Application of Immunoprofiling Using Multiplexed Immunofluorescence Staining Identifies the Prognosis of Patients with High-Grade Serous Ovarian Cancer

Immunoprofiling has an established impact on the prognosis of several cancers; however, its role and definition in high-grade serous ovarian cancer (HGSOC) are mostly unknown. This study is to investigate immunoprofiling which could be a prognostic factor in HGSOC. We produced tumor microarrays of 187 patients diagnosed with HGSOC. We performed a multiplexed immunofluorescence staining using Opal Multiplex IHC kit and quantitative analysis with Vectra-Inform system. The expression intensities of programmed death-ligand 1 (PD-L1), CD4, CD8, CD20, FoxP3, and CK in whole tumor tissues were evaluated. The enrolled patients showed general characteristics, mostly FIGO stage III/IV and responsive to chemotherapy. Each immune marker showed diverse positive densities, and each tumor sample represented its immune characteristics as an inflamed tumor or noninflamed tumor. No marker was associated with survival as a single one. Interestingly, high ratios of CD8 to FoxP3 and CD8 to PD-L1 were related to the favorable overall survival (77 vs. 39 months, 84 vs. 47 months, respectively), and CD8 to PD-L1 ratio was also a significant prognostic factor (HR 0.621, 95% CI 0.420-0.917, p = 0.017) along with well-known clinical prognostic factors. Additionally, CD8 to PD-L1 ratio was found to be higher in the chemosensitive group (p = 0.034). In conclusion, the relative expression levels of CD8, FoxP3, and PD-L1 were significantly related to the clinical outcome of patients with HGSOC, which could be a kind of significant immunoprofiling of ovarian cancer patients to apply for treatment.

Overexpression of B7-H4 is associated with infiltrating immune cells and poor prognosis in metastatic colorectal cancer

Metastasis commonly occurs in colorectal cancer (CRC) patients and confers a poor prognosis. B7-H4, an immune checkpoint molecule, has been found to be expressed in numerous tumor tissues and play critical roles in tumor progression. However, B7-H4 expression and its prognostic significance in different metastases from CRC remain unclear. In the present study, we screened a novel mouse anti-human B7-H4 monoclonal antibody (mAb) which exhibited a higher degree of recognition and sensitivity than the commercial reagent in immunohistochemistry (IHC). Using this antibody, overall 110 metastatic and paired primary lesions of CRC were analyzed for their expression of B7-H4, CD8 and CD68. Our results showed that expression of B7-H4 and CD68 in metastastic lesions was significantly higher than that in matched primary lesions (P = 0.0016, P < 0.0001). We also found a significant increase of CD68-positive immune cell infiltration in the B7-H4 high expressing metastases (P = 0.041). Moreover, upregulated B7-H4 in metastatic lesions was correlated with poor prognosis of patients (P = 0.014), while in primary lesions, B7-H4 combined with CD8 was associated with the overall survival (OS) (P = 0.043). Further, B7-H4 expression in metastatic lesions was significantly correlated with hazard ratio (HR) both in univariate and multivariate analysis. Altogether, B7-H4 in metastatic lesions is promising to be a potential prognostic indicator of CRC, and may promote tumor progression and metastasis of this cancer.

Preparation and characterization of monoclonal antibodies recognizing two CD4 isotypes of Microminipigs

Cluster of differentiation 4 (CD4) molecule expressed on the leukocytes is known to function as a co-receptor for class II major histocompatibility complex (MHC) binding to T cell receptor (TCR) on helper T cells. We previously identified two CD4 alleles (CD4.A and CD4.B) in a Microminipig population based on nucleotide sequencing and PCR detection of their gene sequences. However, CD4.B protein expression was not examined because of the unavailability of a reactive antibody to a CD4.B epitope. In this study, we have produced two swine-specific monoclonal antibodies (mAbs) against CD4.B molecules, one that recognizes only CD4.B (b1D7) and the other that recognizes both the CD4.A and CD4.B alleles (x1E10) and that can be used to distinguish CD4 T cell subsets by flow cytometry and immunohistochemistry. Using these two mAbs, we identified CD4.A and CD4.B allele-specific proteins on the surface of CD4.A (+/+) and CD4.B (+/+) T cells at a similar level of expression. Moreover, stimulation of peripheral blood mononuclear cells (PBMCs) derived from CD4.A (+/+) and CD4.B (+/+) swine with toxic shock syndrome toxin-1 (TSST-1) in vitro similarly activated both groups of cells that exhibited a slight increase in the CD4/CD8 double positive (DP) cell ratio. A large portion of the DP cells from the allelic CD4.A (+/+) and CD4.B (+/+) groups enhanced the total CD4 and class I swine leukocyte antigen (SLA) expression. The x1E10 mAb delayed and reduced the TSST-1-induced activation of CD4 T cells. Thus, CD4.B appears to be a functional protein whose expression on activated T cells is analogous to CD4.A.

Immune status is prognostic for poor survival in colorectal cancer patients and is associated with tumour hypoxia

BACKGROUND

Immunohistochemical quantification of the immune response is prognostic for colorectal cancer (CRC). Here, we evaluate the suitability of alternative immune classifiers on prognosis and assess whether they relate to biological features amenable to targeted therapy.

METHODS

Overall survival by immune (CD3, CD4, CD8, CD20 and FOXP3) and immune-checkpoint (ICOS, IDO-1 and PD-L1) biomarkers in independent CRC cohorts was evaluated. Matched mutational and transcriptomic data were interrogated to identify associated biology.

RESULTS

Determination of immune-cold tumours by combined low-density cell counts of CD3, CD4 and CD8 immunohistochemistry constituted the best prognosticator across stage II-IV CRC, particularly in patients with stage IV disease (HR 1.98 [95% CI: 1.47-2.67]). These immune-cold CRCs were associated with tumour hypoxia, confirmed using CAIX immunohistochemistry (P = 0.0009), which may mediate disease progression through common biology (KRAS mutations, CRIS-B subtype and SPP1 mRNA overexpression).

CONCLUSIONS

Given the significantly poorer survival of immune-cold CRC patients, these data illustrate that assessment of CD4-expressing cells complements low CD3 and CD8 immunohistochemical quantification in the tumour bulk, potentially facilitating immunophenotyping of patient biopsies to predict prognosis. In addition, we found immune-cold CRCs to associate with a difficult-to-treat, poor prognosis hypoxia signature, indicating that these patients may benefit from hypoxia-targeting clinical trials.

Integration of tumour infiltrating lymphocytes, programmed cell-death ligand-1, CD8 and FOXP3 in prognostic models for triple-negative breast cancer: Analysis of 244 stage I-III patients treated with standard therapy

BACKGROUND

Tumour infiltrating lymphocytes (TILs) are an established prognostic biomarker for triple-negative breast cancer (TNBC). We evaluated the role of programmed cell-death ligand-1 (PD-L1), CD8 and FOXP3 expression in refining a prognostic model for non-metastatic TNBC beyond classic factors and TILs.

METHODS

Primary tumour samples from 244 early patients with TNBC, all treated with surgery and chemotherapy, were collected. Stromal TILs were evaluated on haematoxylin-eosin slides according to guidelines. PD-L1, CD8 and FOXP3 were assessed by immunohistochemistry and evaluated by digital pathology.

RESULTS

TILs, PD-L1, CD8 and FOXP3 were positively correlated with each other (P < 0.001). TILs were confirmed as an independent prognostic factor. When PD-L1, CD8 and FOXP3 were added to multivariable models including classic factors (age, stage, histologic grade) and TILs, PD-L1 provided the largest amount of additional prognostic information: likelihood ratio χ² 4.60, P = 0.032 (in a model including classic factors and TILs 10% increments) and likelihood ratio χ² 6.50, P = 0.011 (in a model including classic factors and TILs >30% versus <30%). In the subset of patients treated with neoadjuvant chemotherapy, FOXP3 provided further prognostic information beyond classic factors, TILs and pathological complete response (pCR) (likelihood ratio χ² 5.01, P = 0.025). For patients who did not achieve a pCR, the expression of CD8 and PD-L1 was significantly increased from baseline to residual disease.

CONCLUSIONS

Beyond clinicopathological factors and TILs, other immune biomarkers may add prognostic information for early TNBC. The increased PD-L1 expression on residual disease after neoadjuvant chemotherapy strengthens the rationale of testing immune checkpoint inhibitors in the post-neoadjuvant setting.

