Immune Effector Cell Populations Research Articles

Myeloid Derived Suppressor Cells and Their Potential Impact on Minimal Residual Disease Status and Disease Response in a Cohort of Patients with Plasma Cell Dyscrasias

Myeloid Derived Suppressor Cells (MDSCs) are known to promote immune-suppressive and tumorigenic effects in plasma cell dyscrasias (PCDs), including multiple myeloma, and may play a role in treatment response and minimal residual disease MRD status in patients undergoing cancer-directed therapies. MDSCs are classified by their granulocyte-like effects (g-MDSCs) or monocyte-like effects (m-MDSCs). To our knowledge, there are no published studies that correlate minimal residual disease (MRD) with the presence of MDSCs and immune effector-cell populations in the blood and bone marrow of patients with PCDs. In 14 patients with PCDs, we defined immune-cell populations in the blood and marrow and correlated them with MRD status, treatment regimens, disease status (stable vs. progressive) and autologous stem cell transplantation status. In the entire cohort, there were a higher proportion of m-MDSCs in blood (blood 5.56%, aspirate 2.47%). There were a higher proportion of g-MDSCs in aspirate (blood 0.04%, aspirate 0.16%). Interestingly, in patients who remained MRD positive (3/13), the proportions were reversed, and we identified more m-MDSC in aspirate than blood, as well as a low proportion of g-MDSCs in both the aspirate and bone marrow. In patients achieving undetectable MRD (10/13) there were higher proportions of CD8 and CD4 T-cells, with no differences in MDSC populations. Not surprisingly, in patients treated with the anti-CD38 antibody daratumumab (5/14), fewer m-MDSCs were isolated in the blood and aspirate, relative to daratumumab-untreated patients (9/14).Daratumumab treatment decreased activated CD4 and CD8 T cells (HLA-DR+/CD38-, HLA-DR-/CD38+ or HLA-DR+/CD38+ CD4 and CD8 T cells) and increased the proportion of inactive HLA-DR-/CD38- CD4 and CD8 T-cells. In patients with progressive disease (3/14), there was a paucity of all immune effector-cells, including MDSCs, T-cells and monocytes with the exception of neutrophils. MDSC populations were no different in pre-transplant patients (3/14) compared to post-transplant (11/14). In this preliminary study, we have enumerated the presence of MDSCs and their potential impact in patients with PCDs undergoing cancer-directed therapy.

Early dose escalation of LAVA-1207, a novel bispecific gamma-delta T-cell engager (Gammabody), in patients with metastatic castration-resistant prostate cancer (mCRPC).

153 Background: LAVA-1207 is a humanized bispecific antibody of 78 kDa comprised of two single domain antibody (VHH) fragments linked to a silenced fragment crystallizable immunoglobulin region. As shown pre-clinically, LAVA-1207 binds with high affinity to the Vδ2 chain of Vγ9Vδ2-T cells, a potent immune effector cell population, and to prostate specific membrane antigen (PSMA) expressed by prostate cancer cells to trigger robust (pM range EC50) Vγ9Vδ2-T cell mediated lysis of prostate cancer cells, whereas normal cells are relatively spared. Based on earlier clinical experience with systemic activation of Vγ9Vδ2-T cells through aminobisphosphonates and in vivo studies in non-human primates with cross-reactive surrogate bispecific γδ-T cell engagers, a low risk for cytokine release syndrome (CRS) is expected in the clinic. Methods: This is an open label, 3+3 design, phase 1/2a study in patients with therapy refractory metastatic castration resistant prostate cancer (NCT05369000; EudraCT Number: 2021-001789-39) to determine the safety of LAVA-1207 and its recommended Phase 2a dose (RP2D) and schedule. Secondary objectives include evaluation of PK, PD, immunogenicity, and preliminary antitumor activity. LAVA-1207 is administered IV every two weeks with an infusion duration of 2 hours for the first dose, 1 hour for the second dose, and 30 minutes for all subsequent doses. Results: As of September 23, 2022, a dose level of 40 µg (starting dose was 1.5 µg based on MABEL approach) has been reached without dose limiting toxicities (DLTs). A total of 16 patients have been treated with LAVA-1207 with treatment duration ranging from 1 to 25+ weeks. Treatment emergent AEs (TEAEs) that were suspected to be related were all grade 1-2, and included nausea (n=3), AST increase (n=2), fatigue (n=2), and infusion related reaction (n=2). Severity of TEAEs did not increase with escalating doses and no patient discontinued treatment due to an AE. PK data indicate increasing drug exposure in correlation with increasing doses of LAVA-1207. PD data show a consistent early reduction in Vγ9Vδ2-T cell frequencies at 2hrs after the first dose, which could be indicative of Vγ9Vδ2-T cell redistribution after treatment, often accompanied by an increase in Vγ9Vδ2-T cell activation markers. Vγ9Vδ2-T cell numbers are restored in the subsequent 3 to 5 days to at least pre-dose levels. Additionally, receptor occupancy of Vγ9Vδ2-T cells was detectable up to 5 days after first dosing. To date, stable disease at 8 weeks has been observed in 3 out of 8 evaluable patients. Conclusions: LAVA-1207 has been well tolerated early in dose escalation; further clinical activity including PSA results, response assessment, and pharmacodynamic data will clarify determination of an optimal biological active dose. Clinical trial information: NCT05369000 .

