COVID-19 pneumonia: CD8+ T and NK cells are decreased in number but compensatory increased in cytotoxic potential.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is posing a huge threat to human health worldwide. We aim to investigate the immune status of CD8+ T and NK cells in COVID-19 patients. METHODS: The count and immune status of lymphocytes were detected by flow cytometry in 32 COVID-19 patients and 18 healthy individuals. RESULTS: As the disease progression in COVID-19 patients, CD8+ T and NK cells were significantly decreased in absolute number but highly activated. After patients' condition improved, the count and immune status of CD8+ T and NK cells restored to some extent. GrA+CD8+ T and perforin+ NK cells had good sensitivity and specificity for assisting diagnosis of COVID-19. CONCLUSIONS: As the disease progression, the declined lymphocytes in COVID-19 patients might lead to compensatory activation of CD8+ T and NK cells. GrA+CD8+ T and perforin+ NK cells might be used as meaningful indicators for assisting diagnosis of COVID-19.

Peripheral Cytokine Levels Differ by HPV Status and Change Treatment-Dependently in Patients with Head and Neck Squamous Cell Carcinoma.

Cytokines and immune mediators play an important role in the communication between immune cells guiding their response to infectious diseases or cancer. In this study, a comprehensive longitudinal analysis of serum cytokines and immune mediators in head and neck squamous cell carcinoma (HNSCC) patients was performed. In a prospective, non-interventional, longitudinal study, blood samples from 22 HNSCC patients were taken at defined time points (TP) before, during, and every 3 months after completion of (chemo)radio)therapy (CRT/RT) until 12 months after treatment. Serum concentrations of 17 cytokines/immune mediators and High-Mobility-Group-Protein B1 (HMGB1) were measured by fluorescent bead array and ELISA. Concentrations of sFas were significantly elevated during and after CRT/RT, whereas perforin levels were significantly decreased after CRT/RT. Levels of MIP-1ß and Granzyme B differed significantly during CRT/RT by HPV status. Increased HMGB1 levels were observed at recurrence, accompanied by high levels of IL-4 and IL-10. The sFas increase and simultaneous perforin decrease may indicate an impaired immune cell function during adjuvant radiotherapy. Increased levels of pro-inflammatory cytokines in HPV+ compared to HPV- patients seem to reflect the elevated immunogenicity of HPV-positive tumors. High levels of HMGB1 and anti-inflammatory cytokines at recurrence may be interpreted as a sign of immune evasion.

Decrease of Perforin Expressing Lymphocytes after On-Pump Coronary Artery Bypass Grafting Surgery Irrespective of Carbohydrate Preoperative Oral Feeding.

BACKGROUND: Coronary artery bypass grafting (CABG) surgery continues to be the gold standard for treating the patients with coronary artery disease. CABG surgery can be performed on or off cardiopulmonary bypass, termed as on-pump or off-pump CABG, respectively. It has been shown that CABG surgery, preferably on-pump CABG surgery, leads to the changes of cell immunity during perioperative and early postoperative period. The mechanisms of regulation of the immune response in patients during and early after surgical revascularization are not fully understood. The aim of this study was to investigate the influence of carbohydrate preoperative oral feeding on frequency and perforin expression in peripheral blood lymphocytes in patients after on- or off-pump CABG surgery in early postoperative period. PATIENTS AND METHODS: In this prospective clinical study, 80 patients scheduled for CABG surgery were included in the study. The patients were randomly allocated into four groups (20 in each group): patients in Group 1 underwent on-pump CABG and did not receive carbohydrate preoperative oral feeding; patients in Group 2 underwent on-pump CABG and were preoperatively fed; patients in Group 3 underwent off-pump CABG and did not receive carbohydrate preoperative oral feeding; while patients in Group 4 underwent off-pump CABG and received carbohydrate preoperative oral feeding. Blood samples were collected immediately before (T1), 24 (T2) and 72 (T3) hours after the surgery. Peripheral blood mononuclear cells were isolated by gradient centrifugation and simultaneously labelled by antigens using fluorochrome-conjugated monoclonal antibodies. Frequency of T lymphocytes, NK and NKT cells, their subsets as well as their perforin expression were detected, and analyzed by flow cytometry. RESULTS: There was significant decrease in frequency of CD3+ and CD3+CD4+ cells, as well as perforin expressing CD3+CD8+ cells in patients who underwent on-pump CABG in comparison to patients who underwent off-pump CABG 24 hours after the surgery. Carbohydrate preoperative oral feeding did not effect changes in lymphocytes subpopulations and perforin expression at any time point. CONCLUSION: Decreases of CD3+ cells on account of CD3+CD4+ subsets, and perforin expressing cells on account of CD3+CD8+ perforin+ cells were found in patients who had undergone on-pump CABG, but not in patients who had undergone off-pump CABG surgery, irrespectively of carbohydrate preoperative oral feeding.

