Lymphocyte Subset Counts Research Articles

Alterations of Blood Immune Cells in Elderly Patients with COVID-19 and with or without Pre-Existing Type 2 Diabetes

Elderly individuals, especially those with pre-existing conditions like type 2 diabetes mellitus (T2DM), have a high risk for developing severe cases of COVID-19. The aim of this work was to characterize the alterations of blood immune cells (BIC) in patients with symptomatic COVID-19 and confirmed SARS-CoV-2 infection, ≥60 years and who needed hospitalization in the Centro de Salud Hospital of Tucuman, Argentina, during the second peak of the pandemic in Argentina. Ten patients were enrolled from December 2020 to May 2021. Blood samples were taken at the time of admission (day 0) and five days after (day 5) for routine laboratory tests and the characterization of BIC by flow cytometry. Most of the patients were men (70%) aged between 60 and 78 years. The 70% of patients had T2DM while 50% had arterial hypertension. At day 0, all the patients had increased neutrophils and inflammatory markers (C reactive protein and D-dimers) and reduced numbers of lymphocytes, HLA-DRhi monocytes, CD16+CD56+ NK cells, CD3+HLA−DR+CD25+ cells, CD4+ and CD8+ T cells in blood. Patients received a standard treatment for COVID-19 care (O2, corticosteroids and antibiotics). The hospital treatment normalized the levels of BIC (day 5) in 30% of patients who were those with no comorbidities. In patients with T2DM, BIC recovery was variable. In T2DM patients who required administration of plasma (30%), prolonged O2 therapy (40%) or referral to the intensive care unit (10%) significant reductions of CD16+CD56+, CD3+HLA−DR+CD25+, CD4+ and CD8+ cells were observed between days 0 and 5. In line with previous studies, our results show that absolute counts of major lymphocyte subsets in blood are significantly and substantially decreased during the course of severe COVID-19 disease in elderly patients. These BIC alterations may persist despite clinical care in elderly patients with T2DM. Further studies are needed to investigate the utility of early lymphocyte subset measurements as prognostic biomarkers of disease severity, mortality, and response to treatment in COVID-19 elderly patients with T2DM.

Decreased Immune Response in Alexithymic Women: A One-Year Longitudinal Study

Although previous cross-sectional studies suggested significantly dysregulated immune response in alexithymia, there is a lack of longitudinal studies. We sought to determine the reliability of the reported relationship between alexithymia and decreased immune response in a longitudinal study. Thirty-eight healthy women who had participated in a cross-sectional study were recontacted 1-year later. Of this sample, 26 were finally included: 13 females who had been found to be alexithymic, and 13 females who were classified as non-alexithymic under the 20-item Toronto Alexithymia Scale during the first phase of the study. A year later, they were still healthy women without any psychiatric disorders, their ages now ranging from 19 to 28 years old. Lymphocyte subset counts (CD4, CD8), in vitro production of interleukin 1β (IL-1β), IL-2, IL-4, and IL-10 by phytohemagglutinin stimulated peripheral blood lymphocytes, as well as serum cortisol levels, were compared between women with and without alexithymia. One-year later, alexithymic women still had significantly lowered in vitro production of IL-2 and IL-4, with lowered IL-2/IL-10 ratio and a reduced percentage of CD4. This is the first ever published study assessing cytokine production during a follow-up of alexithymics. Although our results should be interpreted with caution due the small sample size, they suggest a sustained reduction in both major type 1 and type 2 cytokines while the former seems to be more affected. The potential long-term health impact, if any, is still to be determined.

Low IgG trough and lymphocyte subset counts are associated with hospitalization for COVID-19 in patients with primary antibody deficiency

Low IgG trough and lymphocyte subset counts are associated with hospitalization for COVID-19 in patients with primary antibody deficiency

A systematic review and meta-analysis on the association between lymphocyte subsets and the severity of COVID-19

