scholarly journals New Insights into Blood Circulating Lymphocytes in Human Pneumocystis Pneumonia

2021 ◽  
Vol 7 (8) ◽  
pp. 652
Author(s):  
Eléna Charpentier ◽  
Catherine Marques ◽  
Sandie Ménard ◽  
Pamela Chauvin ◽  
Emilie Guemas ◽  
...  
Keyword(s):  
Nk Cells ◽  
Pneumocystis Pneumonia ◽  
Health Care Facilities ◽  
Lymphocyte Subpopulations ◽  
Central Memory ◽  
Th2 Response ◽  
Risk Of Mortality ◽  
Circulating Lymphocytes ◽  
Immunosuppressed Patients ◽  
Lymphocyte Populations

The host lymphocyte response is decisive in Pneumocystis pneumonia (PCP) pathophysiology but little is known of the specific roles of lymphocyte subpopulations in this fungal infection. Peripheral NK, NKT, B, TCD4+ and TCD8+ subpopulations were compared by immunophenotyping between 20 patients diagnosed with PCP (PCP(+)] and 20 uninfected immunosuppressed patients (PCP(−)). Among PCP(+) subjects, the lymphocyte populations were also compared between surviving and deceased patients. Low B cell count (<40 cells/µL) was more frequent in PCP(+) than in PCP(−) patients (p = 0.03), while there was no difference for the TCD4 count. Among the PCP(+) group, the 7 deceased patients had lower Th1 (p = 0.02) and Tc1 (p = 0.03) populations, higher Th2 response (p = 0.03), higher effector TCD8 (p < 0.01), lower central memory TCD8 (p = 0.04) and reduced NK cells (p = 0.02) compared with the 13 survivors. Th1/Th2 ratio < 17, CD8 Tc1 < 44%, effector TCD8 < 25%, central memory TCD8 < 4%, NK cells < 50 cells/µL and total lymphocytes < 0.75 G/L were associated with a higher risk of mortality (p = 0.003, p = 0.007, p = 0.0007, p = 0.004, p = 0.02 and p = 0.019, respectively). The traditional analysis of TCD4 and TCD8 populations may be insufficient in the context of PCP. It could be completed by using B cells to predict the risk of PCP, and by using lymphocyte subpopulations or total lymphocyte count, which are easy to obtain in all health care facilities, to evaluate PCP prognosis.

scholarly journals Innate immune protein Tag7 stimulates the appearance of cytotoxic NK cells after incubation with lymphocytes

2019 ◽  
Vol 484 (6) ◽  
pp. 777-780
Author(s):  
T. N. Sharapova ◽  
E. A. Romanova ◽  
L. P. Sashchenko ◽  
N. V. Gnuchev ◽  
D. V. Yashin
Keyword(s):  
Tumor Cell ◽  
Nk Cells ◽  
Cell Lines ◽  
Lymphocyte Subpopulations ◽  
Innate Immune ◽  
Tumor Cell Lines ◽  
Cytotoxic Lymphocyte

Tag7 (PGRP-S) is an innate immune protein that is involved in the antibacterial and antitumor defense and stimulates the maturation of cytotoxic lymphocyte subpopulations. It was found that the incubation of lymphocytes with Tag7 for 3 days promotes the appearance of cytotoxic NK cells that are active against a number of tumor cell lines.

scholarly journals P423 NF-kB as a prognostic marker of response to biologic therapy in children with IBD

2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S386-S387
Author(s):  
T Radigina ◽  
A Illarionov ◽  
D Kuptsova ◽  
A Potapov ◽  
S Petrichuk ◽  
...  
Keyword(s):  
Nk Cells ◽  
Statistical Evaluation ◽  
Biologic Therapy ◽  
Positive Outcome ◽  
Healthy Children ◽  
Innate And Adaptive Immunity ◽  
Tnf Blockers ◽  
Patient Status ◽  
Endoscopic Remission ◽  
Lymphocyte Populations