Interaction among smoking status, single nucleotide polymorphisms and markers of systemic inflammation in healthy individuals.

Cigarette smoke contains toxic and carcinogenic substances that contribute to the development of cancer and various diseases. Genetic variation might be important, because not all smokers develop smoking-related disease. The current study addressed the possible interactions among selected single nucleotide polymorphisms (SNPs) in genes related to systemic inflammation, smoking status, the levels of circulating immune response cells and plasma biomarkers of systemic inflammation. Sixty-four healthy blood donors were recruited, 31 of whom were current smokers and 33 were never-users of tobacco products, references. Compared to references, the smokers showed significantly increased levels of circulating total white blood cells, lymphocytes, monocytes, neutrophils, basophils and C-reactive protein (CRP). Smokers also more frequently exhibited circulating cell phenotypes that are associated with an immunocompromised state: CD8dim cells in the lymphocyte group, CD13+  CD11+ , CD13+  CD14+ , CD13+  CD56+ cells in the monocyte group and CD13+  CD11+ , CD13+  CD56+ cells in the neutrophil group. We observed an interaction among SNPs, smoking status and some of the studied biomarkers. The average plasma CRP level was significantly higher among the smokers, with the highest level found among those with the CRP rs1800947 CC genotype. Additionally, an increased CD8+  GZB+ cells in the CD8dim group were found among smokers with the GZB rs8192917 AA genotype. Thus, smoking appears to be associated with systemic inflammation and increased levels of circulating immunosuppressive cells. The extent of these effects was associated with SNPs among the smokers. This observation may contribute to a better understanding of the genetic susceptibility of smoking-related disease and the variations observed in clinical outcomes.

Cytokines are early diagnostic biomarkers of graft-versus-host disease in liver recipients.

BACKGROUND: Graft-versus-host disease (GVHD) is associated with high mortality. Early diagnosis is essential to start treatment and to improve outcomes. Because of the inflammatory nature, we hypothesis that cytokine profile of patients with GVHD may serve as diagnostic markers. The present study was to evaluate the role of cytokine profile in the diagnosis of GVHD. METHODS: An immunoassay was used to detect 29 cytokines simultaneously in the serum; the measuring sensitivity of all cytokines was pg/mL. Healthy subjects undergoing annual routine physical examinations served as negative controls; 23 patients with hepatocellular carcinoma (HCC) who had undergone liver transplantation (the LT group) comprised the test subjects. A total of 22 kidney recipients with biopsy-confirmed GVHD (the RT group) were included for comparison. HCC patients with radical surgery (the HCC group, n=22) served as positive control. The liver contents of the three cytokines, IL-2, IL-18, and IFN-gamma, were detected with immunohistochemistry. Serum granzyme B and perforin were measured by flow cytometry. RESULTS: Of the 29 cytokines, the levels of IL-2 and IL-18 were increased significantly in liver recipients with GVHD compared with healthy controls (P<0.05). The serum levels of these three cytokines in the healthy, HCC, LT, and RT groups were IL-2: 0.90+/-0.02, 4.14+/-0.61, 5.10+/-0.89, and 1.48+/-0.09 pg/mL; IL-18: 80.61+/-9.35, 109.51+/-10.93, 230.11+/-12.92, and 61.98+/-7.88 pg/mL; IFN-gamma: 24.06+/-3.88, 24.84+/-3.21, 40.37+/-5.88, and 15.33+/-4.72 pg/mL, respectively. Immunohistochemistry showed that these 3 cytokines expressions in the liver were parallel to the serum cytokine. After standard anti-GVHD treatment, the expressions of IL-2, IL-18, and IFN-gamma were decreased in the liver (P<0.05). Serum granzyme B and perforin were significantly increased in GVHD patients (P<0.05). CONCLUSIONS: IL-2, IL-18 and IFN-gamma were from liver and might serve as biomarkers for monitoring GVHD development and the effects of anti-GVHD treatment. Granzyme B and perforin may play a role in increasing IL-2, IL-18, and IFN-gamma levels in GVHD patients.