Introduction: Prominent prognostic parameters that reflect the severity of coronavirus disease 2019 (COVID-19) to adopt an appropriate therapeutic approach are not fully identified. This systematic review and meta-analysis aimed to explore the association between lymphocyte variation and disease severity in COVID-19 individuals. Methods: We searched Web of Science, Scopus, PubMed, EMBASE and WHO website to retrieve studies investigating lymphocyte subset counts in non-severe and severe cases of COVID-19. The pooled standardized mean difference (SMD) between two groups and the pooled average count of each lymphocyte subset were assessed by employing a random-effect model. Results: Thirty-nine investigations on 5087 participants, including 3578 non-severe patients and 1509 severe patients, were included. The pooled analysis showed that non-severe patients had higher total T lymphocytes (SMD = 1.01; 95% CI: 0.82, 1.20; I2 = 75.7%), T helper cells (SMD = 1.07; 95% CI: 0.85, 1.28; I2 = 85.4%), T cytotoxic cells (SMD = 1.07; 95% CI: 0.82, 1.32; I2 = 87.1%), B cells (SMD = 0.72; 95% CI: 0.45, 0.98; I2 = 79.7%), and natural killer cells (SMD = 0.65; 95% CI: 0.47, 0.84; I2 = 63.1%) than severe patients and the average count of the corresponding lymphocyte signatures in non-severe patients/severe patients were 878.88/448.40, 493.12/268.96, 311.91/158.91, 177.09/110.37, and 155.02/103.09 cells/μL, respectively. Conclusion: Lymphopenia may be a dilemma in COVID-19 management because over-activation of lymphocytes may lead to cytokine storm or acute respiratory distress syndrome (ARDS). In contrast, lymphopenia may increase SARS-CoV-2 amplification and COVID-19 severity. Therefore, novel therapies targeting lymphocyte proliferation or contraction may counterbalance lymphocyte counts in these patients.

BMSCs Regulate the Function of NK Cell By CD155/Tigit/CD226 Pathway in MDS Patients

Objective To analyze the immune status of MDS patients and evaluate its impact on prognosis.To investigate the specific mechanism of how mesenchymal stromal cells (MSCs) affecting immunity.Methods The study included 84 healthy controls and 84 inpatients with primary MDS, 22 patients with AML who were initially diagnosed in the Department of Hematology, General Hospital of Tianjin Medical University from January 2017 to July 2021.We collected flow cytometry(FCM) reports and clinical data. All MDS patients were stratified by IPSS-R for disease risk. According to IPSS-R classification, Very Low/Low and Int/High/Very high were divided into lower-risk MDS group and higher-risk MDS group, respectively.1. Statistical analysis of lymphocyte subset counts and cytokines in peripheral blood of different types of patients and healthy controls. 2. Correlation analysis between hemoglobin , platelets,neutrophil, blast cells, cytogenetics and lymphocyte counts was performed.3.We generated MSCs in BM samples from MDS patients and HCs.The expression of CD155 in MSCs and TIGIT/CD226 in lymphocytes were detected by FCM.Results 1.Percentage counts of NK cells in the HC group(19.94,95%CI 17.86-22.02，P<0.001)were significantly higher than other groups.The higher-risk group of MDS(11.51,95%CI 9.34-13.68) was obviously lower than the lower-risk group(16.91,95%CI 13.85-19,97)(P=0.006),close to the AML group(9.77,95%CI 6.33-13.20,Figure1).Meanwhile, the level of IFN-Ƴ in serum which is secreted mainly by NK cells was also the highest in the HC group(5.50,95%CI 3.74-7.26), followed by the MDS group and the lowest in the AML group(2.64,95%CI 1.91-3.37,Figure1).In addition, CD8+ T cells and CD19+ cells had similar results as NK cells, but there was no significant difference with CD3+ cells and CD4+ T cells.2.Significantly higher level of NK cells percentage counts were found in patients with hemoglobin ≥ 100 ×10 12/L compared to patients with lower hemoglobin(23.23,95%CI 17.26-29.21 and 15.77,95%CI 13.00-18.55,P=0.010). While the levels of NK cells were higher in patients with blast cells≤5% than in those with higher blast cells.(19.51,95%CI 16.09-22.93 and 14.65,95%CI 11.55-17.74,P=0.027). No significant difference was found between NK cell levels with regard to platelet and neutrophil counts.CD8+ T cells behaved similarly to NK cells. 3.The expression of CD155 on the surface of BMSCs was significantly higher in the MDS group than that in the HC group(P=0.001，Figure3).Moreover,MDS patients had higher expression of TIGIT(P=0.012) and lower expression of CD226(P=0.001,Figure4B) on the surface of NK cells in bone marrow than that in HCs.And CD8+ T cells also have similar results as NK cells.We analyzed the correlation between TIGIT of NK cells and CD155 of BMSCs, and found that they were negatively correlated（P=0.0297）, while CD226 was positively correlated with CD155（P=0.0706，Figure 4C）.Conclusions The decreased immune function in MDS patients is associated with prognosis.BMSCs are responsible for inducing an immune-suppressive microenvironment in MDS through CD155/TIGIT/CD226 pathway, the underlying mechanism remains to be further study. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

