blood 2007). Recent studies suggested an immune regulatory role of regulatory B cells (Bregs). Human CD19+CD24hiCD38hi Bregs suppress Th1 response of CD4+ T cells as well as IFN-γ production by CD8+ CTLs (Mauri C, Menon M, J Clin Invest 2017). The quantity and/or function of Bregs are impaired in autoimmune diseases, malignancies, chronic graft-versus-host disease, and during rejection of transplanted organs. Methods: We investigated B cell phenotypes including CD24hiCD38hi Bregs in previously untreated severe AA (SAA) and very severe AA (VSAA) patients, and healthy individuals aged 18 years and older, and tested their correlation with severity and response to IST. Absolute numbers of lymphocyte subsets, including CD19+ B cells, CD8+ T cells, CD4+ T cells, and NK cell (TBNK), were quantified in fresh blood. Percentages of B cell subsets among total CD19+ B cells, including CD24hiCD38hi Bregs, CD24loCD38lo mature naïve B cells, CD24hiCD38lo memory B cells and CD24loCD38hi plasma cells/plasmablasts, were analyzed using cryopreserved peripheral blood mononuclear cells (PBMCs). Blood samples were obtained from patients close to time of diagnosis and before institution of definitive therapy. All patients were treated with horse anti-thymocyte globulin, cyclosporine, and eltrombopag between 2012 and 2018 at the Hematology Branch, NHLBI (clinicaltrials.gov NCT01623167). Results: TBNK analysis revealed no significant difference in total B cell counts in 104 AA patients compared to 40 healthy individuals (median, 137/μl [IQR, 73-212] vs 163/μl [106-242], P=.11); NK cells were significantly decreased in patients with AA, as previously reported (Gascon P et al, Blood 1986). Total B cell count did not correlate with severity of AA (P=.89) nor with overall response at six months (P=.93). CD8+ T cells and NK cells were lower in VSAA patients compared to SAA patients. None of the TBNK subsets was predictive of overall response in six months after IST. When we assessed the phenotype of B cells among 60 AA patients whose cryopreserved PBMCs were available, CD24hiCD38hi Bregs were markedly decreased as compared to 29 healthy individuals (0.31% [0.14-0.85%] vs 1.9% [1.3-3.6%], P=3×10-7; Figure, Table), while there was no significant difference in other B cell phenotypes. Among these 60 patients, the percentage of CD24hiCD38hi Bregs was especially decreased in VSAA patients compared to SAA (0.18% [0.11-0.34%] vs 0.50% [0.17-1.4%], P=.017). In contrast, CD24loCD38lo mature naïve B cells were higher in VSAA than in SAA (69% [58-86%] vs 60% [42-70%], P=.024). CD24hiCD38hi Breg frequency was positively associated with neutrophil and reticulocyte counts (correlation coefficients [r], 0.34 and 0.26, respectively), while the frequency of CD24loCD38lo mature naïve B cells was negatively correlated (r, -0.34 and -0.40). CD24loCD38lo mature naïve B cells before IST were significantly lower in 47 patients who achieved overall responses at six months compared to 13 non-responders (64% [42-71%), vs 73% [58-88%], P=.014), but CD24hiCD38hi Breg frequency was not correlated with IST responses. At six months after IST, CD24hiCD38hi Bregs in AA patients had recovered to levels present in healthy individuals (2.3% [0.98-4.8%]), in both 34 responders and five non-responders; non-responders showed non-significant increased CD24loCD38lo mature naïve B cells at six months (P=.068). Discussion: A deficit of circulating CD24hiCD38hi Bregs in immune AA with recovery after IST, as occurs with Tregs, suggests Bregs may contribute to the immune pathophysiology in AA. We unexpectedly observed a higher percentage of CD24loCD38lo mature naïve B cells to be associated with more severe disease and a lower probability of responses to IST. B cell phenotype analysis may be beneficial for monitoring of AA and predicting outcomes of therapy. Disclosures No relevant conflicts of interest to declare.

Download Full-text

Circulating cytokines and lymphocyte subsets in patients who have recovered from COVID-19

10.1101/2020.07.22.20160259 ◽

2020 ◽

Author(s):

Hasi Chaolu ◽

Xinri Zhang ◽

Xin Li ◽

Dongyan Li

Keyword(s):