Blood cytotoxic/inflammatory mediators in non-eosinophilic asthma.

BACKGROUND: Non-eosinophilic asthma (NEA) is a distinct, often corticosteroid-resistant inflammatory asthma phenotype. NK and NKT-like cells are effector lymphocytes that we have shown, like CD28null T cells, to be relatively resistant to steroids and major sources of pro-inflammatory/cytotoxic mediators. We hypothesized that these cells and mediators would be increased in peripheral blood in NEA. METHODS: Adults with severe asthma and variable airflow obstruction, poorly controlled despite maintenance therapy with inhaled glucocorticosteroids and long-acting bronchodilators, were recruited. Blood was assessed in those with eosinophilic asthma (n = 12), NEA (n = 25) and healthy non-smoking controls (n = 30). We applied flow cytometry to measure T, CD28null, NK and NKT-like cells and their expression of granzyme B, perforin, and killer inhibitory/activating receptors CD94(Kp43), CD158b and CD107A. Intracellular pro-inflammatory cytokine production (IFN-γ and TNF-α) was assessed in 18 controls and 10 patients with asthma/group. RESULTS: In NEA, there was increased expression of granzyme B by CD8+ T cells vs. CONTROLS: There was increased expression of granzyme B and CD158 and decreased CD94 on NK cells, vs. healthy controls and those with eosinophilic asthma. IFN-γ production by NK cells and TNF-α production by NKT-like cells in NEA were significantly increased vs. CONTROLS: In both eosinophilic and NEA phenotypes, there were significant increases in CD4+28null T cells (72% and 81% increases, respectively, vs. controls) and their expression of pro-inflammatory cytokines. Significant correlations were noted between blood CD4+28null T cells and neutrophil numbers in induced sputum, and between corticosteroid dose and blood NKT-like cells, and their production of granzyme B and TNF-α and NK IFN-γ. CONCLUSION AND CLINICAL RELEVANCE: In poorly controlled asthma, altered expression of cytotoxic/pro-inflammatory mediators can be seen on a variety of lymphocyte subsets in the peripheral blood; these changes are most apparent in NEA. Whether this pattern of expression is a marker of treatment responsiveness and future risk of exacerbations remains to be determined.

Effect of the Kv1.3 voltage-gated potassium channel blocker PAP-1 on the initiation and progress of atherosclerosis in a rat model.

Acute coronary syndrome is a serious medical emergency. It occurs when an atherosclerotic plaque ruptures, leading to thrombus formation within a coronary artery. Previous studies have shown that T cells are involved in the initiation and progression of acute coronary syndrome. CD4(+)CD28(null) T lymphocytes increase in atherosclerotic plaque, and voltage-gated potassium channel Kv1.3 blockers can suppress the function of these cells in vitro by preventing exocytosis of their cytoplasmic granules. The purpose of this study was to investigate the effect of PAP-1, a small molecule voltage-gated potassium channel Kv1.3 blocker, on the development of atherosclerosis (AS) in a rat model and the potential mechanism for this effect. Plasma lipids, interferonγ, CRP, CD4(+)CD28(null) T cells, and perforin were increased and unstable atherosclerotic plaques developed in the rat model of AS. Blockade of the Kv1.3 potassium channel via PAP-1 administration decreased perforin levels and prevented plaque formation but had no effect on the other changes seen in this AS model. These findings suggest that the small molecule, voltage-gated potassium channel Kv1.3 blocker PAP-1 can suppress the development of AS in a rat model, most likely by inhibiting the exocytosis of cytoplasmic granules from CD4(+)CD28(null) T cells.