A novel ITGA3 homozygous splice mutation in an ILNEB syndrome child with slow progression

Background and aimsILNEB (interstitial lung disease, nephrotic syndrome, epidermolysis bullosa) syndrome is caused by ITGA3 mutations. Demises usually happened at infancy. This study reports a complete ILNEB syndrome child with slow disease progression. Materials and methodsClinical data and related specimens were collected. Genomic DNA was extracted for genetic sequencing. Integrin α3 expression was detected by western blotting and immunofluorescence staining. ResultsThe patient was male. He experienced recurrent rashes shortly after birth. His sparse eyebrows and eyelashes gradually lost. The patient was vulnerable to respiratory infections and had recurrent fever after vaccine immunization after 4 years. He was found with nephrotic syndrome and polycystic renal dysplasia at 8 years and progressed to end-stage renal disease at 12 years. A chest Computed Tomography revealed intestinal lung disease at 8 years. Continuous oxygen supplementation was needed at 13 years. Counts of lymphocyte subsets revealed elevated percentage of double-negative T cells and activated T cells. Next-generation sequencing revealed a novel homozygous splice mutation c.2219 + 4A > Cin ITGA3 that was predicted to be deleterious. The mutation resulted in exon17 skipping with the loss of 80 bp in the mRNA. The aberrant integrin α3 mRNA level was lower compared to the healthy control. Integrin α3 protein was not detected in urine epithelial cells and skin of the patient. ConclusionsWe report a patient harboring a novel ITGA3 homozygous splice mutation who presented with complete ILNEB syndrome but slow disease progression. Immune disorders were suspected.

Peripheral Lymphocyte Subsets Absolute Counts as Feasible Clinical Markers for Predicting Surgical Outcome in Gastric Cancer Patients After Laparoscopic D2 Gastrectomy: A Prospective Cohort Study.

BackgroundImmune function influenced patients’ recovery from major abdominal surgery. The aim of this study is to explore the clinical feasibility of peripheral lymphocyte absolute counts for predicting short-term surgical outcomes in gastric cancer patients after laparoscopic D2 gastrectomy.MethodsThis is a prospective cohort study from a single tertiary referral hospital. Patients diagnosed with gastric cancer who met the inclusion criteria were included in this study. We collected the demographic and clinicopathological characteristics of included patients. We monitored perioperative dynamics of absolute counts of peripheral lymphocyte subsets. Predictive factors for length of postoperative hospital stay and complications were investigated in univariate and multivariate analyses.ResultsA total of 137 gastric cancer patients were included. Decreased preoperative absolute counts of peripheral lymphocyte subsets were correlated with advanced clinical stage. In multivariate analysis, independent predictive factors for prolonged hospital stay were age (p=0.04), decreased preoperative B cell counts (p=0.05), decreased preoperative NK cell counts (p=0.05) and complications (p<0.01). For postoperative complication, independent predictive factors were age (p=0.02), operation time (p=0.05), lymphocyte to C-reactive protein ratio (p=0.01) and decreased preoperative B cell counts (p=0.01).ConclusionOur findings for the first time revealed that absolute counts of peripheral lymphocyte subsets are independent predictive factors for surgical outcomes in gastric cancer patients after D2 gastrectomy. We suggested that patients with impaired immune state should receive both preoperative immune modulator and nutritional support.

An association between immune status and chest CT scores in COVID-19 patients.

BackgroundThe characteristic features of the immune responses of COVID‐19 patients and how they reflect lung involvement have not been clearly elucidated.AimThe aim of this study was to examine the immune status and the correlations thereof with chest CT scores and lung involvement of patients with COVID‐19.MethodsIn this retrospective and single‐center study, 72 patients with laboratory‐confirmed COVID‐19 were recruited. The counts of peripheral lymphocyte subsets (CD3+ T cells, CD4+ T cells, CD8+ T cells, CD19+ B cells and CD16+ 56+ NK cells) and those of serum immunoglobulins (IgA, IgG, IgM) were measured and their associations with chest CT scores analysed.ResultsThe proportions of lymphopenia in patients with extensive lung involvement were twice that in the general study population. In the severe disease group, the levels of total lymphocytes, T cells, B cells, NK cells; and serum IgA levels, were significantly lower than in the mild disease group (all P < .05). We found that the numbers of lymphocyte subsets and the IgA level negatively correlated with the chest CT scores. On multivariate regression analysis, pretreatment decreases in total lymphocytes, CD3+ T cells, CD4+ T cells, and CD19+ B cells, and serum IgA levels, were independent predictors of severe lung involvement.ConclusionsThe cell numbers of peripheral lymphocyte subsets and the serum IgA level were negatively correlated with the chest CT scores in COVID‐19 patients. These parameters tended to independently predict severe lung involvement in such patients.