Bispecific antibody-derived molecules to target persistent HIV infection

HIV infection persists despite durable and potent antiviral therapy. To target persistent HIV infection, one major strategy aims to induce HIV provirus expression using latency reversing agents and then eliminate these reservoir cells via immune responses enhanced by treatment with antibody-derived bispecific molecules. The specificities of anti-HIV-1 envelope monoclonal antibodies have been incorporated into bispecific molecules that can recognize infected cells and recruit cytotoxic immune cells to eliminate them. This concept seeks to engineer a unique and potent effector response based on the opportunity to target conserved viral epitopes on infected cells, and recruit broad populations of immune effector cells that are not limited by major histocompatibility complex restrictions or other programmed specificity constraints. This article provides a review of bispecific DART® molecules and other dual-specificity antibody-based molecules that function by co-engaging CD3-expressing T cells or CD16A-expressing NK cells with HIV-1-infected cells.

Synergistic Benefit of Adoptive T Cells in Combination With Chemoradiotherapy Against Metastatic Prostate Cancer Cells.

Prostate cancer (PC) is one of the major diseases that affects male health and ranks as the second most frequent cancer in men worldwide. Although most newly-diagnosed PCs are well-differentiated tumors with a high cure probability, there are some patients with aggressive malignancies that show potential for recurrence and metastasis. Cytotoxic T lymphocytes are a specific immune effector cell population that mediates immune responses against cancer. In the present study, the cytotoxicity of peripheral blood mononuclear cells (PBMCs)-derived γδ T cells and cytokine-induced killer (CIK) cells in combination with chemoradiotherapy against PC cells was evaluated using Alamar blue cell viability and cell membrane permeability assays. Advanced PC-3 cells, which were more resistant to docetaxel (Doc), also showed higher viability following pretreatment with radiation. The cell proliferation inhibition was significantly increased upon additional γδ T or CIK treatment. Furthermore, the proportion of apoptotic cells was significantly (p<0.05) increased in the Doc-γδ T cell co-treatment group as compared with the Doc or γδ T cell treated alone group. γδ T cell therapy may provide additional benefit compared to traditional chemoradiotherapy for PC treatment.

Next Generation Natural Killer Cells for Cancer Immunotherapy

In recent years, immunotherapy for cancer has become mainstream with several products now authorized for therapeutic use in the clinic and are becoming the standard of care for some malignancies. Chimeric antigen receptor (CAR)-T cell therapies have demonstrated substantial efficacy for the treatment of hematological malignancies; however, they are complex and currently expensive to manufacture, and they can generate life-threatening adverse events such as cytokine release syndrome (CRS). The limitations of current CAR-T cells therapies have spurred an interest in alternative immunotherapy approaches with safer risk profiles and with less restrictive manufacturing constraints. Natural killer (NK) cells are a population of immune effector cells with potent anti-viral and anti-tumor activity; they have the capacity to swiftly recognize and kill cancer cells without the need of prior stimulation. Although NK cells are naturally equipped with cytotoxic potential, a growing body of evidence shows the added benefit of engineering them to better target tumor cells, persist longer in the host, and be fitter to resist the hostile tumor microenvironment (TME). NK-cell-based immunotherapies allow for the development of allogeneic off-the-shelf products, which have the potential to be less expensive and readily available for patients in need. In this review, we will focus on the advances in the development of engineering of NK cells for cancer immunotherapy. We will discuss the sourcing of NK cells, the technologies available to engineer NK cells, current clinical trials utilizing engineered NK cells, advances on the engineering of receptors adapted for NK cells, and stealth approaches to avoid recipient immune responses. We will conclude with comments regarding the next generation of NK cell products, i.e., armored NK cells with enhanced functionality, fitness, tumor-infiltration potential, and with the ability to overcome tumor heterogeneity and immune evasion.

