Associations of T helper 1, 2, 17 and regulatory T lymphocytes with mortality in severe sepsis

Objective and design

T helper 17 (Th17) and regulatory T (T_reg) lymphocytes might play important roles in patients with severe sepsis. The association of Th17 or T_reg lymphocytes with survival is also unclear.

Methods

Eighty-seven patients with severe sepsis were enrolled from our intensive care units between August 2008 and July 2010. Leukocyte antigens and clinical data were determined on day 1 in all patients and on day 7 in first-year patients.

Results

The percentages in peripheral blood mononuclear cells (PBMCs) and circulatory counts of CD4⁺ and CD8⁺ lymphocytes in survivors were higher than those in non-survivors. Th1/CD4⁺ ratios and circulatory Th1 lymphocyte counts in survivors were higher than in non-survivors. Absolute counts of Th17 and T_reg lymphocytes in survivors were higher than in non-survivors. The percentages of CD4⁺ and CD8⁺ in survivors’ PBMCs were increased after 6 days. Th17/CD4⁺ ratios and circulatory Th17 lymphocyte counts in survivors were increased after 6 days.

Conclusions

Higher Th1 differentiation and total CD4⁺ T lymphocyte counts were associated with higher survival. The association of circulatory Th17 and T_reg lymphocytes with mortality in severe sepsis may be due to the change in total CD4⁺ T lymphocytes. In survivors, Th17 differentiation and counts were restored.     

Effect of 6-day intense Kendo training on lymphocyte counts and its expression of CD95

This study examines the effects of 6-day intensive training on lymphocyte counts and their expression of CD95. Eight healthy Kendo athletes underwent 6-day Kendo training of about 310 min each day. Blood samples were collected at 2 weeks before (PRE), the first day (Day 1), third day (Day 3), fifth day (Day 5), and 1 week after the training period (POST) to determine lymphocyte counts and CD95 expression on CD95 lymphocytes (CD4⁺, CD8⁺) using flow cytometry. The total lymphocyte counts were significantly lower at Day 3 than at PRE. The CD8⁺ cell counts were significantly lower at Day 3 than at PRE. The percentage of CD95⁺ lymphocytes was significantly higher at Day 1 and Day 3 than at PRE. The percentage of CD8⁺CD95⁺ cells did not change significantly. The total lymphocyte counts decreased and a concomitant increase of CD95⁺ lymphocyte was observed, whereas the decrease in CD8⁺ cell counts was not associated with the increase in CD8⁺CD95⁺ cells. Therefore, short-term high-intensity exercise induced a decrease in the T lymphocyte counts without increasing in CD95⁺ expression.     

Accumulation of CD5<Superscript>+</Superscript>CD19<Superscript>+</Superscript> B lymphocytes expressing PD-1 and PD-1L in hypertrophied pharyngeal tonsils

Programmed death-1 (PD-1) is one of the most important inhibitory co-receptors expressed predominantly on activated T and B lymphocytes whose expression could be sustained by permanent antigenic stimulation accompanying chronic or recurrent tonsillitis. The expression of PD-1 and PD-1L was analyzed using flow cytometry on hypertrophied tonsils collected from 57 children. We observed high expression of PD-1 and PD-1L on certain lymphocytes subpopulations of hypertrophied tonsils; among T cells, the expression of PD-1 on protein level was higher on CD4⁺ cells (70.3 %) than on CD8⁺ cells (35 %). Interestingly, a limited expression of PD-1 was observed on CD19⁺ B lymphocytes (6.5 %), while CD5⁺CD19⁺ B cells overexpressed PD-1 (52.5 %). Moreover, the expression of PD-1L was also higher on CD5⁺CD19⁺ B cells (16.5 %) than on CD19⁺ B cells (3.5 %) and on CD4⁺ T cells (20 %) than on CD8⁺ T cells (10 %). PD-1 and PD-1L expressions correlated only on CD5⁺CD19⁺ cells. In conclusion, high expression of PD-1 and PD-1L on T and B cells could represent hallmark of immune system adaptation to chronic antigenic exposition in patients with tonsillitis.     