Abstract Background The transcription factor NF-kB is a regulator of innate and adaptive immunity through the activation of various pro and anti-inflammatory mediators. The aim of this study was to assess the prognostic value of changes in the level of NF-kB translocation in lymphocyte populations in response to infusion of TNF blockers in children with IBD. Methods There were examined 44 children with IBD (27-CD, 17-UC) and 20 conditionally healthy children aged 3–18 years. Patient status (exacerbation, remission) was assessed by the PUCAI (UC) and PCDIA (CD) indices. There were determined the percentage of cells with NF-kB translocation in populations CD3+CD4+ (Th), CD3+CD8+(Tc), CD3-CD19+ (B cells), CD3-CD16 / 56+(NK cells), CD3+CD4+CD161+ (Th17), CD3+CD4+CD25highCD127low (Tregs) with NF-kB translocation kit using flow cytometry ImageStreamX MKII (Amnis) before infusion of TNF blockers (infliximab, adalimumab), one day after infusion and after 6 months therapy. Statistical evaluation was performed using a nonparametric Mann–Whitney test. The results are presented as the median per cent of cells with NF-kB translocation (Me [Q 0.25-Q 0.75]). Results It was observed an increased level of NF-kB translocation in B-lymphocytes (Me 64 [53–81] – Me 38 [33–45]; p = 6 × 10−5), NK cells (Me 40 [33 -55] – Me 21 [18–26]; p = 4x10-4), Tc (Me 20 [15–24] – Me 16 [13–17]; p = 0.03), Th17 (Me 23 [21–28] – Me 18 [16–19]; p = 0.005) in children with exacerbation compared with remission. The level of NF-kB translocation in populations of lymphocytes during the period of clinical endoscopic remission did not differ from conditionally healthy children. The correlation between the level of NF-kB translocation and the number of cells in the studied lymphocyte populations was not found. In children with IBD after infusion of TNF blockers, a decrease the level of NF-kB translocation in NK cells was observed (Me 27.3 [23.5–39.1] – Me 17.7 [16.5–26.5]; p = 0,03) and an increase in Tregs (Me 18.9 [16.91–20.8] – Me 26.9 [19.4–31.9]; p = 0.0015). Conclusion The level of NF-kB translocation reflects the functional activity of major and small populations of lymphocytes. An increase in activity of Tregs in response to the administration of TNF blockers allows predicting a positive outcome from therapy over the next 6 months. If there is no Tregs reaction in response to the administration of TNF blockers, treatment tactics should be reassessed.

scholarly journals Triplex Hybridization-Based Nanosystem for the Rapid Screening of Pneumocystis Pneumonia in Clinical Samples

2020 ◽  
Vol 6 (4) ◽  
pp. 292
Author(s):  
Luis Pla ◽  
Anna Aviñó ◽  
Ramón Eritja ◽  
Alba Ruiz-Gaitán ◽  
Javier Pemán ◽  
...  
Keyword(s):  
Limit Of Detection ◽  
Pneumocystis Pneumonia ◽  
Rapid Screening ◽  
Diagnostic Tools ◽  
Clinical Samples ◽  
Current Standard ◽  
Promising Alternative ◽  
Nanoporous Anodic Alumina ◽  
Dna Oligonucleotides ◽  
Risk Of Mortality

Pneumocystis pneumonia (PcP) is a disease produced by the opportunistic infection of the fungus Pneumocystis jirovecii. As delayed or unsuitable treatments increase the risk of mortality, the development of rapid and accurate diagnostic tools for PcP are of great importance. Unfortunately, current standard methods present severe limitations and are far from adequate. In this work, a time-competitive, sensitive and selective biosensor based on DNA-gated nanomaterials for the identification of P. jirovecii is presented. The biosensor consists of a nanoporous anodic alumina (NAA) scaffold which pores are filled with a dye reporter and capped with specific DNA oligonucleotides. In the presence of P. jirovecii genomic DNA, the gated biosensor is open, and the cargo is delivered to the solution where it is monitored through fluorescence spectroscopy. The use of capping oligonucleotides able to form duplex or triplex with P. jirovecii DNA is studied. The final diagnostic tool shows a limit of detection (LOD) of 1 nM of target complementary DNA and does not require previous amplification steps. The method was applied to identify DNA from P. jirovecii in unmodified bronchoalveolar lavage, nasopharyngeal aspirates, and sputum samples in 60 min. This is a promising alternative method for the routinely diagnosis of Pneumocystis pneumonia.