Loss of ARPC1B impairs cytotoxic T lymphocyte maintenance and cytolytic activity

CD8 cytotoxic T lymphocytes (CTLs) rely on rapid reorganization of the branched F-actin network to drive the polarized secretion of lytic granules, initiating target cell death during the adaptive immune response. Branched F-actin is generated by the nucleation factor actin-related protein 2/3 (Arp2/3) complex. Patients with mutations in the actin-related protein complex 1B (ARPC1B) subunit of Arp2/3 show combined immunodeficiency, with symptoms of immune dysregulation, including recurrent viral infections and reduced CD8+ T cell count. Here, we show that loss of ARPC1B led to loss of CTL cytotoxicity, with the defect arising at 2 different levels. First, ARPC1B is required for lamellipodia formation, cell migration, and actin reorganization across the immune synapse. Second, we found that ARPC1B is indispensable for the maintenance of TCR, CD8, and GLUT1 membrane proteins at the plasma membrane of CTLs, as recycling via the retromer and WASH complexes was impaired in the absence of ARPC1B. Loss of TCR, CD8, and GLUT1 gave rise to defects in T cell signaling and proliferation upon antigen stimulation of ARPC1B-deficient CTLs, leading to a progressive loss of CD8+ T cells. This triggered an activation-induced immunodeficiency of CTL activity in ARPC1B-deficient patients, which could explain the susceptibility to severe and prolonged viral infections.

Immune checkpoint inhibition alters the inflammatory cell composition of human coronary artery atherosclerosis

BACKGROUND

Immune checkpoint inhibition (ICI) has emerged as a promising new approach to treat malignancy. Such therapies can result in autoimmune-related complications such as myocarditis and hepatitis. The impact of ICI on sites of preexisting chronic inflammation has been less clear. Atherosclerosis is a chronic vascular disease with a significant inflammatory component.

METHODS

To determine the effect of ICI on the inflammatory infiltrate in coronary artery atherosclerotic plaques, 11 patients who had recently been treated with ICI and subsequently underwent autopsy were matched with 11 cancer patients who had not received ICI treatment. The amount of CD3⁺ T-lymphocytes, CD8⁺ cytotoxic T-lymphocytes, and CD68⁺ macrophages and the ratios of the various cell types in the coronary artery atherosclerotic plaques were compared.

RESULTS

There was no significant difference in the absolute numbers of CD3⁺, CD8⁺, or CD68⁺ cells in the atherosclerotic plaques. In the plaques of the ICI-treated patients, there was a significant increase in the ratio of CD3⁺ cells to CD68⁺ cells (CD3/CD68) (P=.002) and a trend towards an increased CD8/CD68 ratio. The increased CD3/CD68 ratio in the ICI-treated patients resulted in 6 of the 11 patients having lymphocyte-predominate inflammation in contrast to the macrophage-predominate inflammation typically found in atherosclerotic plaques.

CONCLUSIONS

These findings indicate that ICI alters the inflammatory composition of human atherosclerotic plaque and, thus, may influence plaque progression and/or clinical coronary events.

SUMMARY

In cancer patients, treatment with immune checkpoint inhibition is associated with an altered inflammatory cell composition in coronary artery atherosclerotic plaques with an increased ratio of CD3⁺ T cells to CD68⁺ macrophages. Thus, immune checkpoint inhibition may influence plaque progression and/or clinical coronary events.

CD8β Depletion Does Not Prevent Control of Viral Replication or Protection from Challenge in Macaques Chronically Infected with a Live Attenuated Simian Immunodeficiency Virus

We evaluated the contribution of CD8αβ+ T cells to control of live-attenuated simian immunodeficiency virus (LASIV) replication during chronic infection and subsequent protection from pathogenic SIV challenge. Unlike previous reports with a CD8α-specific depleting monoclonal antibody (mAb), the CD8β-specific mAb CD8β255R1 selectively depleted CD8αβ+ T cells without also depleting non-CD8+ T cell populations that express CD8α, such as natural killer (NK) cells and γδ T cells. Following infusion with CD8β255R1, plasma viremia transiently increased coincident with declining peripheral CD8αβ+ T cells. Interestingly, plasma viremia returned to predepletion levels even when peripheral CD8αβ+ T cells did not. Although depletion of CD8αβ+ T cells in the lymph node (LN) was incomplete, frequencies of these cells were 3-fold lower (P = 0.006) in animals that received CD8β255R1 than in those that received control IgG. It is possible that these residual SIV-specific CD8αβ+ T cells may have contributed to suppression of viremia during chronic infection. We also determined whether infusion of CD8β255R1 in the LASIV-vaccinated animals increased their susceptibility to infection following intravenous challenge with pathogenic SIVmac239. We found that 7/8 animals infused with CD8β255R1, and 3/4 animals infused with the control IgG, were resistant to SIVmac239 infection. These results suggest that infusion with CD8β255R1 did not eliminate the protection afforded to LASIV vaccination. This provides a comprehensive description of the impact of CD8β255R1 infusion on the immunological composition in cynomolgus macaques, compared to an isotype-matched control IgG, while showing that the control of LASIV viremia and protection from challenge can occur even after CD8β255R1 administration.IMPORTANCE Studies of SIV-infected macaques that deplete CD8+ T cells in vivo with monoclonal antibodies have provided compelling evidence for their direct antiviral role. These studies utilized CD8α-specific mAbs that target both the major (CD8αβ+) and minor (CD8αα+) populations of CD8+ T cells but additionally deplete non-CD8+ T cell populations that express CD8α, such as NK cells and γδ T cells. In the current study, we administered the CD8β-specific depleting mAb CD8β255R1 to cynomolgus macaques chronically infected with a LASIV to selectively deplete CD8αβ+ T cells without removing CD8αα+ lymphocytes. We evaluated the impact on control of virus replication and protection from pathogenic SIVmac239 challenge. These results underscore the utility of CD8β255R1 for studying the direct contribution of CD8αβ+ T cells in various disease states.

Long-term hindlimb unloading causes a preferential reduction of medullary thymic epithelial cells expressing autoimmune regulator (Aire)

Hindlimb unloading (HU) of rodents has been used as a ground-based model of spaceflight. In this study, we investigated the detailed impact of 14-day HU on the murine thymus. Thymic mass and cell number were significantly reduced after 14 days of hindlimb unloading, which was accompanied by an increment of plasma corticosterone. Although corticosterone reportedly causes selective apoptosis of CD4+CD8+ thymocytes (CD4+CD8+DPs) in mice treated with short-term HU, the reduction of thymocyte cellularity after the 14-day HU was not selective for CD4+CD8+DPs. In addition to the thymocyte reduction, the cellularity of thymic epithelial cells (TECs) was also reduced by the 14-day HU. Flow cytometric and RNA-sequencing analysis suggested that medullary TECs (mTECs) were preferentially reduced after HU. Moreover, immunohistochemical staining suggested that the 14-day HU caused a reduction of the mTECs expressing autoimmune regulator (Aire). Our data suggested that HU impacts both thymocytes and TECs. Consequently, these data imply that thymic T cell repertoire formation could be disturbed during spaceflight-like stress.

The composition of T-cell subsets are altered in the burn wound early after injury

BACKGROUND

Burn-induced inflammation leads to impaired immune responses resulting in increased morbidity and mortality. T-cells are central in the immune response and circulating CD4 and CD8 T-cells have been used to evaluate immune status; however, the role of these T-cell subsets in the burn wound is unknown.

METHODS

Male C57BL/6 mice were subjected to a major 3rd degree scald burn or sham treatment. Twenty-four hours later, full thickness skin samples from sham mice and the burn wounds were collected and single cells were isolated and analyzed for αβ TCR, γδ TCR, CD3, CD4, CD8 and CD69 expressions by flow cytometry.

RESULTS

The burn wound contained significantly greater numbers of T-cells than skin from sham mice, due to a profound infiltration of αβ T-cells. These infiltrating αβ T-cells were primarily suppressor T-cells with a CD8+ or CD8-CD4- phenotype. The 15-fold increase in CD8+ αβ T-cells caused a decrease in the CD4:CD8 ratio from 0.7 in sham skin to 0.3 in the burn wound. In contrast, the majority of the γδ T-cells in sham skin were CD4-CD8-, which decreased 9-fold in the burn wound. CD69 expression was suppressed on burn wound αβ T-cells, but increased on γδ T-cells in the burn wound.

CONCLUSIONS

The infiltrating burn wound αβ T-cells likely act to quell inflammation. In contrast wound γδ T-cells were activated with elevated CD4 and CD69 expression. Thus, these two distinct T-cell subsets likely differentially regulate the burn wound inflammatory response.