Adoptive Cellular Therapy using Cells Enriched for NKG2D+CD3+CD8+T Cells after Autologous Transplantation for Myeloma

The number of circulating lymphocytes on day 15 after transplantation correlates with improved survival in patients with myeloma, but the lymphocyte subset responsible is unknown. NKG2D is a natural killer (NK) cell activating receptor that mediates non-MHC restricted and TCR-independent cell lysis. Our preliminary results indicate that CD3⁺CD8⁺ T cells expressing NKG2D may be a critical lymphocyte population. A phase II trial examined the feasibility of infusing ex vivo-expanded cells enriched for NKG2D⁺CD3⁺CD8⁺ T cells at weeks 1, 2, 4, and 8 after an autologous transplantation. In addition, low-dose IL-2 (6 × 10⁵ IU/m²/day) was administered for 4 weeks, beginning on the day of transplantation. Twenty-three patients were accrued and 19 patients are evaluable. There were no treatment-related deaths. All patients completed their course of IL-2 and demonstrated normal engraftment. When compared with patients with myeloma who underwent transplantation not receiving posttransplantation immune therapy, the treated patients demonstrated an increase in the number of circulating NKG2D⁺CD3⁺CD8⁺ T cells/μL (P < .004), CD3⁺CD8⁺ T cells/μL (P < .04), CD3⁺CD8⁺CD56⁺ T cells/μL (P < .004), and NKG2D⁺CD3^-CD56⁺ T cells/μL (P < .003). Myeloma cell-directed cytotoxicity by the circulating mononuclear cells increased after transplantation (P < .002). When compared to posttransplantation IL-2 therapy alone in this patient population, the addition of cells enriched for NKG2D⁺CD3⁺CD8⁺ T cells increased tumor-specific immunity, as demonstrated by enhanced lysis of autologous myeloma cells (P = .02). We postulate that this regimen that increased the number and function of the NKG2D⁺CD3⁺CD8⁺ T cells after transplantation may improve clinical outcomes by eliminating residual malignant cells in vivo.     

Immune Reconstitution in Pediatric Aplastic Anemia after Allogeneic Hematopoietic Stem-cell Transplantation

Background: Previous studies had revealed that immune reconstitution (IR) after allogeneic hematopoietic stem-cell transplantation (allo-HSCT) affected the clinical prognosis of patients. However, few studies were based on pediatric patients and patients with aplastic anemia (AA). The purpose of this research was to analyze IR of pediatric AA after HSCT and further explore its clinical prognostic value.Methods: The whole of 61 pediatric patients with AA who underwent HSCT were enrolled. Lymphocyte subsets count in peripheral blood, CD4⁺/CD8⁺ T cell ratio, and serum concentration of immunoglobulins were detected using flow cytometry at regular intervals after HSCT.Results: Innate immunity recovered faster than adaptive immunity, T lymphocytes recovered faster than B lymphocytes. The number of transfused CD34⁺ cells and the implantation time of ANC significantly affected the early rapid IR of CD3⁺ T cells. The degree of HLA site coincidence significantly affected the early rapid IR of CD19⁺ B cells. The number of transfused MNC and CD34⁺ cells significantly affected the early rapid IR of CD56⁺ NK cells. The overall survival (OS) and failure-free survival (FFS) of CD56⁺ NK cells in early rapid IR group were higher than those in non-IR group. The CD3⁺ T cell early rapid IR group and CD8⁺ T cell early rapid IR group had higher OS than the non-IR group.Conclusion: Early rapid IR after HSCT is a good predictor of clinical prognosis in children with AA. This study provides a reasonable prediction for early rapid IR, which may improve clinical outcomes of children.     

Depletion of Alloreactive Donor T Lymphocytes by CD95-Mediated Activation-Induced Cell Death Retains Antileukemic,Antiviral, and Immunoregulatory T Cell Immunity