scholarly journals The human cytomegalovirus protein UL147A downregulates the most prevalent MICA allele: MICA*008, to evade NK cell-mediated killing

2021 ◽  
Vol 17 (5) ◽  
pp. e1008807
Author(s):  
Einat Seidel ◽  
Liat Dassa ◽  
Corinna Schuler ◽  
Esther Oiknine-Djian ◽  
Dana G. Wolf ◽  
...  
Keyword(s):  
Nk Cells ◽  
Human Cytomegalovirus ◽  
Cell Activation ◽  
Hcmv Infection ◽  
Nk Cell ◽  
Innate Immune ◽  
Target Cells ◽  
Histocompatibility Complex ◽  
Immunosuppressed Patients ◽  
Infected Cells

Natural killer (NK) cells are innate immune lymphocytes capable of killing target cells without prior sensitization. One pivotal activating NK receptor is NKG2D, which binds a family of eight ligands, including the major histocompatibility complex (MHC) class I-related chain A (MICA). Human cytomegalovirus (HCMV) is a ubiquitous betaherpesvirus causing morbidity and mortality in immunosuppressed patients and congenitally infected infants. HCMV encodes multiple antagonists of NK cell activation, including many mechanisms targeting MICA. However, only one of these mechanisms, the HCMV protein US9, counters the most prevalent MICA allele, MICA*008. Here, we discover that a hitherto uncharacterized HCMV protein, UL147A, specifically downregulates MICA*008. UL147A primarily induces MICA*008 maturation arrest, and additionally targets it to proteasomal degradation, acting additively with US9 during HCMV infection. Thus, UL147A hinders NKG2D-mediated elimination of HCMV-infected cells by NK cells. Mechanistic analyses disclose that the non-canonical GPI anchoring pathway of immature MICA*008 constitutes the determinant of UL147A specificity for this MICA allele. These findings advance our understanding of the complex and rapidly evolving HCMV immune evasion mechanisms, which may facilitate the development of antiviral drugs and vaccines.

scholarly journals Does massive  bowel resection in newborns  affect further  immunity in children ?

2020 ◽  
Author(s):  
Katarzyna Sznurkowska ◽  
Anna Borkowska ◽  
Agnieszka Jankowska ◽  
Magdalena Malanowska ◽  
Maciej Zagierski ◽  
...  
Keyword(s):  
T Cells ◽  
Nk Cells ◽  
Bowel Resection ◽  
Clinical Signs ◽  
Peripheral Lymphocyte ◽  
Control Group ◽  
Healthy Children ◽  
Activated T Cells ◽  
Serum Immunoglobulins ◽  
Lymphocyte Populations

Abstract Background Short bowel syndrome (SBS) is defined as the a malabsorptive condition most often caused by massive resection of the small intestine. In children most cases of SBS originate in the newborn period and result from congenital anomalies or necrotizing enterocolitis. Loss of gut mucosa during resection does not only mean loss of absorption surface, but also deprives organism of many immunocompetent cells concentrated in gut associated lymphoid tissue, which is regarded the largest immune organ in humans. Aim of the study: We have aimed to access the influence of bowel resection on adaptive immunity in children, basing on peripheral lymphocyte populations and serum immunoglobulins. Patients and methods: 18 children, who underwent bowel resection in the first month of life and required further home parenteral nutrition were enrolled into the study. 12 healthy children, constituted control group. Based on flow cytometry the following subpopulations of lymphocytes were evaluated: T, B, NK, CD4+, C8 + and activated T cells. Serum immunoglobulins were determined with the use of immunoturbidimetric method. Results The percentage of B lymphocytes was reduced, while the rates of lymphocytes T and CD8 + lymphocytes were higher compared to healthy children. We documented significantly lower absolute count and proportion of NK cells in SBS group than in the control group. Absolute counts of lymphocytes, lymphocytes B, T, CD4 + and percentages of lymphocytes CD4+, and activated T cells inversely correlated with the time after resection. No statistically significant differences were found between the levels of IgA, IgM and IgG in the studied and the control group Conclusions Children with SBS do not present with clinical signs of immunodeficiency as well as deficits in peripheral lymphocyte populations and serum immunoglobulins. Lower number of NK cells in SBS patients compared to healthy children needs to be verified in larger cohort. The tendency of the lymphocyte subpopulations to decrease over time after resection points out the necessity for longer follow- up.

