Phase I/II study of adjuvant immunotherapy with sentinel lymph node T lymphocytes in patients with colorectal cancer

Although the development of multi-disciplinary management has improved the survival of colorectal cancer (CRC), the prognosis of metastatic CRC patients remains poor. Accumulating evidence has demonstrated that immunotherapy with cancer vaccines and adoptive T cell transfusions may improve outcomes as an adjuvant to current standard CRC treatment. In this phase I/II study, 71 CRC patients who underwent radical surgery (stage I-III, n = 46) or palliative surgery (stage IV with non-resectable synchronous metastases, n = 25) were included. In the first part of this study, sentinel lymph nodes (SLNs) were intraoperatively identified in 55 patients (46 with stage I-III CRC and 9 with stage IV CRC). SLN-T lymphocytes were expanded ex vivo for a median of 28.5 days (range 23-33 days). Thereafter, a median of 153 × 10(6) cells (range 20.7-639.0 × 10(6)) were transfused. No treatment-related toxicity was observed. In the second part of this study, the stage IV patients were routinely followed. The 24-month survival rate of the SLN-T lymphocyte group was significantly higher than that of the control group: 55.6 versus 17.5% (p = 0.02). The median overall survival of the SLN-T lymphocyte and control groups was 28 and 14 months, respectively. Our study showed that adjuvant SLN-T lymphocyte immunotherapy is feasible and safe for postoperative CRC patients. Additionally, this therapy may improve the long-term survival of metastatic CRC. Further investigation of the clinical efficacy and anti-tumor immunity is warranted.

Deprived TLR9 expression in apparently healthy nasal mucosa might trigger polyp-growth in chronic rhinosinusitis patients

Background

The origin of nasal polyps in chronic rhinosinusitis is unknown, but the role of viral infections in polyp growth is clinically well established. Toll-like receptors (TLRs) have recently emerged as key players in our local airway defense against microbes. Among these, TLR9 has gained special interest in viral diseases. Many studies on chronic rhinosinusitis with nasal polyps (CRSwNP) compare polyp tissue with nasal mucosa from polyp-free individuals. Knowledge about changes in the turbinate tissue bordering the polyp tissue is limited.

Objectives

To analyse the role of TLR9 mediated microbial defense in tissue bordering the polyp.

Methods

Nasal polyps and turbinate tissue from 11 patients with CRSwNP and turbinate tissue from 11 healthy controls in total were used. Five biopsies from either group were analysed immediately with flow cytometry regarding receptor expression and 6 biopsies were used for in vitro stimulation with a TLR9 agonist, CpG. Cytokine release was analysed using Luminex. Eight patients with CRSwNP in total were intranasally challenged with CpG/placebo 24 hours before surgery and the biopsies were collected and analysed as above.

Results

TLR9 expression was detected on turbinate epithelial cells from healthy controls and polyp epithelial cells from patients, whereas TLR9 was absent in turbinate epithelial cells from patients. CpG stimulation increased the percentage cells expressing TLR9 and decreased percentage cells expressing VEGFR2 in turbinate tissue from patients. After CpG stimulation the elevated levels of IL-6, G-CSF and MIP-1β in the turbinate tissue from patients were reduced towards the levels demonstrated in healthy controls.

Conclusion

Defects in the TLR9 mediated microbial defense in the mucosa adjacent to the anatomic origin of the polyp might explain virus induced polyp growth. CpG stimulation decreased VEGFR2, suggesting a role for CpG in polyp formation. The focus on turbinate tissue in patients with CRSwNP opens new perspectives in CRSwNP-research.