Modulating tumor immunity by metronomic dosing of oxaliplatin incorporated in multiple oral nanoemulsion

In this study, a system for oral delivery of oxaliplatin (OXA) was prepared for metronomic chemotherapy to enhance antitumor efficacy and modulate tumor immunity. OXA was complexed with Nα-deoxycholyl-l-lysyl-methylester (DCK) (OXA/DCK) and formulated as a nanoemulsion (OXA/DCK-NE). OXA/DCK-NE showed 3.35-fold increased permeability across a Caco-2 cell monolayer, resulting in 1.73-fold higher oral bioavailability than free OXA. In addition, treatment of the B16F10.OVA cell line with OXA/DCK-NE resulted in successful upregulation of immunogenic cell death (ICD) markers both in vitro and in vivo. In a B16F10.OVA tumor-bearing mouse model, treatment with OXA/DCK-NE substantially impeded tumor growth by 63.9 ± 13.3% compared to the control group, which was also greater than the intravenous (IV) OXA group. Moreover, treatment with a combination of oral OXA/DCK-NE and anti-programmed cell death protein-1 (αPD-1) antibody resulted in 78.3 ± 9.67% greater inhibition compared to controls. More important, OXA/DCK-NE alone had immunomodulatory effects, such as enhancement of tumor antigen uptake, activation of dendritic cells in tumor-draining lymph nodes, and augmentation of both the population and function of immune effector cells in tumor tissue as well as in the spleen; no such effects were seen in the OXA IV group. These observations provide a rationale for combining oral metronomic OXA with immunotherapy to elicit synergistic antitumor effects.

Blood-brain barrier opening with low intensity pulsed ultrasound for immune modulation and immune therapeutic delivery to CNS tumors.

Opening of the blood-brain barrier (BBB) by pulsed low intensity ultrasound has been developed during the last decade and is now recognized as a safe technique to transiently and repeatedly open the BBB. This non- or minimally invasive technique allows for a targeted and uniform dispersal of a wide range of therapeutic substances throughout the brain, including immune cells and antibodies. In this review article, we summarize pre-clinical studies that have used BBB-opening by pulsed low intensity ultrasound to enhance the delivery of immune therapeutics and effector cell populations, as well as several recent clinical studies that have been initiated. Based on this analysis, we propose immune therapeutic strategies that are most likely to benefit from this strategy. The literature review and trial data research were performed using Medline/Pubmed databases and clinical trial registry www.clinicaltrials.gov . The reference lists of all included articles were searched for additional studies. A wide range of immune therapeutic agents, including small molecular weight drugs, antibodies or NK cells, have been safely and efficiently delivered to the brain with pulsed low intensity ultrasound in preclinical models, and both tumor control and increased survival have been demonstrated in different types of brain tumor models in rodents. Ultrasound-induced BBB disruption may also stimulate innate and cellular immune responses. Ultrasound BBB opening has just recently entered clinical trials with encouraging results, and the association of this strategy with immune therapeutics creates a new field of brain tumor treatment.

Multiple antibodies targeting tumor-specific mutations redirect immune cells to inhibit tumor growth and increase survival in experimental animal models.