Expansion of highly differentiated cytotoxic terminally differentiated effector memory CD8+ T cells in a subset of clinically stable kidney transplant recipients: a potential marker for late graft dysfunction.

Despite the effectiveness of immunosuppressive drugs, kidney transplant recipients still face late graft dysfunction. Thus, it is necessary to identify biomarkers to detect the first pathologic events and guide therapeutic target development. Previously, we identified differences in the T-cell receptor Vß repertoire in patients with stable graft function. In this prospective study, we assessed the long-term effect of CD8(+) T-cell differentiation and function in 131 patients who had stable graft function. In 45 of 131 patients, a restriction of TCR Vß diversity was detected and associated with the expansion of terminally differentiated effector memory (TEMRA; CD45RA(+)CCR7(-)CD27(-)CD28(-)) CD8(+) T cells expressing high levels of perforin, granzyme B, and T-bet. This phenotype positively correlated with the level of CD57 and the ability of CD8(+) T cells to secrete TNF-α and IFN-γ. Finally, 47 of 131 patients experienced kidney dysfunction during the median 15-year follow-up period. Using a Cox regression model, we found a 2-fold higher risk (P=0.06) of long-term graft dysfunction in patients who had increased levels of differentiated TEMRA CD8(+) T cells at inclusion. Collectively, these results suggest that monitoring the phenotype and function of circulating CD8(+) T cells may improve the early identification of at-risk patients.

Role of CD4(+) and CD8α(+) T cells in protective immunity against Edwardsiella tarda infection of ginbuna crucian carp, Carassius auratus langsdorfii.

Edwardsiella tarda is an intracellular pathogen that causes edwardsiellosis in fish. Our previous study suggests that cell-mediated immunity (CMI) plays an essential role in protection against E. tarda infection. In the present study, we adoptively transferred T-cell subsets sensitized with E. tarda to isogenic naïve ginbuna crucian carp to determination the T-cell subsets involved in protecting fish from E. tarda infection. Recipients of CD4(+) and CD8α(+) cells acquired significant resistance to infection with E. tarda 8 days after sensitization, indicating that helper T cells and cytotoxic T lymphocytes plays crucial roles in protective immunity to E. tarda. Moreover, transfer of sensitized CD8α(+) cells up-regulated the expression of genes encoding interferon-γ (IFN-γ) and perforin, suggesting that protective immunity to E. tarda involves cell-mediated cytotoxicity and interferon-γ-mediated induction of CMI. The results establish that CMI plays a crucial role in immunity against E. tarda. These findings provide novel insights into understanding the role of CMI to intracellular pathogens of fish.

Generalized bullous fixed drug eruption is distinct from Stevens-Johnson syndrome/toxic epidermal necrolysis by immunohistopathological features.

BACKGROUND: Generalized bullous fixed drug eruption (GBFDE), a particular form of fixed drug eruption (FDE), is characterized by widespread blisters and erosions and can be confused with Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). OBJECTIVE: We sought to analyze specific features of GBFDE and differentiate it from SJS/TEN. METHODS: We retrospectively studied patients with GBFDE and SJS/TEN during a period of 10 years. GBFDE was defined as typical FDE lesions with blisters involving at least 10% body surface area on at least 3 of 6 different anatomic sites. Clinical presentations; histopathological features; immunohistochemical patterns of cluster-of-differentiation (CD)3, CD4, CD8, CD56, Fas, Fas ligand, granzyme B, perforin, granulysin, and forkhead box P3 (Foxp3); and serum granulysin levels were compared. RESULTS: Twenty-three cases of GBFDE were collected. Patients with GBFDE had shorter latent periods, less mucosal involvement, more eosinophil infiltration, and dermal melanophages. Lesional infiltrates in GBFDE had more dermal CD4(+) cells including Foxp3(+) regulatory T cells, fewer intraepidermal CD56(+) cells, and fewer intraepidermal granulysin(+) cells. The serum level of granulysin in GBFDE was also significantly lower than in SJS/TEN. LIMITATIONS: The number of cases in this study is small. CONCLUSION: GBFDE is a distinct disease distinguishable from SJS/TEN by particular features such as granulysin, CD56, and Foxp3 expressions.