Evaluation of T and B lymphocyte function in clinical practice using a flow cytometry based proliferation assay

The golden standard for functional evaluation of immunodeficiencies is the incorporation of [(3)H]-thymidine in a proliferation assay stimulated with mitogens. Recently developed whole blood proliferation assays have the advantage of parallel lymphocyte lineage analysis and in addition provide a non-radioactive alternative. Here we evaluate the Flow-cytometric Assay for Specific Cell-mediated Immune-response in Activated whole blood (FASCIA) in a comparison with [(3)H]-thymidine incorporation in four patients with severe combined immunodeficiency. The threshold for the minimum number of lymphocytes required for reliable responses in FASCIA is determined together with reference values from 100 healthy donors when stimulated with mitogens as well as antigen specific stimuli. Finally, responses against PWM and SEA+SEB stimuli are conducted with clinically relevant immunomodulatory compounds. We conclude that FASCIA is a rapid, stable and sensitive functional whole blood assay that requires small amounts of whole blood that can be used for reliable assessment of lymphocyte reactivity in patients.

Activation of basophils is a new and sensitive marker of biocompatibility in hemodialysis

The hemodialysis procedure involves contact between peripheral blood and the surface of dialyzer membranes, which may lead to alterations in the pathways of innate and adaptive immunity. We aimed to study the effect of blood–membrane interaction on human peripheral basophils and neutrophils in hemodialysis with high- and low-permeability polysulfone dialyzers. The surface expression of CD203c (basophil selection marker) and CD63 (activation marker) after activation by the bacterial peptide formyl-methionyl-leucyl-phenylalanine (fMLP) or anti-Fcε receptor I (FcεRI) antibody and the absolute number of basophils was investigated before and after hemodialysis with each of the dialyzers. Moreover, the expression on neutrophils of CD11b, the CD11b active epitope, and CD88 was analyzed in the same groups of individuals. The expression of CD63 in basophils following activation by fMLP was significantly higher in the patient group compared with that in healthy controls, but no differences were observed after activation by anti-FcεRI. During the hemodialysis procedure, the low-flux membrane induced up-regulation of CD63 expression on basophils, while passage through the high-flux membrane did not significantly alter the responsiveness. In addition, the absolute number of basophils was unchanged after hemodialysis with either of the dialyzers and compared with healthy controls. We found no significant differences in the expression of the neutrophil activation markers (CD11b, the active epitope of CD11b, and CD88) comparing the two different dialyzers before and after dialysis and healthy controls. Together, these findings suggest that alterations in basophil activity may be a useful marker of membrane bioincompatibility in hemodialysis.

Peripheral and site-specific CD4(+) CD28(null) T cells from rheumatoid arthritis patients show distinct characteristics

Proinflammatory CD4(+) CD28(null) T cells are frequently found in the circulation of patients with rheumatoid arthritis (RA), but are less common in the rheumatic joint. In the present study, we sought to identify functional differences between CD4(+) CD28(null) T cells from blood and synovial fluid in comparison with conventional CD28-expressing CD4(+) T cells. Forty-four patients with RA, displaying a distinct CD4(+) CD28(null) T cell population in blood, were recruited for this study; the methylation status of the IFNG locus was examined in isolated T cell subsets, and intracellular cytokine production (IFN-γ, TNF, IL-17) and chemokine receptor expression (CXCR3, CCR6 and CCR7) were assessed by flow cytometry on T cells from the two compartments. Circulating CD4(+) CD28(null) T cells were significantly more hypomethylated in the CNS-1 region of the IFNG locus than conventional CD4(+) CD28(+) T cells and produced higher levels of both IFN-γ and TNF after TCR cross-linking. CD4(+) CD28(null) T cells from the site of inflammation expressed significantly more CXCR3 and CCR6 compared to their counterparts in blood. While IL-17A production could hardly be detected in CD4(+) CD28(null) cells from the blood, a significant production was observed in CD4(+) CD28(null) T cells from synovial fluid. CD4(+) CD28(null) T cells were not only found to differ from conventional CD4(+) CD28(+) T cells in the circulation, but we could also demonstrate that synovial CD4(+) CD28(null) T cells showed additional effector functions (IL-17 coproduction) as compared to the same subset in peripheral blood, suggesting an active role for these cells in the perpetuation of inflammation in the subset of patients having a CD28(null) population.