Reference values for T and B lymphocyte subpopulations in Turkish children and adults

Background/aim Established reference values are critical for the interpretation of immunologic assessments. In particular, the proportion and absolute counts of T- and B- cell subpopulations are subject to change with age and ethnicity. We aimed to establish age-specific reference values for lymphocyte subsets using updated immunophenotyping panels.Materials and methods We studied a total of 297 healthy Turkish subjects aged 0 to 50 years, stratified into major age brackets in a cluster factor of 10 per age-group. The predetermined age intervals contained randomly allocated participants enrolled over a period of 6 months, who were homogenously distributed by sex. We analyzed a complete blood count test and simultaneously with detailed immunophenotyping enumerated the percent and absolute cell counts of lymphocyte subsets. Results The percentage and absolute counts of lymphocyte subsets show a marked surge across the age-span. T helper, T cytotoxic, and the natural killer cell numbers were increasing from birth until 6 months, followed by a gradual decrease thereafter. B cell numbers were rising until 2 years, followed by a gradual decrease for the upcoming years, accompanied by a steady expansion of unclass-switched- and class-switched- B cells.Conclusion We provide updated extensive reference intervals for lymphocyte subpopulations in Turkish people.

Characteristics of Peripheral Lymphocyte Subsets in Patients With Acute-On-Chronic Liver Failure Associated With Hepatitis B.

Background and Aims: Acute-on-chronic liver failure (ACLF) is a rare, but dramatic clinical syndrome. There is substantial evidence suggesting that immunity-mediated inflammation plays an important role in HBV-ACLF. Our aim was to characterize the proportion and cell counts of peripheral blood lymphocyte subsets in acute-on-chronic liver failure patients caused by HBV infection.Methods: One hundred and seventeen patients were enrolled in this study, including those with HBV-related ACLF (HBV-ACLF; n = 70), and HBV related non-ACLF patients (HBV non-ACLF; n = 47). Demographics, clinical and laboratory data at hospital admission were retrospectively analyzed. The percentage and cell count of peripheral lymphocyte subsets were evaluated by flow cytometry. Comparison analysis was performed by t-test or non-parametric Mann–Whitney U-test. Actuarial probabilities of death were calculated by the Kaplan-Meier method.Results: Both circulating lymphocyte count and lymphocyte percentage were significantly reduced in patients with HBV-ACLF (P < 0.001). The CD8+ T cell, CD4+ T cell, and CD16+CD56+ NK cell counts were significantly decreased in HBV-ACLF. Consistently, flow cytometric analysis showed that CD8+ T cell counts were significantly decreased in non-survivors, while no significant differences were found in CD4+ T cell, CD19+ B cell, or CD56+CD16+ NK cell counts. Furthermore, the group with the lower CD8+ T cell count displayed a significantly higher mortality rate compared with the group with the higher CD8+ T cell count.Conclusions: The abnormal prevalence of lymphocyte subsets may be important in the pathogenesis of HBV-ACLF. The decrease in CD8+ T cell counts may be related to poor survival in HBV-ACLF patients.