T Cells ◽

B Cells ◽

Nk Cells ◽

Cd8 T Cells ◽

Cd4 T Cells ◽

Lymphocyte Subsets ◽

Healthy Controls ◽

Tnf Α ◽

Ifn Γ ◽

Circulating Cytokines

To investigate the immune status of people who previously had COVID-19 infections, we recruited patients 2 weeks post-recovery and analyzed circulating cytokines and lymphocyte subsets. We measured levels of total lymphocytes, CD4+ T cells, CD8+ T cells, CD19+ B cells, CD56+ NK cells, and the serum concentrations of interleukin (IL)-1, IL-4, IL-6, IL-8, IL-10, transforming growth factor beta (TGF-β), tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ) by flow cytometry. We found that in most post-recovery patients, levels of total lymphocytes (66.67%), CD3+ T cells (54.55%), CD4+ T cells (54.55%), CD8 + T cells (81.82%), CD19+ B cells (69.70%), and CD56+ NK cells(51.52%) remained lower than normal, whereas most patients showed normal levels of IL-2 (100%), IL-4 (80.88%), IL-6 (79.41%), IL-10 (98.53%), TNF-α (89.71%), IFN-γ (100%) and IL-17 (97.06%). Compared to healthy controls, 2-week post-recovery patients had significantly lower absolute numbers of total lymphocytes, CD3+ T cells, CD4+ T cells, CD8+ T cells, CD19+ B cells, and CD56+ NK cells, along with significantly higher levels of IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ and IL-17. Among post-recovery patients, T cells, particularly CD4+ T cells, were positively correlated with CD19+ B cell counts. Additionally, CD8+ T cells positively correlated with CD4+ T cells and IL-2 levels, and IL-6 positively correlated with TNF-α and IFN-γ. These correlations were not observed in healthy controls. By ROC curve analysis, post-recovery decreases in lymphocyte subsets and increases in cytokines were identified as independent predictors of rehabilitation efficacy. These findings indicate that the immune system has gradually recovered following COVID-19 infection; however, the sustained hyper-inflammatory response for more than 14 days suggests a need to continue medical observation following discharge from the hospital. Longitudinal studies of a larger cohort of recovered patients are needed to fully understand the consequences of the infection.

Download Full-text

Correction: LILRB1 Blockade Enhances Bispecific T Cell Engager Antibody–Induced Tumor Cell Killing by Effector CD8+ T Cells

The Journal of Immunology ◽

10.4049/jimmunol.1900968 ◽

2019 ◽

Vol 203 (7) ◽

pp. 2023-2024

Author(s):

Aeryon Kim ◽

Chia-Jung Han ◽

Ian Driver ◽

Aleksandra Olow ◽

Andrew K. Sewell ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Tumor Cell ◽

Cd8 T Cells ◽

Cell Killing ◽

Tumor Cell Killing ◽

Bispecific T Cell Engager

Download Full-text

Circulating immune markers predict the therapeutic effect in primary lung cancer.

Journal of Clinical Oncology ◽

10.1200/jco.2021.39.15_suppl.e21203 ◽

2021 ◽

Vol 39 (15_suppl) ◽

pp. e21203-e21203

Author(s):

Liangliang Xu ◽

Jitian Zhang ◽

Li Yang ◽

Guangqiang Shao ◽

Taiyang Liuru ◽

...

Keyword(s):

Lung Cancer ◽

T Cells ◽

B Cells ◽

Nk Cells ◽

Cd8 T Cells ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Blood Lymphocyte ◽

Lymphocyte Subpopulations ◽

Significant Difference

e21203 Background: Radiotherapy (RT), surgical resection (SR), and immunotherapy (IT) as main therapies in lung cancer have either suppressive or stimulatory effects on the immune system. It’s still unclear the mechanism involved in the systemic changes of immune cells in the blood. Peripheral blood lymphocyte subpopulations were useful markers for evaluating immune response in tumor patients. Hence, we aimed to systematically investigate the alteration of lymphocyte subpopulations during the local therapies to evaluate antitumor treatment effects. Methods: Blood samples were obtained EDTA coated tubes and then centrifuged gently for white blood cell separation. The white blood cells in 10% DMSO and 90% FBS were frozen slowly in -80°C refrigerator. The following fluorochrome-conjugated surface and nuclear antibodies were used in the lymphocyte subtyping: CD11b, CD45, CD19, CD3, CD56, CD4, CD8a, CD25,CD127 and FOXP3. The staining cells were detected in the BD FACS machine and data were analyzed by the paired T-test. The percentage of Lymphocytes, Myeloid cells, B cells, T cells, Treg, CD8+ T cells, CD4+ T cells, NK cells, and NKT were examined. Results: Between July 2019 and January 2020, a total of 176 patients eligible, including 135 RT patients and 29 SR patients,12 IT patients, with both blood collection with both Pre, During and End therapies. Before local therapies, the percentage of total T cells in the RT group was significantly higher than SR (RT v.s SR mean:64.1 v.s 55.3, P = 0.02) while CD8+ T cells (RT v.s SR mean:28.2 v.s 34.5, P = 0.04)and Tregs (RT v.s SR mean:0.0 v.s 0.1, P = 0.055) were lower. The baseline level of T cells and their subtypes showed a significant difference in these two group patients. After local therapies, myeloid cells, lymphocytes, CD4+ T cells, CD8+ T cells, NK cells were significant different. There is no significant difference due to the smaller number of IT patients. In the RT group, lymphocytes (Pre-RT v.s End-RT mean:75.2 v.s 54.3, P = 0.004) and B cells (Pre-RT v.s End-RT mean:12.6 v.s 8.0, P = 0.03) were significantly decreased while other subpopulations didn’t show any significant difference after RT. Interestingly, in the SR group, there was a significant increase in CD4+ T cells (mean:59.0 v.s 62.1, p = 0.02) a trend of reduction in CD8+ T cells (mean:34.5 v.s 32.0, p = 0.055) after SR. In addition, there was an increased trend of Tregs after IT. Conclusions: There are some different patterns of distribution in subtypes of leukocytes in operable and inoperable patients and between different therapies. All RT, SR and IT changed the distribution of peripheral blood lymphocyte subpopulations. Further validation study is warranted to validate our findings particularly in circulating lymphocytes and B cells as a marker to evaluate immune status after RT, CD4+ T cells and CD8+ T cells after SR, Tregs after IT, as well as their relationship with tumor microenvironment and implication for personalized care.