Increased proportion of perforin-expressing CD8+T-cells indicates control of herpesvirus reactivation in children after stem cell transplantation.

Hematopoietic stem cell transplantation (HSCT) is frequently complicated by viral reactivations. Early diagnosis of viral reactivations and preemptive therapy relies on frequent viralload monitoring. An easy marker of effective cytotoxicity in lymphopenia is lacking and therefore we studied perforin-expression in CD8+T-cells in children following HSCT. Prospectively, we weekly monitored viral loads and perforin-expression of CD8+T-cells in whole blood by FACS, until 4months after HSCT in children. 27 patients were included (median age 4,3, range 0.3-20,1years) of whom 19 developed viral reactivations. These patients showed higher percentages of perforin-expressing CD8+T-cells (17,2%, range 0-63%) than those without (6,8%; range 0-16%) (p=0.001). The increased percentage of perforin-expressing CD8+T-cells coincided with a decrease in viral load with a median interval between maximum viral load and maximum level of perforin-expression of 0,4weeks (range 0.1-7.1). We conclude that perforin-expression in CD8+T-cells may be a marker for effective antiviral T-cell reconstitution early after HSCT in children.

Evidence for BCR-ABL-dependent dysfunctions of iNKT cells from chronic myeloid leukemia patients.

Chronic myeloid leukemia (CML) is a clonal hematopoietic stem-cell malignancy characterized by the presence of the chimeric BCR-ABL oncoprotein with deregulated tyrosine-kinase (TK) activity. Although conventional T cells are acknowledged as important players in the control of CML, a possible modification of invariant NKT (iNKT) cells, known for their antitumoral activity, has not been established as yet. Here, we showed that the expression of perforin, CD95L, and promyelocytic leukemia zinc finger, a transcription factor required for maintenance of iNKT cell functions, was reduced or suppressed in CML patients at diagnosis, as compared with healthy individuals. The proliferation rate of blood iNKT cells in response to their cognate ligand was likewise diminished. These functional deficiencies were corrected in patients having achieved complete cytogenetic remission following TK inhibitor or IFN-α therapy. iNKT cells from CML patients in the chronic phase did not display increased TK activity, which argued against a direct autonomous action of BCR-ABL. Instead, we found that their anergic status originated from both intrinsic and APC-dependent dysfunctions. Our data demonstrate that chronic phase CML is associated with functional deficiencies of iNKT cells that are restored upon remission. These results suggest a possible contribution to disease control by TK inhibitor therapies.

Assessment of different biomarkers provides valuable diagnostic standards in the evaluation of the risk of acute rejection.

Acute rejection (AR) is a strong risk factor for chronic rejection in renal transplant recipients. Accurate and timely diagnosis of AR episodes is very important for disease control and prognosis. Therefore, objectively evaluated the immune status of patients is essential in the field of post-transplantation treatment. This longitudinal study investigated the usefulness of five biomarkers, human leukocyte antigen (HLA)-G5 and sCD30 level in sera, intracellular adenosine triphosphate (iATP) release level of CD4(+) T cells, and granzyme B/perforin expression in peripheral blood mononuclear cells (PBMCs) and biopsies, to detect AR and the resolution of biomarkers in a total of 84 cases of renal transplantation. The data demonstrated that recipients with clinical or biopsy proven rejection significantly increased iATP release level of CD4(+) T cells, and elevated sCD30 but lowered HLA-G5 level in sera compared with individuals with stable graft function. Expression levels of granzyme B and perforin were also elevated in PBMCs and graft biopsies of AR patients. Taken together, we identified that upregulation of sCD30, iATP, granzyme B, perforin, and downregulation of HLA-G5 could provide valuable diagnostic standards to identify those recipients in the risk of AR. And iATP may be a better biomarker than others for predicting the graft rejection episode.