In allogeneic hematopoietic stem cell transplantation (AHSCT) graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effect are closely but not invariably linked. Thus, harnessing donor lymphocyte mediated GVL immunity and separating it from GVHD is of particular interest. Based on results obtained in murine models we have explored the CD95-mediated activation-induced cell death (AICD) strategy to selectively deplete alloreactivity in human donor T lymphocytes in vitro. Following stimulation of CD3⁺ T cells isolated from HLA-A¹0201-positive donors with HLA or minor histocompatibility antigen mismatched hematopoietic or nonhematopoietic cells in the presence of agonistic anti-CD95 antibody, we achieved efficient and selective allodepletion across major and minor histocompatibility mismatched barriers. Residual alloreactivity was in the range of 10% and 25% using hematopoietic cells and primary keratinocytes as alloantigen-presenting cells, respectively. CD8⁺ T cells specific for HLA-A¹0201-associated cytomegalovirus (CMV), Epstein-Barr virus (EBV), and Wilms tumor 1 peptide epitopes were retained at significant numbers within the allodepleted donor lymphocyte subsets. Additionally, CD4⁺ FoxP3⁺ regulatory T cells persisted after the allodepletion procedure. Our results show that AICD induced by an agonistic anti-CD95 antibody might be useful to generate allodepleted donor lymphocyte products with preserved beneficial immune functions for patients undergoing AHSCT.     

Sequential appearance of γ/δ- and α/β-bearing T cells in the peritoneal cavity during an i.p. infection with Listeria monocytogenes

To search for a potential role of T cell antigen receptor (TcR) γ/β-bearing cells in host-defense against Listeria monocytogenes, we analyzed the sequential appearance of γ/δ and α/β T cell in the peritoneal exudate cells (PEC) during an i.p. infection with sublethal dose (2 × 10³) of viable Listeria organisms in mice. The PEC on day 1 after the infection consisted of 48% macrophages and 50% lymphocytes, most of which were surface IgM⁺ (B) cells. The number of PEC increased to the maximal level by day 3. The PEC at this stage contained an appreciable number of CD3⁺ T cells in addition to a large number of macrophages. Of the CD3⁺ cells, the proportion of CD4^?CD8^? cells, most of which expressed no TcR α/β, increased to the maximal level on day 3 after the infection. In correlation with an increased number of CD3⁺CD4^?CD8^?TcR α/β^? cells, high level of TcR γ/δ chain gene messages was detected in the nonadherent population of the PEC on this stage. On the other hand, the PEC on day 8 contained an increased number of CD4⁺CD8^? and CD4^?CD8⁺ cells which expressed TcR α/β chain on their surface. These results suggest that the γ/δ T cells precede the α/β T cells in appearance during listerial infection. The γ/β T cells may be involved at the first line of the host-defense against Listeria.     

Decrease in intrahepatic CD56+ lymphocytes in gastric and colorectal cancer patients with liver metastases

Gulubova M, Manolova I, Kyurkchiev D, Julianov A, Altunkova I. Decrease in intrahepatic CD56⁺ lymphocytes in gastric and colorectal cancer patients with liver metastases. APMIS 2009; 117: 870–9. The aim of the study was to examine the main intrahepatic lymphocyte subpopulations, namely CD3⁺ lymphocytes, natural killer (NK)‐like T lymphocytes (NKT) expressing the CD3⁺ CD56⁺ phenotype, CD56⁺ NK cells, CD4⁺, and CD8⁺ T cells in livers of patients with gastric and colorectal cancer with and without hepatic metastases. The proportion of each lymphocyte subset was determined in 34 patients with gastric or colorectal cancer (18 with and 16 without liver metastasis) by two‐color flow cytometry after extraction of hepatic mononuclear cell fraction. The distribution of lymphocyte subpopulations in selected areas of liver metastases and adjacent liver tissue was evaluated using immunohistochemistry for CD4, CD8, and CD56. Flow cytometry analysis revealed a significant decrease in the proportion of CD3⁺ CD56⁺ cells in metastatic livers, but not in nonmetastatic livers (11.9 ± 10.3 vs 24.2 ± 13.6%, p = 0.02). The percentage of intrahepatic CD3^?CD56⁺ cells was also decreased in patients with metastases compared to those without (10.1 ± 11.6 vs 16.6 ± 8.9%, p = 0.039). Immunohistochemically, three types of lymphocytes (CD4⁺, CD8⁺, and CD56⁺) were present in the metastatic tissue, although the number of CD56⁺ cells was almost twice lower. We found a low prevalence of tumor‐infiltrating CD4⁺, CD8⁺, and CD56⁺ cells in livers with multiple metastases, whereas in cases with solitary metastasis a higher degree of lymphocyte infiltration was observed. The number of CD3^?CD56⁺ and CD3⁺ CD56⁺ cells was decreased in metastatic livers compared to those unaffected by metastases. Therefore the prevalence of tumor‐infiltrating lymphocytes seems to be related to the progression of metastatic liver disease. Depletion of hepatic innate lymphocytes may reveal susceptibility to metastatic liver disease and could be a reason for the escape of metastatic cells from the mechanisms of liver immune control.     