scholarly journals Extent of Cytomegalovirus Replication in the Human Host Depends on Variations of the HLA-E/UL40 Axis

mBio ◽  
2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Hannes Vietzen ◽  
Timo Rückert ◽  
Svenja Hartenberger ◽  
Claudia Honsig ◽  
Peter Jaksch ◽  
...  
Keyword(s):  
Lung Transplantation ◽  
Nk Cells ◽  
Human Cytomegalovirus ◽  
Cell Response ◽  
Nk Cell ◽  
Content Type ◽  
Immunosuppressed Patients ◽  
Hcmv Replication ◽  
Type Gene ◽  
High Level

ABSTRACT Human cytomegalovirus (HCMV) may cause severe infections in lung transplant recipients (LTRs). In response to HCMV infections, a subset of NKG2C+ NK cells expands, which limits HCMV replication and is characterized by high expression of the activating NKG2C/CD94 and absence of the inhibitory NKG2A/CD94 receptor. Both receptors bind to HLA-E, which is stabilized by HCMV-encoded UL40 peptides. HLA-E and UL40 occur as different genetic variants. In this study, we investigated the interplay between the human NK cell response and the infecting HCMV-UL40 strain, and we assessed the impact of HCMV-UL40 and of donor- and recipient-encoded HLA-E*0101/0103 variants on HCMV replication after lung transplantation. We included 137 LTRs displaying either no or low- or high-level (>1,000 copies/ml plasma) viremia. HCMV-UL40 and HLA-E*0101/0103 variants were determined. UL40 diversity was investigated by next-generation sequencing. UL40 peptide-dependent NK cell cytotoxicity was assessed by flow cytometry. Donor-encoded HLA-E*0101/0103 was significantly associated with development of high-level viremia after transplantation (P = 0.007). The HCMV-UL40 variant VMAPRTLIL occurred significantly more frequently in highly viremic LTRs, and the variant VMTPRTLIL occurred significantly more frequently in low-viremic LTRs (P = 0.004). This difference was associated with a better inhibition of NKG2A+ NKG2C− NK cells by VMAPRTLIL (P < 0.001). In LTRs with repeated high-level viremic episodes, HCMV strains with UL40 variants displaying low affinity to the patients’ HLA-E variant emerged over time. The HLA-E-UL40 axis has a substantial impact on the level of HCMV replication in LTRs. The interplay between UL40 peptide variants, the recipient HLA-E status, and the activation of inhibitory NKG2A+ NKG2C− cells is of major importance for development of high-level viremia after lung transplantation. IMPORTANCE Infection with human cytomegalovirus (HCMV) is associated with substantial morbidity in immunosuppressed patients and after congenital infections. Therefore, development of a vaccine against HCMV is a main public health priority. Revealing the complex interaction between HCMV and host responses, is of utmost importance for understanding viral pathogenesis and for vaccine design. The present data contribute to the understanding of HCMV-specific host immune responses and reveal specifically the interaction between HLA-E and the virus-encoded UL40 peptide, which further leads to a potent NK cell response. We demonstrate that this interaction is a key factor for reduction of virus replication in immunosuppressed patients. We further show that distinct naturally occurring HCMV-UL40 variants reduce the activation of a specific subpopulation of host NK cells and thereby are associated with high-level viremia in the patients. These findings will allow the characterization of patients at risk for severe HCMV infection and contribute to strategies for HCMV vaccine development.

Subtyping lymphocytes in peripheral blood by immunoperoxidase labeling and light scatter/absorption flow cytometry.