Immune cell profiling and antibody responses in patients with COVID-19

BackgroundAlthough there are a growing number of studies on evaluating lymphocyte subset counts as prognostic factors for COVID-19 disease severity, the lymphocyte subsets’ analyses of both IgM and IgG responders and non-responders during the periods after onset of symptoms, have not been conducted yet. So, this study aimed to evaluate immune cell profiling of COVID-19 patients with and without antibody responses.MethodsIn this cross-sectional study, the levels of peripheral lymphocyte subsets were measured using flow cytometry in 53 patients with positive SARS-CoV-2 RT-PCR, for whom antibody testing of COVID-19 was performed.ResultsThe white blood cell, neutrophil, and lymphocyte counts consistently decreased in the IgM and IgG non-responder group, while the differences in the median value between the two study groups were found to be statistically significant only in terms of neutrophil counts (P = 0.024 for IgM response and p-value = 0.046 for IgG response, respectively). Moreover, the level of neutrophil-to-lymphocyte ratio was observed to be significantly lower in the IgM or IgG non-responder group compared to the IgM or IgG responder group (3.6 ± 3.1 vs. 6.3 ± 4.2; p-value = 0.021). The patients with IgM antibody response had a significantly lower CD20+ lymphocytes (11% versus 15% in the groups without IgM antibody response, p-value = 0.031), The percentages of NK cells and CD4+ T cells significantly increased in the patients with IgG antibody response compared to those without IgG antibody response (13% versus 10%, p-value = 0.028, and 41.5% versus 34%; p-value = 0.03, respectively). Moreover, the patients who produced IgM or IgG antibody had significantly higher percentages of total T lymphocytes (64% versus 54%; p-value = 0.017), CD4+ T cells (41% versus 34%; p-value = 0.038), and NK cells (13% versus 9%, p-value = 0.023) compared to the group with no serological response. No significant difference was observed in the percentage of other lymphocyte subsets, including CD8+ T cells, Treg cells, and CD19+ B cells.ConclusionOur results suggest that the total T cells, CD4+ T cells, and NK cells percentages are linked to serological response. Moreover, our findings suggested that neutrophil absolute counts and neutrophil-to-lymphocyte ratio may be valuable predictors of IgM or IgG antibody response.

Immune Reconstitution after Allogeneic Stem Cell Transplantation - a Systematic Single Center Survey

The renewal of the immune system after allogeneic hematopoietic stem cell transplantation (HSCT) is a complex process not fully understood. Recently, the use of reduced intensity conditioning (RIC) regimens, new anti-viral drugs and intensified GvHD treatment changed the landscape of allogeneic transplantation. Here, the influence of several parameters on the development of the cellular and humoral immunity of 136 patients consecutively transplanted in a single center was analyzed.All adult patients transplanted during a period of three years (September 2010 to August 2013), were analyzed in respect of immunoglobulin levels with the turbidimetric method, serum electrophoresis, immunofixation and lymphocyte subset counts by flow cytometry. Also the occurrence of a monoclonal/biclonal gammopathy was reported. In addition, we looked for donor chimerism, B and T cell receptor repertoire of peripheral blood samples. Most patients received a reduced conditioning regimen; nearly all patients received either anti-thymoglobulin (ATG) or alemtuzumab (25/136 matched related donors) leading to a relatively low rate of chronic GvHD (40%). The immune parameters obtained one year after stem cell transplantation were correlated with relevant factors of stem cell transplantation, namely the conditioning regimen, diagnosis, relapse rate, age, sex and history of CMV infection, acute and chronic GvHD using Pearson correlation, t-test and regression analysis (SPSS).A normal CD4/CD8 ratio at day 360 after HSCT was only seen in 14% of evaluable patients, while it was reduced in 83%. This was mainly due by an impaired CD4 cell count while the CD8 cell count was even increased in 42%. The CD8 cell count was significantly higher in patients after CMV infection (p<0.001) and in those not receiving alemtuzumab as part of the conditioning regimen (p=0.003). The IgG level was normal in 51%, reduced in 31% and increased in 17 % of tested patients. The IgG level correlated with a history of CMV infection, NK, CD4, and CD8 cell count (all p≤0.025); but age, sex, diagnosis, relapse, use of RIC, acute and chronic GvHD had no significant impact. The development of a new clonal gammopathy was found in 18 patients after undergoing a HSCT and was in nearly all cases reversible. Interestingly, this was associated with chronic GvHD (p=0.034), but not any of the other parameters.Almost all patients show a compromised immune system one year after allogeneic stem cell transplantation mainly characterized by an inverted CD4/CD8 ratio. Whether an increased CD8 cell count may not only reflect the response to viral infections but in some cases improved immunosurveillance, is hard to document. Interestingly, the immunoglobulin levels are highly variable ranging from antibody deficiency to hypergammaglobulinemia positively correlating with CMV reactivation. Continuous disbalanced immunoreactivity indicated by clonal gammopathy was associated with chronic GvHD. The systematic evaluation of these basic immune parameters may lead to better therapeutic guidance in patients after allogeneic HSCT. DisclosuresNo relevant conflicts of interest to declare.

Impact of age and gender on lymphocyte subset counts in patients with COVID-19.