Perforin expression by CD4+ regulatory T cells increases at multiple sclerosis relapse: sex differences.

Multiple sclerosis (MS) represents the leading cause of neurological deficit among young adults, affecting women more frequently than men. In MS, the extent of central nervous system lesions is determined by the net balance between self-reactive and regulatory T-cells at any given time, among other factors, as well as by the effect of inflammatory response. Here, we studied both CD4+ and CD8+ T(Reg) in parallel in blood and CSF during MS relapse. A recruitment of both regulatory CD4+ and CD8+ T cells (T(Reg)) within the cerebrospinal fluid (CSF) takes place during MS relapse. Not previously described, the presence of CD4+ T(Reg) in CSF was higher in women than in men, which could account for the sexual dimorphism in the incidence of MS. A direct correlation between plasma oestradiol (E2) and IL-2 levels was observed, in line with a putative circuit of E2 and perforin expression by CD4+ T(Reg) playing a role in MS. Also, serum IFN-alpha was higher in females, with direct correlation with serum E2 levels. This is the first study to analyze perforin expression by CD4+ T(Reg) in MS, which was greatly enhanced in CSF, what points out a relevant role of this molecule in the suppressive effects of the CD4+ T(Reg) in MS, and contributes to the understanding of MS pathophysiology.

Different perforin expression in peripheral blood and prostate tissue in patients with benign prostatic hyperplasia and prostate cancer.

Perforin (P) is a prototypical cytotoxic molecule involved in cell-mediated immunity against various pathogens, alloantigens and particularly different tumours. The purpose of this study was to determine P expression in different lymphocyte subpopulations isolated from peripheral blood and prostate tissue of patients with benign prostatic hyperplasia (BPH) and prostate cancer (PCa) and compare it with the P expression found in the control group. Twenty subjects were recruited in each of the groups. Prostate mononuclear cells of the BPH and PCa tissues were isolated by enzymatic digestion and gradient density centrifugation, whereas peripheral blood mononuclear cells were isolated by gradient density centrifugation alone. Cells and tissue samples were labelled using monoclonal antibodies against P and different surface antigens (CD3, CD4, CD8 and CD56) and analysed by immunofluorescence and flow cytometry. Total P expression in peripheral blood lymphocytes did not differ significantly between BPH/PCa patients and control group, although the BPH and PCa tissue showed lower P expression level. A negative correlation between prostate-specific antigen levels and the overall percentage of P(+), CD3(+) CD56(-) P(+) , and CD3(-) CD56(+) P(+) cells in the prostate tissue was observed only in patients with PCa. Our findings indicate that the low frequency of P(+) lymphocytes, including T, NKT and NK cells, in the prostate tissue of patients with BPH and, particularly, PCa could be the consequence of local tissue microenvironment and one of the mechanisms involved in the pathogenesis of prostate hyperplasia following malignant alteration.

Tumor infiltrating NK cell (TINK) subsets and functional molecules in patients with breast cancer.