Phenotypic characterization of T cells in bronchoalveolar lavage fluid (BALF) and peripheral blood of patients with diffuse panbronchiolitis; the importance of cytotoxic T cells

We investigated the contribution of T cells in diffuse panbronchiolitis (DPB) by identifying T cell subsets in BALF of 36 patients with DPB, before and after long-term treatment with macrolide antibiotics, and 16 healthy control subjects. The percentages of lymphocytes and CD3⁺γδ⁺ cells in BALF of DPB patients and control subjects were similar, but the absolute number of these cells was higher in DPB patients. Treatment resulted in a significant reduction in the absolute number of these cells. A further two-colour analysis of T cell subsets in BALF showed a significantly higher ratio and number of CD8⁺HLA-DR⁺ cells in DPB patients. Treatment resulted in a significant reduction of activated T cells. Most BALF CD8⁺ cells were CD8⁺CD11b⁻ cytotoxic T cells. The number of these cells in BALF of DPB patients (26.69 ± 5.86 × 10³/ml) was higher than the control (2.02 ± 0.38 × 10³/ml; P< 0.001), and a significant reduction was observed after treatment (7.69 ± 2.59 × 10³/ml; P< 0.01). The number of CD4⁺ cells was also higher in DPB patients than in controls, and most were CD4⁺CD29⁺ memory T cells. However, treatment did not influence the number of these cells. The number of lymphocytes, CD3⁺γδ⁺, CD8⁺CD11b⁻, CD8⁺HLA-DR⁺, and CD4⁺CD29⁺ cells was higher in patients with bacterial infection than in those without bacterial infection, and interestingly, macrolide therapy reduced the number of lymphocytes, CD3⁺γδ⁺, CD8⁺CD11b⁻ and CD8⁺HLA-DR⁺ cells, irrespective of bacterial infection. In peripheral blood, the percentage of CD8⁺HLA-DR⁺ cells was also higher in DPB patients than in healthy subjects, and significantly decreased after treatment. The percentage of CD8⁺CD11b⁻ cells in peripheral blood was similar in DPB patients and normal subjects, and treatment significantly reduced the percentage of these cells. Finally, the expression of the adhesion molecules CD11a/CD18 (α/β-chains of LFA-1) on lung CD3⁺ cells and CD49d (α-chain of VLA) on lung CD4⁺ cells was enhanced compared with that on peripheral blood in DPB patients. Our results suggest that elevation of memory T cells and activation of CD8⁺ cells, mainly cytotoxic T cells, in the airway lumen of DPB patients may contribute to chronic bronchial inflammation, possibly through up-regulation of adhesion molecules. Our findings also indicate that macrolide antibiotics may have a direct or indirect suppressive effect on cytotoxic T cells, and as such, reduce inflammation and improve clinical condition.     

Lymphocyte subsets in distinct lung compartments show a different ability to produce interferon-gamma (IFN-γ) during a pulmonary immune response

Lymphocytes play an important immunoregulatory role in pulmonary immune responses. By releasing cytokines they can control the cell–cell communication of other participating cells. Although it is well established that the lung lymphocytes, localized in distinct compartments, differ in their subset composition, little is known about cytokine production in these compartments during immune responses. Lewis rats were immunized by intravenous administration of sheep erythrocytes on day 0 and day 7 and challenged intratracheally with sheep erythrocytes on day 10. Four days after intratracheal (i.t.) challenge the composition of lymphocyte subsets (CD2⁺, CD4⁺, CD8⁺, B cells, natural killer (NK) cells) in the spleen, blood, lung perfusate, lung tissue and bronchoalveolar lavage fluid (BALF) was characterized, and intracellular IFN-γ was detected in these subsets by flow cytometry. Comparing control and immunized animals, no changes were found in lymphocyte numbers, subsets or the percentage of IFN-γ-producing lymphocytes in the spleen, blood and lung perfusate. In lung tissue and BALF, however, the absolute number of all lymphocyte subsets and the percentage of IFN-γ-producing lymphocytes were increased. When the lymphocyte subsets were analysed an increased percentage of IFN-γ-producing T cells was found in lung tissue (4.5 ± 0.6% versus 12.8 ± 1.1%) and in BALF (7.8 ± 1.4% versus 14.8 ± 1.9%) of immunized animals opposed to controls, this increase being seen in both CD4⁺ and CD8⁺ cells. Thus, there is an accumulation of T cells with an increased potential to produce IFN-γ in the lung interstitium and the bronchoalveolar space during pulmonary immune responses.     