High expression of CD8 predicts favorable prognosis in patients with lung adenocarcinoma: A cohort study

Lung carcinoma is the most common cause of malignant death worldwide. CD8 T cells, as critical elements in antitumor immunity, could function as good prognostic indicators in various kinds of cancers such as renal cell carcinoma and colorectal cancer, but its prognostic role in lung adenocarcinoma is still unclear. The objective of this study was to explore the prognostic role of CD8 expression in lung adenocarcinoma.Paired tumor and adjacent noncancerous tissues were obtained from 102 patients with lung adenocarcinoma, and CD8 expression of these samples was examined by immunohistochemistry. We evaluated the relationships between the expression of CD8 and pathological grade, TNM stage, clinical stage, as well as overall survival (OS).Expression of CD8 was significantly increased in lung adenocarcinoma compared with that in adjacent lung adenocarcinoma (P < .001). CD8 expression was negatively correlated with pathological grade (r = -0.216, P = .022) and N stage (r = -0.372, P < .001), while no statistical correlation with T stage, or clinical stage. Importantly, OS was numerically increased in patients with high expression of CD8 than the group of intermediate and low CD8 expression (P = .12). Furthermore, CD8 could significantly increase OS (P = .043, HR: .713, 95%CI: .515-.989) by univariate Cox's proportional hazards regression analysis.Our data indicated that expression of CD8, as a protective factor, is correlated with the outcome of patients with lung adenocarcinoma. Furthermore, CD8 might be a novel prognostic biological marker for patients with lung adenocarcinoma.

Characterization of circulating CD4+ CD8+ double positive and CD4- CD8- double negative T-lymphocyte in children with β-thalassemia major

Infectious complications represent the second most common cause of mortality and a major cause of morbidity in β-thalassemia major (BTM), with a prevalence of 12-13%. The data on unconventional T-lymphocyte subsets in BTM children are limited. The aim of the present study was to investigate and evaluate phenotypic alterations in CD4⁺CD8⁺ double positive (DP), CD4^- CD8^- double negative (DN), and natural killer T-lymphocytes (NKT) in BTM children in comparison to healthy controls. Our case control study included 80 children with BTM and 40 healthy children as controls. Assessment of unconventional T-lymphocyte populations was done using sensitive four-color flow cytometry (FACSCalibur). Our analysis of the data showed a significantly higher frequency CD4⁺ CD8⁺ (double-positive) T cells, CD4^- CD8^- (double negative) T cells, and natural killer T cells in the peripheral blood of both BTM groups (splenectomized and non-splenectomized) as compared to healthy controls, suggesting that these cells may play a role in the clinical course of BTM. The relationship of the unconventional T-lymphocytes to immune disorders in BTM children remains to be determined. Further longitudinal study with a larger sample size is warranted to elucidate the role these cells in BTM.

UMIN-CTR STUDY DESIGN

TRIAL NUMBER: UMIN000018950.

Low dose Cyclosporin A treatment increases live birth rate of unexplained recurrent abortion - initial cohort study

BACKGROUND AND OBJECTIVE

Pregnancy is similar to allogeneic transplantation. Eighty percent of unexplained recurrent spontaneous abortions (URSA) relate to disturbances of immune regulation. Cyclosporin A (CsA) is a immunosuppressant widely used after organ transplantation and to treat autoimmune disease. Animal studies show that low dose of CsA could induce maternal-fetal immunity tolerance while enhance trophoblast invasion. So far no clinical trial reported on the effect and safety of cyclosporin A treatment for URSA has been published. The objective of this study was to explore the effect, safety, and mechanism of low-dose CsA treatment in human patients in order to find a novel therapy to treat URSA.

MATERIALS AND METHODS

Eighty-six patients with eligible URSA treated at the clinic of the present hospital were included in this study from December 2009 to December 2012. The research was approved by the Ethics committee. Through a clinical study with prospective non-randomized controlled trials, the patients were divided into CsA treatment group (n = 66 cases) and in control group (n = 20 cases) based on the patients' choice. Both groups started treatment as soon as the pregnancy test was positive. Patients in the treatment group were treated with oral CsA 100 mg/day for 30 days. Patients in the control group were treated with progesterone 20 mg im per day until 12 weeks of gestation. Cytoimmunology test of CD3, CD4, CD8, CD4/8, CD4/25, CD19/21, and Th/Ts were examined before and after the treatment in both groups. Clinical consequences of mothers and fetuses were followed up and recorded. Live birth rate and cytoimmunology markers and their change before and after the treatment were analyzed and compared between the two groups.

RESULTS

The live birth rate was significantly higher in study group (41/66, 62.1%) than in the control group (6/20, 30.0%) (p < 0.001). There was no obvious side effect and adverse consequence in the pregnancy women. No IUGR or birth defect was observed in fetus in this study. After CsA treatment, CD3 level in maternal blood was higher in successful group than abortion group but CD8 level was decreased after CsA treatment.

CONCLUSIONS

Low-dose CsA treatment increases live birth rate of unexplained recurrent abortion. No maternal-fetal adverse consequence was observed in this study and it is safe in clinic use. The mechanism of CsA therapy may be related to immune regulation which may favor the success of pregnancy.

Diethylstilbestrol (DES)-Induced Fetal Thymic Atrophy in C57BL/6 Mice: Inhibited Thymocyte Differentiation and Increased Apoptotic Cell Death

Treatment of pregnant C57Bl/6 mice with 48 μg/kg diethylstilbestrol (DES) on gestation days (GDs) 14 and 16 resulted in both decreased day 18 fetal thymic cellularity as well as alterations in thymocyte phenotype. Histopathologic examination of GD 18 fetal thymi from DES-exposed dams demonstrated a decrease in thymic size and cellularity and an increase in pyknotic nuclei, indicative of apoptosis, relative to control thymi. Thymic architecture was also altered by DES treatment with a decrease in the distinction between the cortical and medullary regions. Flow cytometric staining of day 18 thymocyte suspensions with the apoptotic marker 7-aminoactinomycin D showed a decrease in thymocyte viability after DES, and a concomitant increase of thymocytes in early apoptosis. When thymocytes were co-identified by CD4 and CD8 cell surface antigen expression, trends toward increased apoptosis were present in the CD4+CD8+and CD4+CD8−subpopulations, and significantly increased apoptosis occurred in the CD4−CD8−and CD4−CD8+subpopulations. These histopathologic and flow cytometric findings support enhanced apoptosis of thymocytes as a contributing factor to fetal thymic atrophy caused by DES.

Histopathological and Immunohistochemical Analysis of Small Intestinal Biopsies in Adults Suspected of Celiac Disease

OBJECTIVE

To analyse histomorphological and immunohistochemical analysis of small intestinal biopsies in adults suspected of celiac disease.

STUDY DESIGN

Descriptive study.

PLACE AND DURATION OF STUDY

Department of Histopathology, Army Medical College, Rawalpindi, from November 2014 to December 2015.

METHODOLOGY

Fifty cases of small intestinal mucosal biopsies (duodenal and jejunal) were analysed in adult patients aged above 14 years suspected of celiac disease. Their histomorphological data was recorded using Modified Marsh Criteria. Type of intraepithelial lymphocytes was assessed using immunohistochemistry. Intraepithelial lymphocytes were counted both by H&E stain and immunostain CD3 and CD20.

RESULTS

Thirty-four percent patients were aged between 21 - 30 years and 22% patients aged between 41 - 50 years. There were 84% (n=42) males. Thirteen (26%) cases showed focal villous atrophy, 32 (64%) cases showed partial villous atrophy and 5 (10%) cases showed complete villous atrophy. Anti-tissue transglutaminase antibody was positive in 21 (42%) cases. CD3 immunomarker was positive for intraepithelial lymphocytes in all 50 cases while CD20 immunomarker showed focal positivity in areas with lymphoid follicle formation. The count of intraepithelial lymphocytes was found to be almost equal (with a difference of 3 - 4 lymphocytes) on both H&E stain and immunostain CD3 and CD20.

CONCLUSION

Males aged 21 - 30 years were the most commonly affected group. The most frequent change in histology was partial villous atrophy along with lymphocytic enteritis. All the intraepithelial lymphocytes were present in crescendo pattern of distribution.

Expansion of highly activated invariant natural killer T cells with altered phenotype in acute dengue infection

Invariant natural killer T (iNKT) cells are capable of rapid activation and production of cytokines upon recognition of antigenic lipids presented by CD1d molecules. They have been shown to play a significant role in many viral infections and were observed to be highly activated in patients with acute dengue infection. In order to characterize further their role in dengue infection, we investigated the proportion of iNKT cells and their phenotype in adult patients with acute dengue infection. The functionality of iNKT cells in patients was investigated by both interferon (IFN)-γ and interleukin (IL)-4 ex-vivo enzyme-linked immunospot (ELISPOT) assays following stimulation with alpha-galactosyl-ceramide (αGalCer). We found that circulating iNKT cell proportions were significantly higher (P = 0·03) in patients with acute dengue when compared to healthy individuals and were predominantly of the CD4(+) subset. iNKT cells of patients with acute dengue had reduced proportions expressing CD8α and CD161 when compared to healthy individuals. The iNKT cells of patients were highly activated and iNKT activation correlated significantly with dengue virus-specific immunoglobulin (Ig)G antibody levels. iNKT cells expressing Bcl-6 (P = 0·0003) and both Bcl-6 and inducible T cell co-stimulator (ICOS) (P = 0·006) were increased significantly in patients when compared to healthy individuals. Therefore, our data suggest that in acute dengue infection there is an expansion of highly activated CD4(+) iNKT cells, with reduced expression of CD161 markers.