Naïve T cells correlate with mucosal healing in patients with inflammatory bowel disease

BACKGROUND

In previous studies, adaptive immune responses involving T-helper cells have been shown to play an important role in inflammatory bowel diseases (IBDs).

METHODS

The aim of this study was to investigate any correlation between the degree of mucosal inflammation and the phenotype of gut-infiltrating T-helper cells. Biopsies from intestinal mucosa were obtained and intestinal T cells were analyzed with regard to activity and maturation markers. Patients with active colitis (39 with Crohn's disease and 47 with ulcerative colitis) were included and treated with corticosteroids, biologicals or leukocytapheresis. Flow cytometry was used to analyze activation marker expression on gut-infiltrating T-helper cells.

RESULTS

Mucosal healing was reflected by almost 100% increase of CD62L expression in mucosal T cells in patients in remission compared to those with active inflammation (p < 0.01). The frequency of mucosal-naïve CD4(+)CD45RA(+) T cells was reduced by 50% in mucosa displaying remission (5.3% compared to 12% of the total amount and CD4(+) T cells, p < 0.001). Surprisingly, the proportion of early activated T-helper cells (CD4(+)CD69(+)) did not differ between mucosa in remission and non-remission (43% and 42%, respectively). Moreover, no change in memory T-helper cells (CD4(+)CD45RO(+)) was observed (64% compared to 66%). The findings were independent of diagnosis (Crohn's disease or ulcerative colitis) or mode of treatment.

CONCLUSION

This study suggests that a reduced recruitment of naïve T-helper cells and increased frequency of T-helper cells with lymph node homing marker expression reflect mucosal healing in IBD. Surprisingly, the degree of activation of mucosal T-helper cells did not correlate with disease remission.

Dynamic Toll-like receptor expression predicts outcome of sclerotherapy for lymphatic malformations with OK-432 in children

BACKGROUND

Sclerotherapy with OK-432 is recommended as a first-line treatment for lymphatic malformations. However, 40% of patients show poor response, defined by involution to <50% of the original size. It has been suggested that the OK-432 effect is highly dependent on the Toll-like receptor (TLR) 4-dependent expression of TLR7 in antigen-presenting cells. We hypothesized that the ability for TLR expression in monocytes after treatment with the TLR4-ligand lipopolysaccharide (LPS) can be used to predict successful OK-432 treatment.

METHODS

Blood was taken from children with low responder (LR, n = 6) and high responder (HR, n = 5) of previous OK-432 treatment. Monocytes were stimulated with LPS for 20 h. TLR expression was analyzed with fluorescence-activated cell sorting (mean fluorescence intensity). The level of significance was P ≤ 0.05.

RESULTS

The mean age of patients in the HR group was 1.4 ± 0.9 y and in the LR group 2.8 ± 2.9 y (P = 0.31). The mean TLR4 upregulation after LPS stimulation in the HR group was significantly higher than in the LR group (factor 3.6 versus factor 1 compared with nonstimulated controls; P = 0.037). The mean TLR7 expression did not show significant differences between the groups.

CONCLUSIONS

Dynamic TLR4 expression represents most probably a predictive parameter for the treatment of lymphatic malformations with OK-432 and should be further investigated.

The effects of chemotherapeutic drugs on human monocyte-derived dendritic cell differentiation and antigen presentation