CD28 expression is increased in venom allergic patients but is not modified by specific immunotherapy

Background Recognition of antigen bound to the major histocompatibility complex by the T cell receptor is insufficient to lead to T cell proliferation and effector function, which require co-stimulatory signals, such as those resulting from the interaction of CD28 expressed on T lymphocytes and CD80/CD86 expressed on APCs. Lack of interaction between these accessory molecules during antigen stimulation leads to a state of antigen-specific lymphocyte unresponsiveness. Previous studies have shown that rush venom immunotherapy decreases venom-specific T cell proliferation very early after the initiation of the rush. Objective In order to see whether this hyporeactivity was associated with a down regulation of accessory molecules, we studied CD28 surface expression on T lymphocytes from 10 non-atopic controls and from 10 non-atopic patients undergoing rush venom immunotherapy. Methods Peripheral blood samples were collected before the rush (day 0), at the end of the rush (day 1), at day 15 and at day 45. CD28 expression was analysed using flow cytometry with double labelling of the CD4⁺ and CD8⁺ lymphocyte subpopulations. Results At baseline CD28 was expressed at a higher level on T lymphocytes from allergic patients than from control subjects (P < 0.04), and in particular on the CD8 subset (P < 0.01), reflecting a decrease in the suppressive CD8⁺CD28^– subpopulation. No changes were found in the percentages of total CD28⁺ T cells, CD4⁺ CD28⁺ or CD8⁺CD28⁺ cells at the different time points after the initiation of immunotherapy. Conclusion These results suggest that the CD28 pathway is probably involved in the development of allergic reactions, but at least at the phenotypic level, CD28 expression remained unchanged after rush venom immunotherapy.     

Involvement of (IgG and IgM)-secreting B lymphocytes in severity of autoimmune hepatitis type 1

Autoimmune hepatitis type 1 (AIH1) is an autoimmune disease attacks the liver and characterized by periportal inflammation, elevated immunoglobulins, and autoantibodies. The central role of B lymphocyte in pathogenicity of AIH1 is unclear. Here, the effect of antibody-secreting cells activity in terms of number of plaque-forming cells (PFC) on severity of AIH1 was evaluated. The high number of PFC-(IgG and IgM) in peripheral blood of patients with AIH1 was observed and this was concomitant with increase in the number of CD4⁺ T lymphocyte, immunoglobulin (Ig) (IgG and IgM) concentrations, and levels of liver function tests (LFTs). However, the negative correlation (r < ?0.5, P < 0.05) between the numbers of PFC-(IgG and IgM) and CD8⁺ T lymphocytes was reported here. The present study showed the positive relationship between the concentrations of Ig (IgG and IgM) and levels of LFTs (r > +0.5, P < 0.05). The high expression of IL-10 mRNA was found in the tissue culture of peripheral blood lymphocytes obtained from patients with AIH1 as compared with that isolated from control group (P < 0.05). The current study proved the direct role of (IgG and IgM)-secreting cells in severity of AIH1. This was associated with CD4⁺ cell numbers and IL-10 mRNA expression, and mediated by IgG and IgM.     

Immune activation in the context of HIV infection

Our objective was to study whether CD4⁺ or CD8⁺ T cells expressing particular T cell receptors (TCR) would accumulate in the lungs of patients with allergic asthma following allergen exposure. We thus analysed the TCR Vα and Vβ gene usage of CD4⁺ and CD8⁺lung and peripheral blood lymphocytes (PBL) of eight patients with allergic asthma before and 4 days after inhalation challenge with the relevant allergen. Lung cells obtained by bronchoalveolar lavage (BAL) and paired PBL samples were analysed by flow cytometry using a panel of anti-TCR V-specific monoclonal antibodies that encompass ≈ 50% of the T cell repertoire. Lung-limited T cell expansions were recorded in both the CD4⁺and the CD8⁺subsets. In BAL CD8⁺, out of a total of 126 analyses, the number of T cell expansions increased from two to 11 after challenge, some of them dramatic. In BAL CD4⁺the frequency of expansions was moderately increased already before challenge, but remained unchanged. A few expansions that tended to persist were noted in PBL CD8⁺. When analysing the overall change in TCR V gene usage the largest changes were also recorded in the BAL CD8⁺subset. Specific interactions between T cells and antigens may lead to an increased frequency of T cells using selected TCR V gene segments. In this study we demonstrate that following allergen bronchoprovocation in allergic asthmatic subjects, T cell expansions preferentially emerge in the lung CD8⁺T cell subset.     