In symptomatic patients with acute Coronavirus disease 2019 (COVID‐19), lymphocytopenia is one of the most prominent laboratory findings. However, to date age and gender have not been considered in assessment of COVID‐19‐related cell count alterations. In this study, the impact of COVID‐19 as well as age and gender on a large variety of lymphocyte subsets was analyzed in 33 COVID‐19 patients and compared with cell counts in 50 healthy humans. We confirm that cell counts of total lymphocytes, B, NK, cytotoxic and helper T cells are reduced in patients with severe COVID‐19, and this tendency was observed in patients with moderate COVID‐19. Decreased cell counts were also found in all subsets of these cell types, except for CD4+ and CD8+ effector memory RA+ (EMRA) and terminal effector CD8+ cells. In multivariate analysis however, we show that in addition to COVID‐19, there is an age‐dependent reduction of total, central memory (CM), and early CD8+ cell subsets, as well as naïve, CM, and regulatory CD4+ cell subsets. Remarkably, reduced naïve CD8+ cell counts could be attributed to age alone, and not to COVID‐19. By contrast, decreases in other subsets could be largely attributed to COVID‐19, and only partly to age. In addition to COVID‐19, male gender was a major factor influencing lower counts of CD3+ and CD4+ lymphocyte numbers. Our study confirms that cell counts of lymphocytes and their subsets are reduced in patients with COVID‐19, but that age and gender must be considered when interpreting the altered cell counts.

Baseline T-lymphocyte subset absolute counts can predict both outcome and severity in SARS-CoV-2 infected patients: a single center study

The aim of this study was to evaluate the role of baseline lymphocyte subset counts in predicting the outcome and severity of COVID-19 patients. Hospitalized patients confirmed to be infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) were included and classified according to in-hospital mortality (survivors/nonsurvivors) and the maximal oxygen support/ventilation supply required (nonsevere/severe). Demographics, clinical and laboratory data, and peripheral blood lymphocyte subsets were retrospectively analyzed. Overall, 160 patients were retrospectively included in the study. T-lymphocyte subset (total CD3+, CD3+ CD4+, CD3+ CD8+, CD3+ CD4+ CD8+ double positive [DP] and CD3+ CD4− CD8− double negative [DN]) absolute counts were decreased in nonsurvivors and in patients with severe disease compared to survivors and nonsevere patients (p < 0.001). Multivariable logistic regression analysis showed that absolute counts of CD3+ T-lymphocytes < 524 cells/µl, CD3+ CD4+ < 369 cells/µl, and the number of T-lymphocyte subsets below the cutoff (T-lymphocyte subset index [TLSI]) were independent predictors of in-hospital mortality. Baseline T-lymphocyte subset counts and TLSI were also predictive of disease severity (CD3+ < 733 cells/µl; CD3+ CD4+ < 426 cells/µl; CD3+ CD8+ < 262 cells/µl; CD3+ DP < 4.5 cells/µl; CD3+ DN < 18.5 cells/µl). The evaluation of peripheral T-lymphocyte absolute counts in the early stages of COVID-19 might represent a useful tool for identifying patients at increased risk of unfavorable outcomes.

Dynamic changes in peripheral blood lymphocyte subset counts and functions in patients with diffuse large B cell lymphoma during chemotherapy

BackgroundThis study aimed to analyze the lymphocyte subsets, their activities and their dynamic changes during immunochemotherapy in patients newly diagnosed with diffuse large B cell lymphoma (DLBCL).MethodsPatients with DLBCL (n = 33) were included in the present study. Their peripheral lymphocyte subsets, phenotypes and functions were detected using flow cytometry. The dynamic results of lymphocyte activities were available for 18 patients.ResultsCompared with healthy controls (HCs), the counts of CD3+, CD4+, and CD8+ T cells as well as those NK cells decreased in patients newly diagnosed with DLBCL, mainly attributed to patients with high risk of prognosis assessed by International Prognostic Index (IPI) score. Lymphocyte counts didn’t present significant difference between high risk (IPI scores 3–5) and low risk patients (IPI scores 0–2), but CD4+ T cells and CD8+ T cells expressed higher levels of CD28 and HLA-DR, respectively, in patients with IPI score ranging from 3 to 5. Patients at high risk harbored higher percentage of regulatory T cells (Tregs), and their CD4+ and CD8+ T cells produced lower levels of IFN-γ, reflecting an impaired cellular immune response. The dynamic changes of lymphocyte numbers and functions during treatment were further investigated. Total counts of CD3+, CD4+, CD8+ T and NK cells progressively decreased because of the cytotoxicity of chemotherapy and then gradually recovered after six cycles treatment (rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisone, R-CHOP). The functions of CD4+ and CD8+ T cells recovered by the end of two cycles R-CHOP treatment, although NK cell function was not significantly affected throughout treatment. These results suggest that the counts and functions of lymphocytes are significantly decreased in patients with DLBCL, particularly those of CD4+ and CD8+ T cells.ConclusionsThe absolute counts and functions of CD4+, CD8+ T cells, which were significantly lower in patients with DLBCL, gradually recovered after effective treatment. Therefore, combined detection of T cell counts and functions are critically important for administering effective personalized immunotherapy as well as for identifying new prognostic markers or DLBCL.