INTRODUCTION: NK cells have been introduced as the main innate arm of immunity against malignancies. Recent advances introduced new subsets of, and new effector molecules on NK cells suggesting new paradigms for NK cell functions in tumor immunity. Considering these new paradigms, in the current research we investigated the frequency of tumor infiltrating NK cell (TINK) subsets and their functional molecules in breast tumor tissues by flowcytometry method. METHODS: Breast tumor tissues were obtained from 32 untreated patients with breast cancer. The tissues were then minced mechanically to acquire a single cell suspension and surface-stained with monoclonal antibodies against CD3, CD56, CD11b, CD27, NKG2A, NKG2D and CXCR3. For intracellular staining (ICS), the surface-stained cells were then fixed, permeabilized and stained with anti-Perforin and anti-Granzyme B antibodies. The samples were run and the data were acquired on a four-color flowcytometer. RESULTS: The cell suspension derived from tumor tissue encompassed 3.10 ± 0.52 % CD3-CD56+(bright/dim) total NK cells. Based on the conventional classification the percentages of cytotoxic (CD3- CD56dim) and regulatory (CD3- CD56bright) NK cells were respectively 1.74 ± 0.24 % and 1.36 ± 0.48 %. According to the new classification the percentages of cytotoxic (CD3- CD56+ CD11b+ CD27-), regulatory (CD3-CD56+ CD11b+/- CD27+) and tolerant (CD3-CD56+ CD27- CD11b-) NK cells were respectively 0.48 ± 0.07, 1.55 ± 0.34 and 1.15 ± 0.51. A significant higher frequency of total NK cells (CD3-CD56+ (bright/dim)) in the breast tumor tissues of the patients whose tumor draining lymph nodes (TDLNs) has not been yet involved by tumor cells (LN- patients) compared with the ones with lymph nodes involvement (LN+) (5.91 ± 1.79 % Vs. 2.20 ± 0.20 %, P < 0.004). Furthermore, NK cells with overexpressed activating receptor; NKGD2 (CD3- CD56+(bright/dim) NKG2D+ NK cells) was observed to be elevated in LN- patients compared with the LN+ ones (70.01 ± 7.96 Vs. 42.5 ± 4.81, P < 0.011). Correlation analysis revealed the percentages of conventional regulatory NK cells (CD3- CD56bright) in breast tumor tissue to be in positive correlation with the tumor size (R = 0.380, P < 0.04). The mean percentage of this cell subset was also observed to be higher in patients with T3 tumor size compared with smaller T1 tumor size (1.61 ± 0.20 % vs. 0.75 ± 0.15 %, P < 0.023. CONCLUSION: Our observations suggest that accumulation of NK cells as well as the expression of activating NKG2D receptor by TINKs may play roles in breast tumor regression especially in the LN- patients. As the tumor growths and the size of tumor increases the accumulation of regulatory NK cells may facilitate the tumor improvement. These observations may have implications in cancer NK cell-based immunotherapy.

Serial analysis of biomarkers of acute pancreas allograft rejection.

Pancreas transplant recipients experience graft loss in spite of improvements in immunosuppressant therapies and diagnostic technologies. Therefore, a method to improve detection and management of acute rejection is needed. This longitudinal study investigated the usefulness of three biomarkers, granzyme B, perforin, and human leukocyte antigen-DR alpha (HLA-DR) measured by real-time PCR on peripheral blood mononuclear cells, for their ability to detect acute rejection and its resolution in 13 recipients of pancreas allograft. Data demonstrated that pre-transplant baseline expression of biomarkers decreased following the initiation of immunosuppression. Throughout follow-up (range 3-27 months), individuals without acute rejection episodes had little variation in their biomarker levels. Recipients with biopsy-proven rejection had a significant increase in the levels of biomarkers as early as five wk before clinical rejection diagnosis. Furthermore, all seven patients with biopsy-proven rejection demonstrated a decrease in the levels of granzyme B and perforin following the increased immunosuppression for the treatment of rejection. This is the first clinical serial measurement of biomarkers in recipients of pancreas transplants. The data demonstrate that upregulation of granzyme B, perforin, and HLA-DR in peripheral blood mononuclear cells are sensitive to changes in the immune environment and could possibly be used to identify those patients at higher risk of rejection.

A day trip to a forest park increases human natural killer activity and the expression of anti-cancer proteins in male subjects.