Circulating CD4+CD8+ T lymphocytes in patients with Kawasaki disease

We serially monitored cell surface antigen expression on mononuclear cells in peripheral blood isolated from patients with Kawasaki disease (KD), and found, for the first time, that a markedly increased number of CD4⁺CD8⁺ T lymphocytes was present in some of the patients (11 of the 24 cases). The cases of five of these 11 patients were complicated with coronary artery lesion (CAL); the 13 patients with normal numbers of CD4⁺CD8⁺ T lymphocytes did not have CAL. The patients' age, sex and grade of systemic inflammation evaluated by peripheral leucocyte count and serum C-reactive protein levels were not correlated to the number of CD4⁺CD8⁺ T lymphocytes. Other cell surface antigen characteristics of the CD4⁺CD8⁺ T lymphocytes included CD3⁺, CD45RA⁺, CD45RO⁺, CD16^?, and HLA-DR⁺. These results indicate that the surface antigen characteristics of the KD peripheral blood examined were the same as those of Epstein–Barr virus infection without CD45RA⁺. These findings provide useful information for the analysis of the pathogenesis of KD.     

Early Changes in Frequency of Peripheral Blood Lymphocyte Subpopulations in Severe Traumatic Brain‐Injured Patients

Infections are leading causes of increased morbidity and mortality of severe traumatic brain‐injured (STBI) patients. The mechanism underlying the susceptibility to the infections is still unexplained. The purpose of the study was to investigate changes in frequency of leucocytes subpopulations in peripheral blood of patients with STBI during the course of intensive care treatment. Twenty patients with STBI were included in the study. Healthy age‐ and sex‐ volunteers served as control. Peripheral blood samples were taken from these patients at day 1, 4 and 7, and peripheral blood mononuclear cells (PBMC) were isolated. The percentage of T, B lymphocyte, NK and NKT cells as well as monocytes was analysed by simultaneous detection of surface antigens using fluorochrome‐conjugated monoclonal antibodies. The two major subsets of T lymphocytes (CD3⁺CD56^?CD4⁺ and CD3⁺CD56^?CD8⁺) and NK cells (CD3^?CD56^+dim and CD3^?CD56^+bright) were also analysed by flow cytometry. Extracranial infections were presented in 55% patients with STBI. At day 4, the percentage of T lymphocytes with cytotoxic phenotype significantly diminished and their numbers restored at day 7. The frequency of NKT cells showed the identical time‐dependent pattern, whereas the percentage of NK cells diminished on day 4 but did not restore after 7 days. The frequency of B lymphocytes did not change significantly during the time investigated, whereas the percentage of monocytes increased immediately after the injury and gradually diminished. The decrease in cells with cytotoxic phenotype might explain high incidence of susceptibility to infection of patients with STBI.     

Etanercept Downregulates the Th17 Pathway and Decreases the IL-17+/IL-10+ Cell Ratio in Patients with Psoriasis Vulgaris

Purpose

To evaluate circulating and lesional CD4⁺ and CD8⁺ cells belonging to Th1, Th2, and Th17 patterns as well as IL-10⁺ cells before and after a 12-week lasting course with etanercept or acitretin in patients with psoriasis.

Methods

15 patients were given etanercept 50 mg twice weekly and 15 patients acitretin 0,4 mg/kg/day, both for 12 weeks. At the baseline and at the end of the treatment, blood and skin samples were taken to investigate IL-4, IL-8, IL-10, IL-17, and IFN-γ-producing CD4⁺ and CD8⁺ cells. As controls, 10 healthy controls (HC) and 6 atopic dermatitis (AD) patients were included into the study.