Overexpression of CD39 and high tumoral CD39⁺/CD8⁺ ratio are associated with adverse prognosis in resectable gastric cancer

CD39/ectonucleoside triphosphate diphosphohydrolase-1 (ENTPD1) is a cell surface-located, rate-limiting enzyme in the generation of adenosine, and plays a crucial role in tumor development. We examined co-expression of CD39 and CD8in gastric cancer (GC) and showed that the expression of CD39 and CD8 increased significantly in tumor tissues compared to paired peritumor tissues. The expression of tumoral CD39 (tCD39), but not tumoral CD8 (tCD8), was related to overall survival. Furthermore, the CD39(+)/CD8(+) ratio was associated with poor prognosis in resected GC patients. Taken together, our data indicate that highCD39 expression and high tCD39(+)/CD8(+) ratio in GC is a predictor of poor prognosis for GC patients after radical resection. Moreover, CD39 could serve as a potential target for cancer immunotherapy.

Stress-associated erythropoiesis initiation is regulated by type 1 conventional dendritic cells

Erythropoiesis is an important response to certain types of stress, including hypoxia, hemorrhage, bone marrow suppression, and anemia, that result in inadequate tissue oxygenation. This stress-induced erythropoiesis is distinct from basal red blood cell generation; however, neither the cellular nor the molecular factors that regulate this process are fully understood. Here, we report that type 1 conventional dendritic cells (cDC1s), which are defined by expression of CD8α in the mouse and XCR1 and CLEC9 in humans, are critical for induction of erythropoiesis in response to stress. Specifically, using murine models, we determined that engagement of a stress sensor, CD24, on cDC1s upregulates expression of the Kit ligand stem cell factor on these cells. The increased expression of stem cell factor resulted in Kit-mediated proliferative expansion of early erythroid progenitors and, ultimately, transient reticulocytosis in the circulation. Moreover, this stress response was triggered in part by alarmin recognition and was blunted in CD24 sensor- and CD8α+ DC-deficient animals. The contribution of the cDC1 subset to the initiation of stress erythropoiesis was distinct from the well-recognized role of macrophages in supporting late erythroid maturation. Together, these findings offer insight into the mechanism of stress erythropoiesis and into disorders of erythrocyte generation associated with stress.

Interferon-gamma Inhibits Melanogenesis and Induces Apoptosis in Melanocytes: A Pivotal Role of CD8+ Cytotoxic T Lymphocytes in Vitiligo

Increased expression of the cytokine interferon (IFN)-γ plays a pivotal role in vitiligo-induced depigmentation. However, the major source of IFN-γ in vitiligo patients and the mechanisms underlying melanocyte destruction are unknown. In this study, a large number of skin infiltrating IFN-γ+ cells and CD8+ T cells were detected in progressive vitiligo. Among the peripheral blood mononuclear cells (PBMCs) of vitiligo patients, CD8+ cytotoxic T lymphocytes (CTLs) that express IFN-γ exhibited significant expansion, which suggests that activated CTLs are the main source of increased IFN-γ in progressive vitiligo. An in vitro analysis demonstrated that IFN-γ inhibits melanogenesis in primary cultured human melanocytes by altering melanogenic enzyme mRNA expression and, more importantly, that IFN-γ directly induces melanocyte apoptosis. Our data indicate that vitiligo pathophysiology may be linked to globally activated CD8+ CTL subpopulations, which produce increased IFN-γ and induce melanocyte dysfunction and apoptosis.

CD8 and CD45RO T lymphocytes in bone marrow of gastric cancer patients: correlation with disseminated tumor cells and disease outcome

AIM

To evaluate the association between the presence of CD8 and CD45RO T lymphocytes in bone marrow (BM), disseminated tumor cells (DTCs), tumor hypoxia and their impact on disease outcome.

MATERIAL AND METHODS

91 naïve gastric cancer (GC) patients were enrolled into the study. DTCs, CD8- and CD45RO-positive T lymphocytes in BM were detected using immunocytochemistry. All patients were thoroughly informed about the study that was approved by the local ethics committee. Statistical analyses were done using NCSS2000/PASS2000 and Prism, version 4.03 software packages.

RESULTS

It was detected that 80.5 and 81.3% of patients had CD8- and CD45RO-positive T cells in BM, respectively. When DTCs were detected in BM, the number of patients with CD8-and CD45RO-positive T cells in BM were 86.1 and 84.4%, respectively. It was also determined that the number of patients with DTCs in BM with categories M0 and M1 and with CD8- and CD45RO-positive T cells in BM were 86.2 and 85.7%, 85.7 and 80.0%, respectively. The association between DTCs in BM and presence of CD8 and CD45RO T cells lymphocytes in BM was not found. At the same time it was shown the association between presence of CD8 and CD45RO T lymphocytes and survival. The presence of CD8- and CD45RO-positive T cells in BM were accompanied with significantly longer overall survival of patients compared to that of patients without CD8- and CD45RO-positive T cells in BM.

CONCLUSION

Patients with the presence of CD8- and CD45RO-positive T cells in BM demonstrated better survival of GC patients than those with the absence of these cells in BM. It may be suggested that tumor cells in BM are controlled in a dormant state by T cells in BM, in particular by CD8-positive T cells.

In vitro and in vivo evaluation of 2-chloroethylnitrosourea derivatives as antitumor agents

AIM

To evaluate potential of Naphthal-NU, Napro-NU and 5-Nitro-naphthal-NU, 2-chloroethylnitrosourea compounds with substituted naphthalimide in the pre-clinical studies.

MATERIALS AND METHODS

In vitro cytotoxicity of three nitrosoureas was determined in human and mouse tumor cell lines by MTT assays. In vivo anti-tumor potential was evaluated in Sarcoma-180 (S-180) and Ehrlich's carcinoma (EC) solid tumors. Apoptosis in S-180 cells was analyzed by using Annexin V-Propidium Iodide (PI). Histological analysis of liver and kidney was performed at optimum dose (50 mg/kg). Expression status of CD4(+), CD8(+) and CD25(+) cells in treated mouse were also examined.

RESULTS

Significant tumor growth retardation by the compounds was noted in early and advanced disease groups, as the life span of drug treated mice increased considerably. Drug induced killing was observed by induction of apoptosis. Naphthal-NU and 5-Nitro-naphthal-NU were effective to normalize the tumor induced structural abnormalities of liver and kidney. The compounds have no immunotoxic effect on CD4(+) and CD8(+) T cells and down regulate CD4(+)CD25(+) regulatory T cells.

CONCLUSION

Overall data holds promise for the antitumor activity with lower toxicity of the compounds that can be utilized for the treatment of human malignant tumors.

Peripheral blood lymphocyte phenotype of ZAP-70⁺ and ZAP-70⁻ patients with B-cell chronic lymphocytic leukaemia

BACKGROUND

Up to now, the immune status of chronic lymphocytic leukemia (CLL) patients in association with the expression of zeta-chain-associated protein kinase 70 (ZAP-70) in leukemic cells has not been evaluated.

AIM

The aim of this work was the study of the peripheral blood (PB) T-lymphocyte phenotypes in ZAP-70-positive (ZAP-70(+)) and ZAP-70-negative (ZAP-70(-)) untreated patients with CLL.

MATERIALS AND METHODS

ZAP-70-, CD25-, CD3-, CD4-, and CD8-positive lymphocytes were enumerated by flow cytometry in PB of 120 untreated CLL patients. CD8+, CD3+CD4+ and CD3+CD25+ cells were counted for the non-leukemic lymphocytes.

RESULTS

The patients were distributed into two groups: the ZAP-70(+) group of high CLL progression (n = 61), and the ZAP-70(-) group of low CLL progression (n = 59). In the ZAP-70(+) group, the ratio CD4/CD8 (0.33 ± 0.62; p = 0.001) and the numbers of the CD3+ (34.8 ± 8.1%; p = 0.01), CD3+CD4+ (24.4% ± 4.8; p = 0.001), and CD3+CD25+ (6.2 ± 0.91%; p = 0.001) lymphocytes were reduced and the percentage of the CD8+ cells (73.1 ± 4.6%; p = 0.0001) was above the norm. In the ZAP-70(-) group, the number of the CD3+CD4+ cells (36.9 ± 6.1%; p = 0.001) was within the norm, but the numbers of the CD8+ (11.3 ± 1.1%; p = 0.0001) and CD3+ (41.2 ± 5.3%; p = 0.05) lymphocytes were reduced; the ratio CD4/CD8 (3.26 ± 0.88; p = 0.001) and the percentage of the CD3+CD25+ cells (27.1 ± 3.4%; p = 0.0001) were above the norm.