1985 ◽  
Vol 31 (9) ◽  
pp. 1481-1486 ◽  
Author(s):  
Y R Kim ◽  
G Martin ◽  
L Paseltiner ◽  
H Ansley ◽  
L Ornstein ◽  
...  
Keyword(s):  
Lymphocyte Subpopulations ◽  
Light Scatter ◽  
Accuracy And Precision ◽  
Halogen Light ◽  
Halogen Light Source ◽  
Endogenous Peroxidase ◽  
Immunoperoxidase Labeling ◽  
Ethanesulfonic Acid ◽  
Lymphocyte Populations ◽  
Specific Amount

Abstract Lymphocyte subpopulations in a whole-blood sample can be detected by adapting mouse monoclonal antibodies (MAbs) and peroxidase (EC 1.11.1.7) labeling to a flow cytometer equipped with a tungsten-halogen light source and scatter/absorption optics (Technicon H6000). In the optimized cytochemical conditions each cell population generates a distinct, well-separated cluster, for accurate "thresholding" of the surface-antigen negative and positive lymphocyte populations in the presence of other leukocytes. After reaction with MAb, the erythrocytes are lysed, and the lymphocytes and other leukocytes are fixed. Biotinylated anti-mouse IgG, used as a bridge, amplifies the response from the avidin-peroxidase label. Granulocytes and monocytes, which have high endogenous peroxidase activity, and the labeled lymphocytes are stained in a specific amount of hydrogen peroxide plus 4-chloro-1-naphthol in 4-(2-hydroxyethyl)-1-piperazine-ethanesulfonic acid buffer. Accuracy and precision are equivalent to those of flow cytometers that measure immunofluorescence (e.g., Ortho Spectrum III), as demonstrated with OKT3, OKT4, OKT8, OKT11, and Leu 12 MAbs.

Mechanistic differences in NK cell cytolytic activity in treadmill-trained and chronic ethanol-consuming mice

1994 ◽  
Vol 76 (5) ◽  
pp. 2031-2036 ◽  
Author(s):  
S. E. Blank ◽  
J. O. Johansson ◽  
L. J. Pfister ◽  
R. M. Gallucci ◽  
E. G. Lee ◽  
...  
Keyword(s):  
Nk Cells ◽  
Nk Cell ◽  
Regional Distribution ◽  
Cell Activity ◽  
Cytolytic Activity ◽  
Lymphocyte Subpopulations ◽  
Moderate Intensity ◽  
Nk Cell Activity ◽  
Paracrine Regulation ◽  
Nylon Wool

The present study was undertaken to investigate mechanisms contributing to differences in natural killer (NK) cell activity in moderately endurance-trained and ethanol-consuming mice. Independent of ethanol exposure, NK cell activity in nylon wool-nonadherent (NWNA) splenocytes is lower in trained than in sedentary control mice (Blank et al. J. Appl. Physiol. 72: 8–14, 1992). Reduced activity may result from a generalized loss of cytolytically active cells, redistribution of NK cells from the spleen to other body compartments, or disruption of paracrine regulation of NK cells after removal of nylon wool-adherent cells. To examine these possibilities, NK cell cytolytic activity was determined in nonenriched splenocytes from treadmill-trained and ethanol-consuming mice. Lymphocyte subpopulations in nonenriched splenocytes and NWNA splenocytes were also compared. Peripheral blood lymphocyte subpopulations were determined to examine combined effects of training and ethanol intake on regional distribution of lymphocytes in blood and spleen. NK cell activity in nonenriched splenocytes from trained water-drinking mice was not reduced compared with that in sedentary mice; rather, cytolytic activity was moderately enhanced (17% increase in lytic units, P < 0.05). Training did not change percentages of T-cells, B-cells, and NK [NK1.1+ and large granular lymphocytes (LGL-1+)] cells or the LGL/NK ratio in the spleen and blood. NK cell cytolytic activity was significantly reduced in nonenriched splenocytes from ethanol-consuming mice, independent of training. These findings support the hypothesis that moderate-intensity endurance training influences splenic NK cell function by modulating paracrine regulation of NK cells.(ABSTRACT TRUNCATED AT 250 WORDS)

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