We previously reported that 2-night/3-day trips to forest parks enhanced human NK activity, the number of NK cells, and intracellular anti-cancer proteins in lymphocytes, and that this increased NK activity lasted for more than 7 days after the trip in both male and female subjects. In the present study, we investigated the effect of a day trip to a forest park on human NK activity in male subjects. Twelve healthy male subjects, aged 35-53 years, were selected after giving informed consent. The subjects experienced a day trip to a forest park in the suburbs of Tokyo. They walked for two hours in the morning and afternoon, respectively, in the forest park on Sunday. Blood and urine were sampled in the morning of the following day and 7 days after the trip, and the NK activity, numbers of NK and T cells, and granulysin, perforin, and granzyme A/B-expressing lymphocytes, the concentration of cortisol in blood samples, and the concentration of adrenaline in urine were measured. Similar measurements were made before the trip on a weekend day as the control. Phytoncide concentrations in the forest were measured. The day trip to the forest park significantly increased NK activity and the numbers of CD16(+) and CD56(+) NK cells, perforin, granulysin, and granzyme A/B-expressing NK cells and significantly decreased CD4(+) T cells, the concentrations of cortisol in the blood and adrenaline in urine. The increased NK activity lasted for 7 days after the trip. Phytoncides, such as isoprene, alpha-pinene, and beta-pinene, were detected in the forest air. These findings indicate that the day trip to the forest park also increased the NK activity, number of NK cells, and levels of intracellular anti-cancer proteins, and that this effect lasted for at least 7 days after the trip. Phytoncides released from trees and decreased stress hormone levels may partially contribute to the increased NK activity.

Exposure of NK cells to intravenous immunoglobulin induces IFN gamma release and degranulation but inhibits their cytotoxic activity.

The mechanisms underlying the modulation of Natural Killer (NK) cell functions by intravenous immunoglobulin (IVIg) are poorly understood. Using an ex vivo whole blood assay system we demonstrate that IVIg suppresses NK cell cytotoxicity. This was paralleled by IVIg-induced degranulation of CD56(bright), CD16(positive) NK cells, reduced expression of CD16 and elevated IFN gamma release. To assess whether these findings also occur in vivo we analyzed whole blood before and after IVIg therapy of patients. Following IVIg treatment the number of NK cells in peripheral blood dropped significantly. We observed reduced CD16 expression, elevated IFN gamma-amounts in plasma, reduced NK cell cytotoxicity, and granzyme B release into the plasma, confirming our in vitro data. These effects on the functions of NK cells describe a novel immunomodulatory effect of IVIg. The in vitro assays employed here could represent informative test systems to monitor effects of in vivo IVIg treatment at an individual level.

Effect of phytoncide from trees on human natural killer cell function.

We previously reported that the forest environment enhanced human natural killer (NK) cell activity, the number of NK cells, and intracellular anti-cancer proteins in lymphocytes, and that the increased NK activity lasted for more than 7 days after trips to forests both in male and female subjects. To explore the factors in the forest environment that activated human NK cells, in the present study we investigate the effect of essential oils from trees on human immune function in twelve healthy male subjects, age 37-60 years, who stayed at an urban hotel for 3 nights from 7.00 p.m. to 8.00 a.m. Aromatic volatile substances (phytoncides) were produced by vaporizing Chamaecyparis obtusa (hinoki cypress) stem oil with a humidifier in the hotel room during the night stay. Blood samples were taken on the last day and urine samples were analysed every day during the stay. NK activity, the percentages of NK and T cells, and granulysin, perforin, granzyme A/B-expressing lymphocytes in blood, and the concentrations of adrenaline and noradrenaline in urine were measured. Similar control measurements were made before the stay on a normal working day. The concentrations of phytoncides in the hotel room air were measured. Phytoncide exposure significantly increased NK activity and the percentages of NK, perforin, granulysin, and granzyme A/B-expressing cells, and significantly decreased the percentage of T cells, and the concentrations of adrenaline and noradrenaline in urine. Phytoncides, such as alpha-pinene and beta-pinene, were detected in the hotel room air. These findings indicate that phytoncide exposure and decreased stress hormone levels may partially contribute to increased NK activity.