CONCLUSIONS

Our data show that the increased CD4/CD8 ratio, caused by the reduced number of the CD8+ lymphocytes, and the increased number of CD3+CD25+ cells are characteristic for the ZAP-70(-) group (slow progressing) of untreated CLL patients. In ZAP-70(+) patients, the CD4/CD8 ratio was significantly below the norm indicating an active disease process. Results of our study contribute to identification of CLL patients with different prognosis in routine diagnostic/prognostic procedures.

The role of intrahepatic CD3+/CD4-/CD8- double negative T (DN T) cells in enhanced acetaminophen toxicity

The role of the immune system, specifically NK, NKT and CD3 cells, in acetaminophen (APAP) induced liver injury remains inconsistently defined. In the present study, wild type (C57BL/6J) mice and granzyme B deficient (GrB -/-) mice were treated with acetaminophen to assess the role of the immune system in acute liver injury. Doses of acetaminophen that induced sub lethal liver injury in wild type mice unexpectedly produced fatal hepatotoxicity in granzyme B deficient (GrB -/-) mice. Analysis revealed that GrB -/- mice had an increased population of intrahepatic CD3 (+), CD4 (-), and CD8 (-) lymphocytes expressing the CD69 activation marker and Fas ligand. Depletion of these cells in the GrB -/- and wild type mice made them less susceptible to APAP injury, while depletion of NK1.1 (+) cells or both CD4 (+) and CD8 (+) T cells failed to provide the same hepatoprotection. Transfer of the GrB -/- IHLs further exacerbated liver injury and increased mortality in wild type mice but not in LRP/LPR mice, lacking fas expression.

CONCLUSIONS

Acetaminophen toxicity is enhanced by the presence of activated, FasL expressing intrahepatic CD3 (+), CD4 (-), CD8 (-), NK1.1 (-) T cells. Depletion of these cells from GrB -/- mice and wild type mice greatly reduces mortality and improves the course of liver injury recovery.

Dissecting the regulatory microenvironment of a large animal model of non-Hodgkin lymphoma: evidence of a negative prognostic impact of FOXP3+ T cells in canine B cell lymphoma

The cancer microenvironment plays a pivotal role in oncogenesis, containing a number of regulatory cells that attenuate the anti-neoplastic immune response. While the negative prognostic impact of regulatory T cells (Tregs) in the context of most solid tissue tumors is well established, their role in lymphoid malignancies remains unclear. T cells expressing FOXP3 and Helios were documented in the fine needle aspirates of affected lymph nodes of dogs with spontaneous multicentric B cell lymphoma (BCL), proposed to be a model for human non-Hodgkin lymphoma. Multivariable analysis revealed that the frequency of lymph node FOXP3⁺ T cells was an independent negative prognostic factor, impacting both progression-free survival (hazard ratio 1.10; p = 0.01) and overall survival (hazard ratio 1.61; p = 0.01) when comparing dogs showing higher than the median FOXP3 expression with those showing the median value of FOXP3 expression or less. Taken together, these data suggest the existence of a population of Tregs operational in canine multicentric BCL that resembles thymic Tregs, which we speculate are co-opted by the tumor from the periphery. We suggest that canine multicentric BCL represents a robust large animal model of human diffuse large BCL, showing clinical, cytological and immunophenotypic similarities with the disease in man, allowing comparative studies of immunoregulatory mechanisms.

ASSOCIATION OF TEMPORAL LOBE INFLAMMATORY LEUKOENCEPHALOPATHY WITH TWO B CELL MALIGNANCIES

Identification of etiological connections among virtually distinct diseases in a patient may be sometimes challenging. We report a unique case with two B cell malignancies and an inflammatory leukoencephalopathy. Three days prior to admission, the elderly male patient developed fatigue, headaches, recurrent vomiting, memory disturbances, depression and somnolence. Clinical, laboratory and imaging evaluations as well as post mortem histological studies were performed. Simultaneous presence of primary central nervous system B cell lymphoma, temporal lobe inflammatory leukoencephalopathy and multiple (smoldering) myeloma, was revealed by the detailed work up in the treatment-naïve patient. Based on recent data from genomic studies, we propose that a sequential evolution of molecular pathology lead to the co-occurrence of multiple myeloma and primary central nervous system B cell lymphoma in this patient, and interpret the development of the temporal lobe leukoencephalopathy as a likely paraneoplastic complication of smoldering myeloma.

IL-7-Dependent Homeostatic Proliferation in the Presence of a Large Number of T Cells inGldMice

In gld mice, CD4 and 8-double-negative (DN) T cells as well as naive and memory-phenotype T cells accumulate in the peripheral lymphoid organs. Although Fas ligand (L) defect accounts for the progressive accumulation of abnormal DN T cells, the existence of other mechanisms which may be involved in the defective homeostasis in gld mice has been unclear. In this study, we analyze T-cell homeostasis in gld mice using adoptive transfer systems. It was shown that a gld, but not C57BL/6 (B6), environment led to augmented proliferation of B6 T cells transferred without up-regulation of CD69. Thus, the augmented T-cell proliferation seemed to result from mal-homeostatic proliferation even in the presence of a large number of recipient T cells. T cells from lpr mice showed no significant proliferation in the B6 environment, suggesting that the absence of Fas-Fas L interaction was not responsible for the mal-homeostatic proliferation. Although similar levels of IL-7 mRNA were detected in gld and B6 spleens, the intensity of CD127 and the proportion of CD127+ cells in the T cells were significantly lower in gld mice than in B6 mice, suggesting that IL-7 excess in a gld environment is responsible for the abnormal proliferation of transferred T cells. The administration of anti-CD127 antibody inhibited the proliferation of transferred lymphocytes. Thus, IL-7-dependent proliferation seems to be involved in the abnormal proliferation of lymphocytes in gld recipients.

Tumor immune subtypes distinguish tumor subclasses with clinical implications in breast cancer patients

There is strong evidence that the host's cellular immune response is linked to tumor progression, however its impact on patient outcome in breast cancer is poorly understood. The purpose of this study is to define tumor immune subtypes, focusing on cellular immune responses and investigate their prognostic effect in breast cancer patients. Our training (n = 440) and validation cohort (n = 382) consisted of all early breast cancer patients primarily treated with surgery in our center between 1985 and 1996. Tumor tissue sections were immunohistochemically stained for CD8 (CTL) and PEN5 (NK cells). Tumor expression of classical and non-classical human leukocyte antigen class I, and tumor-infiltrating Tregs were previously determined. Tumor immune subtypes were constructed based on quantification of these markers and biological rationale. High, intermediate, and low immune susceptible tumor immune subtypes were found, respectively, in 16, 63, and 20 % of patients in the training cohort and 16, 71, and 13 % in the validation cohort. The subtypes showed to be statistically significant prognostic in multivariate analyses for relapse free period (RFP) [p < 0.0001, intermediate versus high: hazard ratio (HR) 1.95; low versus high HR 2.98] and relative survival (RS) (p = 0.006, intermediate versus high HR 3.84; low versus high: HR 4.26). Validation of these outcome analyses confirmed the independent prognostic associations: RFP (p = 0.025) and RS (p = 0.040). The tumor immune subtypes that we present represent a prognostic profile with solid underlying biological rationale and with high discriminative power confirmed in an independent validation cohort. Our results emphasize the importance of tumor immune surveillance in the control of tumor development and, therefore, in determining patient prognosis. Tumor immune subtype profiling is promising for prognosis prediction and the achievement of tailored treatment for breast cancer patients.

Immune response in cervical lymph nodes from patients with primary oral squamous cell carcinoma

BACKGROUND

Deficient immune response in the cervical lymph nodes of patients with head and neck squamous cell carcinoma may contribute to dissemination of metastatic neoplastic cells. This study evaluates the immune response in cervical lymph nodes from patients with primary oral cavity squamous cell carcinoma (OCSCC).

METHODS

The density of immature (CD1a(+)) and mature (CD83(+)) dendritic cells (DCs), cytotoxic T lymphocytes CD8(+) /perforin(+) (CTLs), and Foxp3(+) regulatory T (Tregs) cells in the lymph nodes of patients with OCSCC without cervical lymph node metastases (LN1) (negative) (n = 10) were identified through immunohistochemistry. From patients with cervical lymph node metastases, samples were obtained of lymph nodes both with (LM2) (positive) (n = 10) and without (LN2) (negative) (n = 10) metastases.