Recent studies indicate that chemotherapeutic agents may increase the anti-tumoral immune response. Based on the pivotal role of dendritic cells (DCs) in host tumour-specific immune responses, we investigated the effect of commonly used chemotherapeutic drugs dexamethasone, doxorubicin, cisplatin and irinotecan and glucocorticoids on monocyte-derived DCs (moDCs). Dexamethasone displayed the strongest inhibitory effect on DC differentiation. The effect of cisplatin and irinotecan was moderate, while only weak effects were noticed for doxorubicin. Surprisingly, when the functional consequence of chemotherapy-treated CD14(+) monocytes and their capacity to activate CD4(+) T responders cells were investigated, cisplatin-treated monocytes gave rise to increased T cell proliferation. However, dexamethasone, doxorubicin and irinotecan-pretreated monocytes did not stimulate any increased T cell proliferation. Further investigation of this observation revealed that cisplatin treatment during DC differentiation up-regulated significantly the interferon (IFN)-β transcript. By contrast, no effect was evident on the expression of interleukin (IL)-1β, tumour necrosis factor (TNF)-α, IL-6 or IFN-α transcripts. Blocking IFN-β attenuated the cisplatin-enhanced T cell proliferation significantly. In conclusion, cisplatin treatment enhanced the immune stimulatory ability of human monocytes, a mechanism mediated mainly by the increased production of IFN-β.

Treatment of inflammatory bowel disease by chemokine receptor-targeted leukapheresis

Leukapheresis removes circulating leukocytes en route to the target organ. Hitherto unspecific matrixes have been used to remove leukocytes in inflammatory bowel disease (IBD). This report describes a novel selective leukapheresis column based on chemokine-chemokine receptor interaction. We found an increased expression of the gut homing chemokine receptor CCR9 on CD14(+) monocytes and on CD3(+) T lymphocytes from IBD patients. Biologically active CCL25 was coupled to a Sepharose matrix and demonstrated to selectively remove CCR9-expressing cells leaving other cell populations largely unaffected. A patient with active ulcerative colitis, was subjected to CCL25-column leukapheresis. Four days after treatment, he experienced clinical improvement and stable disease improvement ensued. The study illustrates that specific cells can be targeted using high affinity interactions, i.e., CCL25-CCR9 interactions to remove pathogenic gut-homing cells. Leukapheresis using the bCCL25 column should be investigated in a clinical phase I trial of patients with inflammatory bowel disease.

The many flavors of tumor-associated B cells

Little is known on the role of distinct B-cell subtypes in human malignancies. We have recently performed a multiplex characterization of B cells in patient-derived tumor-associated tissues, documenting the activation and antigen-driven differentiation of B cells in metastatic lymph nodes and neoplastic lesions. Here we discuss the role of B lymphocytes as antigen-presenting cells and catalysts of T cell-based immunotherapies in view of these findings.

AIRE expressing marginal zone dendritic cells balances adaptive immunity and T-follicular helper cell recruitment

Autoimmune polyendocrine syndrome Type I (APS I) results in multiple endocrine organ destruction and is caused by mutations in the Autoimmune regulator gene (AIRE). In the thymic stroma, cells expressing the AIRE gene dictate T cell education and central tolerance. Although this function is the most studied, AIRE is also expressed in the periphery in DCs and stromal cells. Still, how AIRE regulated transcription modifies cell behaviour in the periphery is largely unknown. Here we show that AIRE is specifically expressed by 33D1(+) DCs and dictates the fate of antibody secreting cell movement within the spleen. We also found that AIRE expressing 33D1(+) DCs expresses self-antigens as exemplified by the hallmark gene insulin. Also, as evidence for a regulatory function, absence of Aire in 33D1(+) DCs led to reduced levels of the chemokine CXCL12 and increased co-stimulatory properties. This resulted in altered activation and recruitment of T-follicular helper cells and germinal centre B cells. The altered balance leads to a change of the early response to a T cell-dependent antigen in Aire(-/-) mice. These findings add to the understanding of how specific DC subtypes regulate the early responses during T cell-dependent antibody responses within the spleen and further define the role of AIRE in the periphery as regulator of self-antigen expression and lymphocyte migration.