Results

Psoriasis patients showed augmented IL-17- and IL-8-producing CD4⁺ cells in the blood than HC and AD patients. In the skin lesions, IL-17⁺ cells were more represented in psoriasis than in AD, while the number of IL-4-producing cells was reduced in psoriasis patients than in AD ones. Etanercept was able to significantly reduce the number of IL-17- and IL-8-producing CD4⁺ and CD8⁺ cells both in skin and blood, as well as to augment the proportion of IL-10-producing CD4⁺ cells in the skin of psoriatic patients, while acitretin was not.

Conclusions

Our results confirmed the role of Th17 cells in the pathogenesis of psoriasis. Etanercept, but not acitretin, was able to downregulate the Th17 pathway and to increase the percentages of IL-10-producing cells in the skin.     

Epstein–Barr virus‐specific CD8+ T lymphocytes from diffuse large B cell lymphoma patients are functionally impaired

Epstein–Barr virus (EBV) is a persistent virus with oncogenic capacity that has been implicated in the development of aggressive B cell lymphomas, primarily in immunosuppressed individuals, although it can be present in immunocompetent individuals. Changes in the function and clonal diversity of T lymphocytes might be implied by viral persistence and lymphoma development. The aim of the present study was to evaluate the frequency, phenotype, function and clonotypical distribution of EBV‐specific T cells after peripheral blood stimulation with a virus lysate in newly diagnosed patients with diffuse large B cell lymphoma (DLBCL) aged more than 50 years without prior histories of clinical immunosuppression compared with healthy controls. Our results showed impaired EBV‐specific immune responses among DLBCL patients that were associated primarily with decreased numbers of central and effector memory CD8⁺ T lymphocytes. In contrast to healthy controls, only a minority of the patients showed CD4⁺/tumour necrosis factor (TNF)‐α⁺ T cells expressing T cell receptor (TCR)‐Vβ17 and CD8⁺/TNF‐α⁺ T cells with TCR‐Vβ5·2, Vβ9 and Vβ18 in response to EBV. Notably, the production of TNF‐α was undetectable among TCR‐Vβ5·3⁺, Vβ11⁺, Vβ12⁺, Vβ16⁺ and Vβ23⁺ CD8⁺ T cells. In addition, we observed decreased numbers of CD4⁺/TNF‐α⁺ and CD8⁺/TNF‐α⁺, CD8⁺/interleukin (IL)‐2⁺ and CD8⁺/TNF‐α⁺/IL‐2⁺ T lymphocytes in the absence of T cells capable of producing TNF‐α, IL‐2 and IFN‐γ after EBV stimulation simultaneously. Moreover, DLBCL patients displayed higher IL‐10 levels both under baseline conditions and after EBV stimulation. These findings were also observed in patients with positive EBV viral loads. Prospective studies including a large number of patients are needed to confirm these findings.     

CD4+CD25+Foxp3+ Regulatory T Cells Contribute in Liver Fibrosis Improvement with Interferon Alpha

The aim of this study is to investigate the optimal dose, treatment time, and possible immunologic mechanisms of interferon alpha (IFN-α) in the treatment of liver fibrosis. Mice were injected intraperitoneally with 10 % carbon tetrachloride to induce liver fibrosis, except in the normal control group. The experimental mice were randomly divided into four groups: physiological saline group, 20 U/gb wt IFN-α group, 40 U/gb wt IFN-α group, and 60 U/gb wt IFN-α group. After 3 and 6 weeks, type I collagen was detected in liver by hematoxylin and eosin (HE) stain, Masson’s trichrome stain, and immunohistochemical staining. The number of CD8⁺ T cells, the number of CD4⁺CD25⁺Foxp3⁺ Tregs and the activation of CD4⁺ T cells were detected in liver and spleen. Beneficial effects were observed in the 40 U/gb wt IFN-α group by pathological analysis. The number of CD8⁺ T cells in the liver was significantly lower in mice receiving middle-dose IFN-α therapy as compared to mice receiving physiological saline (P?<?0.05), while CD4⁺CD25⁺Foxp3⁺ Tregs and activation of CD4⁺ T cells in the liver were significantly higher in the therapeutic group than in the physiological saline group (P?<?0.05). CD8⁺ T cells (r?=?0.3796) and activated CD4⁺ T cells (r?=?0.2437) were found to be positively correlated with the degree of liver fibrosis. CD4⁺CD25⁺Foxp3⁺ Tregs (r?=??0.7932) was found to be negatively correlated with the degree of liver fibrosis. IFN-α can inhibit liver fibrosis following 6 weeks of middle-dose IFN-α therapy by upregulating CD4⁺CD25⁺Foxp3⁺ Tregs and suppressing CD8⁺ T cells.     