RESULTS

The results demonstrated that the number of CD1a(+) and Foxp3(+) cells was significantly higher in the LM2 group than in either the LN1 or the LN2 group. In addition, the number of CD8(+) /perforin(+) and CD83(+) cells was significantly lower in the LM2 group than in the other groups.

CONCLUSION

The results of this study demonstrate a higher density of immature DCs and Tregs cells and a lower density of mature DCs and activated CTLs in metastatic than in non-metastatic lymph nodes. These findings might indicate an immunosuppressive microenvironment, which could be involved in the spread of neoplastic cells to cervical lymph nodes.

Prevention of soya-induced enteritis in Atlantic salmon (Salmo salar) by bacteria grown on natural gas is dose dependent and related to epithelial MHC II reactivity and CD8α+ intraepithelial lymphocytes

An experiment was carried out to study the preventive effect of bacterial meal (BM) produced from natural gas against plant-induced enteropathy in Atlantic salmon (Salmo salar). Salmon were fed a diet based on fish meal (FM) or seven diets with 200 g/kg solvent-extracted soyabean meal (SBM) to induce enteritis in combination with increasing levels of BM from 0 to 300 g/kg. Salmon fed a SBM-containing diet without BM developed typical SBM-induced enteritis. The enteritis gradually disappeared with increasing inclusion of BM. By morphometry, no significant (P>0.05) differences in the size of stretches stained for proliferating cell nuclear antigen were found with 150 g/kg BM compared with the FM diet. Increasing BM inclusion caused a gradual decline in the number of cluster of differentiation 8 α positive (CD8α+) intraepithelial lymphocytes, and fish fed BM at 200 g/kg or higher revealed no significant difference from the FM diet. Histological sections stained with antibody for MHC class II (MHC II) showed that fish with intestinal inflammation had more MHC II-reactive cells in the lamina propria and submucosa, but less in the epithelium and brush border, compared with fish without inflammation. There were no significant (P>0.05) differences in growth among the diets, but the highest levels of BM slightly reduced protein digestibility and increased the weight of the distal intestine. In conclusion, the prevention of SBM-induced enteritis by BM is dose dependent and related to intestinal levels of MHC II- and CD8α-reactive cells.

The dominant human conjunctival epithelial CD8αβ+ T cell population is maintained with age but the number of CD4+ T cells increases

The conjunctiva is a highly specialized ocular mucosal surface that, like other mucosa, houses a number of leukocyte populations. These leukocytes have been implicated in age-related inflammatory diseases such as dry-eye, but their phenotypic characteristics remain largely undetermined. Existing literature provides rudimentary data from predominantly immunohistochemical analyses of tissue sections, prohibiting detailed and longitudinal examination of these cells in health and disease. Using recovered cells from ocular surface impression cytology and flow cytometry, we examined the frequency of leukocyte subsets in human conjunctival epithelium and how this alters with age. Of the total CD45+ leukocyte population within the conjunctival epithelium, 87% [32-99] (median) [range] comprised lymphocytes, with 69% [47-90] identified as CD3 + CD56- T cells. In contrast to peripheral blood, the dominant conjunctival epithelial population was TCRαβ + CD8αβ + (80% [37-100]) with only 10% [0-56%] CD4+ cells. Whilst a significant increase in the CD4+ population was seen with age (r = 0.5; p < 0.01) the CD8+ population remained unchanged, resulting in an increase in the CD4:CD8 ratio (r = 0.5;p < 0.01). IFNγ expression was detectable in 18% [14-48] of conjunctival CD4+ T cells and this was significantly higher among older individuals (<35 years, 7[4-39] vs. >65 years, 43[20-145]; p < 0.05). The elevation of CD4+ cells highlights a potentially important age-related alteration in the conjunctival intra-epithelial leukocyte population, which may account for the vulnerability of the aging ocular surface to disease.

GB virus C viremia is associated with higher levels of double-negative T cells and lower T-cell activation in HIV-infected individuals receiving antiretroviral therapy

Double-negative T cells (DNTCs; ie, CD3(+)CD4(-)CD8(-) T cells) play a role in limiting chronic immune activation. GB virus C (GBV-C) infection is associated with reduced T-cell activation in human immunodeficiency virus (HIV)-infected individuals. T-cell activation and DNTCs were measured in HIV-infected subjects with a nondetectable HIV load. GBV-C-viremic subjects had significantly reduced CD4(+) and CD8(+) T-cell activation (P = .003 and .034, respectively) and significantly increased DNTCs (P = .038), compared with nonviremic subjects. GBV-C load correlated with DNTC percentage (P = .004). Thus, GBV-C infection is associated with an increase in DNTCs, which may contribute to reduced immune activation during HIV infection.

Tumor-infiltrating lymphocytes predict response to chemotherapy in patients with advance non-small cell lung cancer

Accumulating preclinical evidence suggests that anticancer immune responses contribute to the success of chemotherapy. The predictive significance of tumor-infiltrating lymphocytes (TILs) for response to neoadjuvant chemotherapy in non-small cell lung cancer (NSCLC) remains unknown. The aim of this study was to investigate the prognostic and predictive value of TIL subtypes in patients with advanced NSCLC treated with platinum-based chemotherapy. In total, 159 patients with stage III and IV NSCLC were retrospectively enrolled. The prevalence of CD3(+), CD4(+), CD8(+) and Foxp3(+) TILs was assessed by immunohistochemistry in tumor tissue obtained before chemotherapy. The density of TILs subgroups was treated as dichotomous variables using the median values as cutoff. Survival curves were estimated by the Kaplan-Meier method, and differences in overall survival between groups were determined using the Log-rank test. Prognostic effects of TIL subsets density were evaluated by Cox regression analysis. The presence of CD3(+), CD4(+), CD8(+), and FOXP3(+) TILs was not correlated with any clinicopathological features. Neither the prevalence of TILs nor combined analysis displayed obvious prognostic performances for overall survival in Cox regression model. Instead, higher FOXP3(+)/CD8(+) ratio in tumor sites was an independent factor for poor response to platinum-based chemotherapy in overall cohort. These findings suggest that immunological CD8(+) and FOXP3(+)Tregs cell infiltrate within tumor environment is predictive of response to platinum-based neoadjuvant chemotherapy in advanced NSCLC patients. The understanding of the clinical relevance of the microenvironmental immunological milieu might provide an important clue for the design of novel strategies in cancer immunotherapy.

Cell-type-specific expression of STAT transcription factors in tissue samples from patients with lymphocytic thyroiditis

Expression of cytokine-regulated signal transducer and activator of transcription (STAT) proteins was histochemically assessed in patients diagnosed as having Hashimoto's disease or focal lymphocytic thyroiditis (n = 10). All surgical specimens showed histological features of lymphocytic thyroiditis, including a diffuse infiltration with mononuclear cells and an incomplete loss of thyroid follicles, resulting in the destruction of glandular tissue architecture. Immunohistochemical analysis demonstrated differential expression patterns of the various members of the STAT transcription factors examined, indicating that each member of this conserved protein family has its distinct functions in the development of the disease. Using an antibody that specifically recognized the phosphorylated tyrosine residue in position 701, we detected activated STAT1 dimers in numerous germinal macrophages and infiltrating lymphocytes as well as in oncocytes. In contrast, STAT3 expression was restricted to epithelial cells and showed a clear colocalization with the antiapoptotic protein Bcl-2. Moreover, expression of phospho-STAT3 was associated with low levels of stromal fibrosis, suggesting that STAT3 serves as a protective factor in the remodeling of the inflamed thyroid gland. Phospho-STAT5 immunoreactivity was detected in numerous infiltrating cells of hematopoietic origin and, additionally, in hyperplastic follicular epithelia. This tissue distribution demonstrated that activated STAT5 molecules participate in both lymphocytopoiesis and possibly also in the buildup of regenerating thyroid follicles. Taken together, the cell-type-specific expression patterns of STAT proteins in human lymphocytic thyroiditis reflect their distinct and partially antagonistic roles in orchestrating the balance between degenerating and regenerating processes within a changing cytokine environment.

MHC class I target recognition, immunophenotypes and proteomic profiles of natural killer cells within the spleens of day-14 chick embryos

Chicken natural killer (NK) cells are not well defined, so little is known about the molecular interactions controlling their activity. At day 14 of embryonic development, chick spleens are a rich source of T-cell-free CD8αα(+), CD3(-) cells with natural killing activity. Cell-mediated cytotoxicity assays revealed complex NK cell discrimination of MHC class I, suggesting the presence of multiple NK cell receptors. Immunophenotyping of freshly isolated and recombinant chicken interleukin-2-stimulated d14E CD8αα(+) CD3(-) splenocytes provided further evidence for population heterogeneity. Complex patterns of expression were found for CD8α, chB6 (Bu-1), CD1-1, CD56 (NCAM), KUL01, CD5, and CD44. Mass spectrometry-based proteomics revealed an array of NK cell proteins, including the NKR2B4 receptor. DAVID and KEGG analyses and additional immunophenotyping revealed NK cell activation pathways and evidence for monocytes within the splenocyte cultures. This study provides an underpinning for further investigation into the specificity and function of NK cells in birds.