Multiplex B cell characterization in blood, lymph nodes, and tumors from patients with malignancies

B lymphocytes contribute to immune surveillance, by tumor-specific Abs and Ag presentation to T lymphocytes, but are insufficiently studied in humans. In this article, we report a flow cytometric investigation of B lymphocyte subpopulations in blood, lymph nodes (LNs), and malignant tissues from 20 patients operated on because of advanced solid tumors. The CD19(+) compartment in peripheral blood was essentially unaltered in patients, as compared with healthy control subjects. In metastatic LNs, signs of B lymphocyte activation were observed, as evidenced by increased proportions of plasmablasts and CD86-expressing cells. In tumor-infiltrating B lymphocytes (TIL-B), both switched memory cells and plasmablasts were expanded, as compared with nonmalignant epithelium. Moreover, pronounced skewing of Igλ/Igκ ratio was evident among TIL-Bs. By spectratype analysis on IgH, we confirmed a monoclonal expansion of the Vh7 family in TIL-B, also present in a tumor-associated LN. Sequencing the clonally expanded Vh7 revealed signs of somatic hypermutation. In conclusion, B lymphocytes in cancer patients exhibit signs of activation in tumor-associated tissues, likely induced by recognition of tumor Ags. Increased numbers of switched memory cells and plasmablasts in combination with clonal expansion and signs of somatic hypermutation suggest a CD4(+) T lymphocyte-dependent antitumoral response, which may be exploited for immunotherapy.

Activated monocytes augment TRAIL-mediated cytotoxicity by human NK cells through release of IFN-γ

Natural killer (NK) cells are innate lymphocytes that are able to directly kill tumor cells through different mechanisms including ligation of TNF-related apoptosis-inducing ligand (TRAIL) receptors. Zoledronic acid (ZA) is a bisphosphonate known to upregulate the expression of TRAIL on human γδ T cells. Here, we investigated whether exposure to ZA would upregulate TRAIL expression on human NK cells and augment their cytotoxicity against tumor cells. When cocultured with monocytes, treatment with ZA and IL-2 resulted in a significant upregulation of TRAIL expression on human NK cells (p = 0.002). Consequently, ZA-primed NK cells were significantly more cytotoxic against TRAIL sensitive tumor cells (p < 0.0001). In the presence of ZA and IL-2, monocytes produced high levels of IFN-γ; when cultured in the presence of neutralizing antibodies to IFN-γ, TRAIL expression and TRAIL-mediated cytotoxicity of NK cells were significantly reduced. Furthermore, in tumor-bearing SCID/Beige mice, a significant delayed tumor progression and prolonged survival was observed after infusion of ZA-primed NK cells compared with that observed in mice infused with unprimed NK cells. These findings represent a novel approach to potentiate TRAIL-mediated apoptosis by adoptively infused NK cells that could improve the outcome in patients with cancer.

LPS regulates SOCS2 transcription in a type I interferon dependent autocrine-paracrine loop

Recent studies suggest that SOCS2 is involved in the regulation of TLR signaling. In this study, we found that the expression of SOCS2 is regulated in human monocyte-derived DC by ligands stimulating TLR2, 3, 4, 5, 8 and 9 signaling. SOCS2 induction by LPS was dependent on the type I IFN regulated transcription factors IRF1 and IRF3 as shown by using silencing RNAs for IRFs. Blocking endogenous type I IFN signaling, by neutralizing antibodies to the receptor IFNAR2, abolished SOCS2 mRNA expression after TLR4 stimulation. Transcription factors STAT3, 5 and 6 displayed putative binding sites in the promoter regions of the human SOCS2 gene. Subsequent silencing experiments further supported that STAT3 and STAT5 are involved in LPS induced SOCS2 regulation. In mice we show that SOCS2 mRNA induction is 45% lower in bone marrow derived macrophages derived from MyD88^−/− mice, and do not increase in BMMs from IRF3^−/− mice after BCG infection. In conclusion, our results suggest that TLR4 signaling indirectly increases SOCS2 in late phase mainly via the production of endogenous type I IFN, and that subsequent IFN receptor signaling activates SOCS2 via STAT3 and STAT5.