652 Association Between Poor Sleep and Lymphocyte Subsets In Chronic HIV Infection

Abstract Introduction Low CD4+ T lymphocyte counts and CD4+/CD8+ lymphocyte ratios predict mortality and cardiovascular risk among people living with HIV (PLWH). Whether polysomnographic (PSG) sleep measures impact T lymphocyte subset counts among PLWH is unknown. We sought to evaluate the association between lymphocyte subsets and PSG-derived sleep measures in a cohort with HIV seropositive men. Methods We analyzed data from HIV seropositive men who have sex with men participating in the Multicenter AIDS Cohort Study on antiretroviral therapy for &amp;gt;1 year with undetectable (&amp;lt;500 copies/mL) plasma HIV-1 RNA who underwent a sleep evaluation with home polysomnography. The following seven sleep parameters were examined: total sleep time (TST), sleep efficiency, sleep stage (N1, N2, N3, and REM) duration, and apnea-hypopnea index. Multivariable linear regression models adjusted for age and body mass index were used to assess whether sleep measures were associated with CD4+ T cell count, CD8+ T cell count, or CD4+/CD8+ ratio. Results Participants (n= 286) had a mean age of 55.2 ± 11.3 years, 52.8% had sleep apnea and mean CD4+ count was 728 ± 306 cells/mm3. None of the sleep measures were associated with CD4+ counts but longer TST and REM duration were associated with lower CD8+ counts and higher CD4+/CD8+ ratio. In adjusted analyses, every one hour increase in TST was associated with a 35 ± 18 cells/mm3 lower CD8+ count (p=0.049) and 6.3% elevation in CD4+/CD8+ ratio (p=0.006) while every hour increase in REM was associated with 123 ± 50 cells/mm3 lower CD8+ count (p=0.01) and 20% elevation in CD4+/CD8+ ratio (p=0.003). Conclusion In PLWH, longer total sleep time and REM sleep duration are associated with protective CD4+/CD8+ ratios due to lower CD8+ cell count. Further research is needed to assess if longer sleep duration is associated with decreased inflammatory markers. Support (if any) American Thoracic Society Academic Sleep Pulmonary Integrated Research/Clinical (ASPIRE) Fellowship

Issue Highlights — May 2021

Issue Highlights — May 2021

Early immune responses and prognostic factors in children with COVID-19: a single-center retrospective analysis

BackgroundEarly diagnostic indicators and the identification of possible progression to severe or critical COVID-19 in children are unknown. To investigate the immune characteristics of early SARS-CoV-2 infection in children and possible key prognostic factors for early identification of critical COVID-19, a retrospective study including 121 children with COVID-19 was conducted. Peripheral blood lymphocyte subset counts, T cell-derived cytokine concentrations, inflammatory factor concentrations, and routine blood counts were analyzed statistically at the initial presentation.ResultsThe T lymphocyte subset and natural killer cell counts decreased with increasing disease severity. Group III (critical cases) had a higher Th/Tc ratio than groups I and II (common and severe cases); group I had a higher B cell count than groups II and III. IL-6, IL-10, IFN-γ, SAA, and procalcitonin levels increased with increasing disease severity. Hemoglobin concentration, and RBC and eosinophil counts decreased with increasing disease severity. Groups II and III had significantly lower lymphocyte counts than group I. T, Th, Tc, IL-6, IL-10, RBC, and hemoglobin had relatively high contribution and area under the curve values.ConclusionsDecreased T, Th, Tc, RBC, hemoglobin and increased IL-6 and IL-10 in early SARS-CoV-2 infection in children are valuable indices for early diagnosis of severe disease. The significantly reduced Th and Tc cells and significantly increased IL-6, IL-10, ferritin, procalcitonin, and SAA at this stage in children with critical COVID-19 may be closely associated with the systemic cytokine storm caused by immune dysregulation.