CD20+ tumor-infiltrating lymphocytes have an atypical CD27- memory phenotype and together with CD8+ T cells promote favorable prognosis in ovarian cancer

PURPOSE

Tumor-infiltrating lymphocytes (TIL), in particular CD8(+) T cells and CD20(+) B cells, are strongly associated with survival in ovarian cancer and other carcinomas. Although CD8(+) TIL can mediate direct cytolytic activity against tumors, the role of CD20(+) TIL is poorly understood. Here, we investigate the possible contributions of CD20(+) TIL to humoral and cellular tumor immunity.

EXPERIMENTAL DESIGN

Tumor and serum specimens were obtained from patients with high-grade serous ovarian cancer. CD8(+) and CD20(+) TIL were analyzed by immunohistochemistry and flow cytometry. Immunoglobulin molecules were evaluated by DNA sequencing. Serum autoantibody responses to the tumor antigens p53 and NY-ESO-1 were measured by ELISA.

RESULTS

The vast majority of CD20(+) TIL were antigen experienced, as evidenced by class-switching, somatic hypermutation, and oligoclonality, yet they failed to express the canonical memory marker CD27. CD20(+) TIL showed no correlation with serum autoantibodies to p53 or NY-ESO-1. Instead, they colocalized with activated CD8(+) TIL and expressed markers of antigen presentation, including MHC class I, MHC class II, CD40, CD80, and CD86. The presence of both CD20(+) and CD8(+) TIL correlated with increased patient survival compared with CD8(+) TIL alone.

CONCLUSIONS

In high-grade serous ovarian tumors, CD20(+) TIL have an antigen-experienced but atypical CD27(-) memory B-cell phenotype. They are uncoupled from serum autoantibodies, express markers of antigen-presenting cells, and colocalize with CD8(+) T cells. We propose that the association between CD20(+) TIL and patient survival may reflect a supportive role in cytolytic immune responses.

[Mycosis fungoides in children and adolescents: a report of six cases with predominantly hypopigmentation, along with a literature review]

Mycosis fungoides (MF), the most common form of cutaneous T cell lymphoma (CTCL), is mainly manifested in the elderly. However, it has been described in children and teenagers.

OBJECTIVES

To report six patients with mycosis fungoides diagnosed in patients under 20 years of age. Our focus is on epidemiologic data, clinical features, histopathological aspects, and immunophenotypical findings.

METHODS

The files of all patients diagnosed with CTCL at Hospital Universitário Antônio Pedro (HUAP) / Universidade Federal Fluminense (UFF), Niterói, Brazil, from 2007 to 2010 were searched to identify patients under 20 years of age. Slides were reviewed with routine methods (H&E) and immunohistochemical stains by two dermatopathologists and one surgical pathologist.

RESULTS

Among a total of 66 patients with MF, six were children and adolescents between five and nineteen years of age. Most of them had dark skin and presented with the hypopigmented variant of MF; some expressed the T cell CD8+ phenotype, although the prognosis remains the same as for classical CTCL. The main histopathological findings were basilar lymphocytes, Pautrier microabscesses, eccrine infiltration, and dermal fibrosis. One patient had shown pityriasis lichenoides chronica for 10 years before the diagnosis of MF.

CONCLUSIONS

The incidence of juvenile mycosis fungoides has increased, corresponding to 9.1 percent of patients diagnosed with MF in our institution in four years. In this sample, 83.3 percent of the patients had the hypopigmented variant and 50 percent of them showed the CD3+/CD8+ T cells phenotype. We emphasize the occurrence of pityriasis lichenoides chronica before the onset of MF in one of our cases. This association, although rare, must be considered in cases of atypical evolution of PLC. The diagnosis of hypopigmented MF should also be considered in patients when hypochromic patches are persistent. We would like to highlight the importance of Pautrier microabscesses, basilar distribution, and eccrine involvement by neoplastic lymphocytes as histopathological diagnostic criteria for this variant of MF.

Thymopoiesis and regulatory T cells in healthy children and adolescents

OBJECTIVES

The purpose of this study was to investigate the association between T cell receptor excision circle levels in peripheral blood mononuclear cells and regulatory T cells that co-express CD25 and Foxp3 in healthy children and adolescents of different ages.

MATERIALS AND METHODS

The quantification of signal-joint T-cell receptor excision circle levels in the genomic DNA of peripheral blood mononuclear cells was performed using real-time quantitative PCR. The analysis of CD4, CD8, CD25, and Foxp3 expression was performed using flow cytometry.

RESULTS

Ninety-five healthy controls (46 females and 49 males) ranging in age from 1 to 18 years were analyzed. The mean T-cell receptor excision circle count in all individuals was 89.095 ± 36.790 T-cell receptor excision circles per microgram of DNA. There was an inverse correlation between T-cell receptor excision circles counts and age (r = -0.846; p<0.001) as well as between the proportion of CD4(+)CD25(+)Foxp3(+) T cells and age (r = -0.467; p = 0.04). In addition, we observed a positive correlation between the amount of CD4(+)CD25(+)Foxp3(+) T cells and the amount of T-cell receptor excision circles per microgram of DNA in individuals of all ages (r = -0.529; p = 0.02).

CONCLUSIONS

In this study, we observed a decrease in the thymic function with age based on the fact that the level of T-cell receptor excision circles in the peripheral blood positively correlated with the proportion of regulatory T cells in healthy children and adolescents. These findings indicate that although T-cell receptor excision circles and regulatory T cells levels decrease with age, homeostasis of the immune system and relative regulatory T cells population levels are maintained in the peripheral blood.

High dose and low dose Lactobacillus acidophilus exerted differential immune modulating effects on T cell immune responses induced by an oral human rotavirus vaccine in gnotobiotic pigs

BACKGROUND

Strain-specific effects of probiotics in pro- or anti-inflammatory immune responses have been well recognized. Several proinflammatory Lactobacillus strains have been shown to act as adjuvants to enhance the immunogenicity of vaccines. However, dose effects of probiotics in modulating immune responses are not clearly understood. This study examined the dose effects of Lactobacillus acidophilus (LA) NCFM strain on T cell immune responses to rotavirus vaccination in a gnotobiotic (Gn) pig model.

METHODS

Frequencies of IFN-γ producing CD4+ and CD8+ T cell and IL-10 and TGF-β producing CD4+CD25+ and CD4+CD25- regulatory T (Treg) cell responses were determined in the intestinal and systemic lymphoid tissues of Gn pigs vaccinated with an oral human rotavirus vaccine in conjunction with low dose (5 feedings; up to 10(6) colony forming units [CFU]/dose) or high dose (14 feedings; up to 10(9)CFU/dose) or without LA feeding.

RESULTS

Low dose LA significantly promoted IFN-γ producing T cell responses and down-regulated Treg cell responses and their TGF-β and IL-10 productions in all the tissues compared to the high dose LA and control groups. To the contrary, high dose LA increased the frequencies of Treg cells in most of the tissues compared to the control groups. The dose effects of LA on IFN-γ producing T cell and CD4+CD25- Treg cell immune responses were similar in the intestinal and systemic lymphoid tissues and were independent from the vaccination.

CONCLUSION

Thus the same probiotic strain in different doses can either promote or suppress IFN-γ producing T cell or Treg cell immune responses. These findings have significant implications in the use of probiotic lactobacilli as immunostimulatory versus immunoregulatory agents. Probiotics can be ineffective or even detrimental if not used at the optimal dosage for the appropriate purposes.

Cellular immune responses in Echinostoma caproni experimentally infected mice

The Echinostoma caproni-mice system is extensively used as an experimental model for the study of the factors involved in the establishment of chronic intestinal helminth infections. Although several parameters of the immunobiology of the host-parasite system have been studied in detail, the current knowledge of the cellular responses in these infections is still scarce. In the present paper, we analyze the kinetics of the circulating CD3(+) and CD19(+) cell populations and the different T-cell phenotype profiles in mice experimentally infected with E. caproni. Whereas the CD3(+) populations remained stable during the complete experiment, a marked increase in CD19(+) cells was observed from 4 weeks post-infection and beyond. Similarly, a marked increase in CD8(+) cell populations was observed in the 2 week post-infection. Our results show that E. caproni infection in mice alters the peripheral lymphoid cell populations, which may be important to determine the course of the infection. In this sense, CD8(+) cells can be essential in relation to their role as a source of IFN-γ.