Translational Mini‐Review Series on Immunology of Vascular Disease: Accelerated atherosclerosis in vasculitis

The cutaneous leucocyte‐associated antigen receptor (CLA) can direct Leishmania‐specific T lymphocytes towards inflamed skin lesions. Homing receptors [CLA, lymphocyte‐associated antigen 1 (LFA‐1) or CD62L] were analysed in lymphocytes from blood and cutaneous leishmaniasis (CL) lesions. CL patients with active lesions (A‐CL) presented lower levels of T lymphocytes expressing the CLA⁺ phenotype (T CD4⁺ = 10·4% ± 7·5% and T CD8⁺ = 5·8% ± 3·4%) than did healthy subjects (HS) (T CD4⁺ = 19·3% ± 13·1% and T CD8⁺ = 21·6% ± 8·8%), notably in T CD8⁺ (P < 0·001). In clinically cured patients these percentages returned to levels observed in HS. Leishmanial antigens up‐regulated CLA in T cells (CLA⁺ in T CD4⁺ = 33·3% ± 14·1%; CLA⁺ in T CD8⁺ = 22·4% ± 9·4%) from A‐CL but not from HS. An enrichment of CLA⁺ cells was observed in lesions (CLA⁺ in T CD4⁺ = 45·9% ± 22·5%; CLA⁺ in T CD8⁺ = 46·4% ± 16·1%) in comparison with blood (CLA⁺ in T CD4⁺ = 10·4% ± 7·5%; CLA⁺ in T CD8⁺ = 5·8% ± 3·4%). Conversely, LFA‐1 was highly expressed in CD8⁺ T cells and augmented in CD4⁺ T from peripheral blood of A‐CL patients. In contrast, CD62L was not affected. These results suggest that Leishmania antigens can modulate molecules responsible for migration to skin lesions, potentially influencing the cell composition of inflammatory infiltrate of leishmaniasis or even the severity of the disease.     

Phenotype, functions and fate of adoptively transferred tumor draining lymphocytes activated ex vivo in mice with an aggressive weakly immunogenic mammary carcinoma

Background

Regression of established tumors can be induced by adoptive immunotherapy with tumor draining lymph node lymphocytes activated with bryostatin and ionomycin. We hypothesized that tumor regression is mediated by a subset of the transferred T lymphocytes, which selectively infiltrate the tumor draining lymph nodes and proliferate in vivo.

Results

Adoptive transfer of B/I activated tumor draining lymphocytes induces regression of advanced 4T1 tumors, and depletion of CD8, but not CD4 T cells, abrogated tumor regression in mice. The predominant mediators of tumor regression are CD8+ and derived from CD62L^- T cells. Transferred lymphocytes reached their peak concentration (10.5%) in the spleen 3 days after adoptive transfer and then rapidly declined. Adoptively transferred cells preferentially migrated to and/or proliferated in the tumor draining lymph nodes, peaking at day 5 (10.3%) and remained up to day 28. CFSE-stained cells were seen in tumors, also peaking at day 5 (2.1%). Bryostatin and ionomycin-activated cells proliferated vigorously in vivo, with 10 generations evident in the tumor draining lymph nodes on day 3. CFSE-stained cells found in the tumor draining lymph nodes on day 3 were 30% CD8⁺, 72% CD4⁺, 95% CD44⁺, and 39% CD69⁺. Pre-treatment of recipient mice with cyclophosphamide dramatically increased the number of interferon-gamma producing cells.

Conclusions

Adoptively transferred CD8+ CD62L^low T cells are the principal mediators of tumor regression, and host T cells are not required. These cells infiltrate 4T1 tumors, track preferentially to tumor draining lymph nodes, have an activated phenotype, and proliferate in vivo. Cyclophosphamide pre-treatment augments the anti-tumor effect by increasing the proliferation of interferon-gamma producing cells in the adoptive host.