Immunopathological reactions, endothelial dysfunction and pathological angiogenesis as independent mechanisms of maladaptive left ventricular remodeling in ischemic and nonischemic heart failure patients

Regardless of the great progress in studying the heart failure (HF) pathophysiology, the question about involvement of immune cells activation, systemic inflammation, inflammatory cytokine dysregulation and endothelial dysfunction in maladaptive left ventricular (LV) remodeling in ischemic and nonischemic HF patients is still open to discussion. The aim was to study the characteristics of immunopathological reactions (immunoinflammatory and autoimmune), endothelial dysfunction and pathologic angiogenesis in maladaptive LV remodeling in ischemic and nonischemic HF patients. Materials and methods. A total of 20 healthy volunteers, 31 ischemic HF patients (group 1) and 43 nonischemic HF patients (group 2) were enrolled in the study. All the patients underwent coronarography, ventriculography, echocardigraphic examination. The main lymphocyte subset counts (flow cytometry), serum concentration of C-reactive protein (CRP), vascular endothelial growth factor A (VEGF), TNFα, endothelin-1 (enzyme-linked immunosorbent assay (ELISA)), autoantibodies to myocardium and vessels were detected. Results. Regardless of the HF etiology, all the examined patients demonstrated echocardiographic features of maladaptive LV remodeling and severe intracardiac hemodynamic disorders that was associated with immune system activation, namely increased total and subset lymphocyte counts, chronic systemic inflammation (CRP), autoimmune process with an increase in autoantibodies to myocardium and vessels, and endothelial dysfunction (increased endothelin-1 and VEGF). Under-expression of TNF-α combined with over-expression of VEGF seemed to indicate pathological angiogenesis in ischemic and nonischemic HF patients Conclusions. Significantly increased VEGF levels in heart failure patients can be considered as additional integral key marker of immune inflammation, endothelial dysfunction and pathological angiogenesis and may indicate maladaptive cardiac remodeling in severe heart failure.

Establishment of CD4 and CD8 Lymphocyte subsets in a healthy HIV and Toxoplasma seronegative pregnant women in Libya

Most of the diagnostic laboratories in Libya often depend on western textbooks for CD4+- and CD8+ T-lymphocyte reference values. In this paper, we established reference ranges for the Libyan Toxoplasma, HIV, HBV, and HCV seronegative healthy pregnant women in all trimesters of pregnancy, and compared them with a control group of non-pregnant women. Wholeblood samples were collected to provide normal ranges for CD4+ and CD8+ Lymphocyte subsets expressed as mean ± standard division. A total of 110 Libyan women who came from Tripoli and Zwara districts were investigated; 70 pregnant women (aged 27.8 ± 2.99, range 18-40 years old) and 40 non-pregnant women (aged 22.7±3.01, range 18-40 years old) were included as controls. All cases/controls were seronegative for toxoplasmosis, HIV, HBV and HCV. The CD4+ cell counts were 685±256 cell/#l at the first trimester (T1), 740±202 at T2, and 923±203 cell/#l at T3. While the CD8+ cell counts were 451±171 cell/#l at T1, 541±168 at T2, and 753±190 cell/#l at T3. The CD4:CD8 ratios were 1.5±0.64 at T1, 1.4±0.51 at T2, and 1.2±0.36 at T3. Moreover, the mean absolute CD4+ and CD8+ counts for the control group were 1001±232 cell/#l and 717±159 cell/#l respectively. Absolute counts of CD4+ and CD8+ cells in pregnant women were significantly lower as compared to controls (P&lt;0.05). Statistically significant decrease in the CD4+ and CD8+ cell counts was reported during T1 (P&lt;0.05). These values increased significantly during the T2, and was comparable to the controls during T3 (P&gt;0.05). The absolute CD4+ and CD8+ cell counts decreased with age for both groups. Geographical variation was reported for the cell counts between Tripoli and Zwara district at T3. We established reference ranges of CD4+ and CD8+ T-lymphocytes for the Libyan healthy pregnant women and discussed their use as prognostic markers. Further cohorts with greater sample size may be required to define the stage of the disease in relation to the normal CD4+ and CD8+ T lymphocyte count subsets in the Libyan population.