Chagasic thymic atrophy does not affect negative selection but results in the export of activated CD4+CD8+ T cells in severe forms of human disease

Extrathymic CD4⁺CD8⁺ double-positive (DP) T cells are increased in some pathophysiological conditions, including infectious diseases. In the murine model of Chagas disease, it has been shown that the protozoan parasite Trypanosoma cruzi is able to target the thymus and induce alterations of the thymic microenvironment and the lymphoid compartment. In the acute phase, this results in a severe atrophy of the organ and early release of DP cells into the periphery. To date, the effect of the changes promoted by the parasite infection on thymic central tolerance has remained elusive. Herein we show that the intrathymic key elements that are necessary to promote the negative selection of thymocytes undergoing maturation during the thymopoiesis remains functional during the acute chagasic thymic atrophy. Intrathymic expression of the autoimmune regulator factor (Aire) and tissue-restricted antigen (TRA) genes is normal. In addition, the expression of the proapoptotic Bim protein in thymocytes was not changed, revealing that the parasite infection-induced thymus atrophy has no effect on these marker genes necessary to promote clonal deletion of T cells. In a chicken egg ovalbumin (OVA)-specific T-cell receptor (TCR) transgenic system, the administration of OVA peptide into infected mice with thymic atrophy promoted OVA-specific thymocyte apoptosis, further indicating normal negative selection process during the infection. Yet, although the intrathymic checkpoints necessary for thymic negative selection are present in the acute phase of Chagas disease, we found that the DP cells released into the periphery acquire an activated phenotype similar to what is described for activated effector or memory single-positive T cells. Most interestingly, we also demonstrate that increased percentages of peripheral blood subset of DP cells exhibiting an activated HLA-DR⁺ phenotype are associated with severe cardiac forms of human chronic Chagas disease. These cells may contribute to the immunopathological events seen in the Chagas disease.

The thymus is a primary lymphoid organ that plays an important role on the development of the immune system and maturation of the T cell repertoire. During the normal life span, this organ undergoes involution during the aging and also in the presence of a wide variety of infectious diseases. It has been shown that the protozoan parasite Trypanosoma cruzi is able to target the thymus and induce alterations of the thymic microenvironment. In the acute phase, this results in a severe atrophy of the organ and early release of immature double-positive (DP) T cells into the periphery. The effect of the changes promoted by the parasite infection on thymic central tolerance has remained not clear. The present study shows that the intrathymic key elements that promote the negative selection of thymocytes during the thymopoiesis remains functional in the acute chagasic thymic atrophy. However, we found that the DP cells released into the periphery acquire an activated phenotype and its high frequency in the peripheral blood are associated with severe cardiac forms of human chronic Chagas disease.

Characterization of peripheral blood T lymphocyte subsets in Chinese rhesus macaques with repeated or long-term infection with Plasmodium cynomolgi

T lymphocytes play a vital role in antimalaria immunity, but there is little information about the role of T cells in malaria infection. In order to explore the profile of T cells in malaria immunity, we infected Chinese rhesus macaques with the malaria parasite (Plasmodium cynomolgi) and examined the dynamics of T cell subsets. Both repeated and long-term infections were involved. Our results showed that the monkeys in the repeated infection group acquired protective immunity through primary infection, which was evidenced by a much lower parasitemia, milder anemia, and milder fever during reinfection; the monkeys in the long-term infection group also developed protective immunity, but this was not sufficient to eliminate the parasite. The total counts of leukocytes, neutrophils, CD3+ T cells, CD4+ or CD8+ T cells, and naïve and memory CD4+ and CD8+ T cells declined during the acute phase of malaria but increased after the parasite was controlled. The total number of activated CD4+ T cells significantly increased during malaria in animals with a long-term infection, which remained at least 3 months after the termination of malaria. However, the activated CD4+ T cells decreased during the acute phase of infection in the repeated infection group and converted to preinfection levels after malaria was cured. Regulatory CD4+ T cells continued to increase during the malaria infections and quickly reverted to preinfection levels after the parasite was controlled. Our study provides a systematic analysis of the kinetic profiles of T lymphocyte subsets during malaria infections and provides some experimental insight into malaria immunology.

Simultaneous detection of T lymphocyte-related antigens (CD4/CD8, CD57, TCRβ) with nuclei by fluorescence-based immunohistochemistry in paraffin-embedded human lymph node, liver cancer and stomach cancer

OBJECTIVE

To develop a method for immunohistochemical staining of three different T lymphocyte antigens (CD4 or CD8, CD57 and TCRβ) on the same tissue section and to determine whether tissues have been infiltrated with T lymphocytes expressing these markers.

STUDY DESIGN

Commercially available antibodies were tested for immunohistochemical usefulness in a dye-based conventional single-immunostaining method after antigen retrieval on paraffin-embedded human lymph nodes. We searched for the combination of antibodies that could detect T lymphocyte antigens on the same section without any cross-reactivity and that have fluorescent signals robust enough to overcome paraffin autofluorescence.

RESULTS

Application of the antigen retrieval technique and the Sudan black B quenching technique enabled staining of paraffin-embedded tissue sections with fluorescent-labeled secondary antibodies. The combination of primary and secondary antibodies that could simultaneously detect the T lymphocyte antigens CD4 or CD8, CD57 and TCRβ in histochemical analysis of a paraffin-embedded human lymph node section was established, and was successfully applied to a human tissue section infiltrated with T lymphocytes that express these markers.

CONCLUSION

The antibodies listed here would be helpful for histopathologists who wish to investigate T lymphocytes in the paraffin-embedded sections that have accumulated in pathology labs throughout the world.

Early short-term antiretroviral therapy is associated with a reduced prevalence of CD8(+)FoxP3(+) T cells in simian immunodeficiency virus-infected controller rhesus macaques

Regulatory T cells contain a mix of CD4 and CD8 T cell subsets that can suppress immune activation and at the same time suppress immune responses, thereby contributing to disease progression. Recent studies have shown that an increased prevalence of CD8(+)FoxP3(+) T regulatory cells was associated with immune suppression and diminished viral control in simian immunodeficiency virus (SIV)-infected rhesus macaques. Preventing an increase in the prevalence of CD8 T regulatory subsets is likely to lead to a better long-term outcome. Here we show that short-term antiretroviral therapy initiated within 1 week after SIV infection was associated with lower viral set point and immune activation after withdrawal of therapy as compared to untreated animals. Early short-term treated controller animals were found to have better SIV-specific immune responses and a significantly lower prevalence of immunosuppressive CD8(+)FoxP3(+) T cells. Lower levels of CD8(+)FoxP3(+) T cells coincided with preservation of CD4(+)FoxP3(+) T cells at homeostatic levels, and significantly correlated with lower immune activation, suggesting a role for viral infection-driven immune activation in the expansion of CD8(+)FoxP3(+) T cells. Interestingly, initiation of continuous therapy later in infection did not reduce the increased prevalence of CD8(+)FoxP3(+) T cells to homeostatic levels. Taken together, our results suggest that early antiretroviral therapy preserves the integrity of the immune system leading to a lower viral set point in controller animals, and prevents alterations in the homeostatic balance between CD4(+) and CD8(+) T regulatory cells that could aid in better long-term outcome.

Trypanosoma cruzi in the chicken model: Chagas-like heart disease in the absence of parasitism

BACKGROUND

The administration of anti-trypanosome nitroderivatives curtails Trypanosoma cruzi infection in Chagas disease patients, but does not prevent destructive lesions in the heart. This observation suggests that an effective treatment for the disease requires understanding its pathogenesis.

METHODOLOGY/PRINCIPAL FINDINGS

To understand the origin of clinical manifestations of the heart disease we used a chicken model system in which infection can be initiated in the egg, but parasite persistence is precluded. T. cruzi inoculation into the air chamber of embryonated chicken eggs generated chicks that retained only the parasite mitochondrial kinetoplast DNA minicircle in their genome after eight days of gestation. Crossbreeding showed that minicircles were transferred vertically via the germ line to chicken progeny. Minicircle integration in coding regions was shown by targeted-primer thermal asymmetric interlaced PCR, and detected by direct genomic analysis. The kDNA-mutated chickens died with arrhythmias, shortness of breath, cyanosis and heart failure. These chickens with cardiomyopathy had rupture of the dystrophin and other genes that regulate cell growth and differentiation. Tissue pathology revealed inflammatory dilated cardiomegaly whereby immune system mononuclear cells lyse parasite-free target heart fibers. The heart cell destruction implicated a thymus-dependent, autoimmune; self-tissue rejection carried out by CD45(+), CD8γδ(+), and CD8α lymphocytes.

CONCLUSIONS/SIGNIFICANCE

These results suggest that genetic alterations resulting from kDNA integration in the host genome lead to autoimmune-mediated destruction of heart tissue in the absence of T. cruzi parasites.