Download Full-text

Higher HHV-6 Reactivation After Cord Blood Allo-SCT Is Not Related to HHV-6 Cell Receptor CD46 Expression

Blood ◽

10.1182/blood.v120.21.1931.1931 ◽

2012 ◽

Vol 120 (21) ◽

pp. 1931-1931

Author(s):

Patrice Chevallier ◽

Nelly Robillard ◽

Marina Illiaquer ◽

Julie Esbelin ◽

Mohamad Mohty ◽

...

Keyword(s):

Stem Cells ◽

T Cells ◽

B Cells ◽

Cord Blood ◽

Nk Cells ◽

B Lymphocytes ◽

Cd8 T Cells ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Cell Receptor

Abstract Abstract 1931 Introduction: Cord Blood (CB) are increasingly used as an alternative stem cells source in adults for allogeneic Stem Cell Transplantation (allo-SCT). The risk of human herpes virus (HHV-6) reactivation is significantly higher after CB transplant vs unrelated peripheral blood stem cells (PBSC) allo-SCT (Chevallier et al, BMT 2010). Higher HHV-6 cell receptor CD46 expression on progenitor cells in CB may explain this difference (Thulke et al, Virol J 2006). Patients and Methods: We have prospectively compared the HHV-6 cell receptor CD46 expression on various cell subsets of three freshly harvested blood sources on one hand and of three graft sources on the other hand. 52 samples were used for the purpose of this study. They were issued from peripheral blood (PB, n=10), G-CSF mobilised PB (GCSF-PB, n=10), cord blood (CB, n=10), unmanipulated bone marrow (uBM, n=5), leukapheresis product (LP, n=10) and thawed CB graft (n=7). CD46 expression was assessed by FACS analysis using a FACS CANTO II (BD Biosciences, San Jose, CA, USA) on total lymphocytes, monocytes, NK cells, T and B cells subsets, plasmacytoid (pDCs) dendritic cells and stem cells. Results: As all cell subsets were found CD46 positive, CD46 mean fluorescence intensity (MFI) was then considered for comparison. When considering the three blood sources, CD46 MFI were found similar on T cells, CD4-/CD8+ and CD4-/CD8- T cells, NKT cells, Tregs, memory B lymphocytes, pDCs and CD34+ stem cells. CD46 MFI was significantly lower on CD4+/CD8- and CD4+/CD8+ T cells, transitional B cells, total and naïve B lymphocytes, and NK cells in CB while higher on monocytes. The highest CD46 MFI was observed on monocytes in CB and on CD4+/CD8+ T cells in GCSF-PB and PB. Also, highest CD46 MFI was detected on T cells compared to B lymphocytes and NK cells in all blood sources while CD46 MFI was higher on CD4+/CD8- T cells compared to CD8+/CD4- T cells. When considering the three graft sources, CD46 MFI was similar on CD4-/CD8- T cells and NKT cells. CD46 MFI was found significantly lower on all other sub-populations in thawed CB graft, except monocytes. The highest CD46 MFI was observed on monocytes in CB graft, on CD4+/CD8+ T cells in LP and on monocytes and on CD4+/CD8- T cells in uBM. Also, highest CD46 MFI was detected on T cells compared to B lymphocytes and NK cells in all graft sources while CD46 MFI was higher on CD4+/CD8- T cells compared to CD8+/CD4- T cells. Conclusion: This original study shows strong differences in term of quantitative CD46 expression between several blood and grafts samples. Our results suggest that other factors (such as another HHV-6 cell surface receptor) than the qualitative CD46 expression play a role in the higher HHV-6 reactivation observed after CB transplant in adults. Disclosures: No relevant conflicts of interest to declare.

Download Full-text