T cell therapy for cancer involves genetic introduction of a target-binding feature into autologous T cells, ex vivo expansion and single large bolus administration back to the patient. These reprogrammed T cells can be highly effective in killing cells, but tumor heterogeneity results in regrowth of cells that do not sufficiently express the single antigen being targeted. We describe a cell-based therapy that simultaneously targets multiple tumor-specific antigens. High-affinity polyclonal rabbit antibodies were generated against nine different surface-related tumor-specific mutations on B16F10 cells. Unsorted splenic effector cells from syngeneic mice were incubated with a cocktail of the nine anti-B16F10 antibodies. These 'armed' effector cells were used to treat mice previously inoculated with B16F10 melanoma cells. The cocktail of nine antibodies resulted in dense homogeneous binding to histological sections of B16F10 cells. Five treatments with the armed effector cells and PD1 inhibition inhibited tumor growth and improved survival. Shortening the interval of the five treatments from every three days to every day increased survival. Arming effector cells with the four antibodies showing best binding to B16F10 cells even further increased survival. This study demonstrates that ex vivo arming a mixed population of immune effector cells with antibodies targeting multiple tumor-specific mutated proteins in conjunction with PD1 inhibition delayed tumor growth and prolonged survival in mice inoculated with an aggressive melanoma. A remarkably low total antibody dose of less than 5µg was sufficient to accomplish tumor inhibition. Scaling up to clinical level may be feasible.

Ectonucleotidase Expression on Human Amnion Epithelial Cells: Adenosinergic Pathways and Dichotomic Effects on Immune Effector Cell Populations.

This study investigates the mechanism(s) underlying the immunoregulatory activities of placenta-derived human amnion epithelial cells (hAEC). The working hypothesis is that NAD+ and ATP, along with ectoenzymes involved in their metabolism, play a significant role in hAEC-mediated immune regulation. Proof of principle of the hypothesis was obtained by analyzing the interactions between hAEC and the main human leukocyte populations. The results obtained indicate that hAEC constitutively express a unique combination of functional ectoenzymes, driving the production of adenosine (ADO) via canonical (CD39, CD73) and alternative (CD38, CD203a/PC-1, CD73) pathways. Further, the picture is completed by the observation that hAEC express A1, A2a, and A2b ADO receptors as well as ADO deaminase, the enzyme involved in ADO catabolism. The contribution of the purinergic mediator to immunomodulation was confirmed by exposing in vitro different immune effector cells to the action of primary hAECs. B cells showed an enhanced proliferation and diminished spontaneous apoptosis when in contact with hAEC. T cell proliferation was partially inhibited by hAEC through ADO production, as confirmed by using specific ectoenzyme inhibitors. Further, hAEC induced an expansion of both T and B regulatory cells. Last, hAEC inhibited NK cell proliferation. However, the involvement of ADO-producing ectoenzymes is less apparent in this context. In conclusion, hAEC exert different in vitro immunoregulatory effects, per se, as a result of interactions with different populations of immune effector cells. These results support the view that hAEC are instrumental for regenerative medicine as well as in therapeutic applications for immune-related diseases.

Update on PD-1/PD-L1 Inhibitors in Multiple Myeloma.

The treatment of cancer, especially of various types of solid tumors, has been revolutionized by the blockade of the PD-1/PD-L1 pathway by immune checkpoint inhibitors. Their success amongst hematologic malignancies, however, has been limited so far to the treatment of classic Hodgkin's lymphoma, which portrays a typical overexpression of PD-1 ligands (PD-L1, PD-L2) as a consequence of changes in chromosome 9p24.1. Their current application in multiple myeloma (MM) is rather uncertain, as discordant results have been reported by distinct research groups concerning especially the expression of PD-1/PD-L1 molecules on malignant plasma cells or on the responsible immune effector cell populations, respectively. In MM it seems that an approach based on combination treatment might be appropriate as unsatisfactory results have been yielded by monotherapy with PD-1/PD-L1 inhibitors. Immunomodulatory drugs, which are the current cornerstone of MM treatment, are the most logical partners as they possess many possibly synergistic effects. Nevertheless, the initially optimistic results have become disappointing due to the excessive and unpredictable toxicity of the combination of pembrolizumab with lenalidomide or pomalidomide. The FDA has suspended or put on hold several phase 3 trials in relapsed as well as in newly diagnosed myeloma patients. There are also other potentially synergistic and promising combinations, such as the anti-CD38 monoclonal antibody daratumumab, irradiation, etc. Not only the effective partner but also the correct timing of the initiation of the PD-1/PD-L1 inhibitors treatment seems to be of utmost importance. These strategies are currently being examined in various stages of myeloma such as during consolidation post autologous stem cell transplantation, targeting minimal residual disease or even in high risk smoldering myeloma.

RIVA \u2013 a phase IIa study of rituximab and varlilumab in relapsed or refractory B-cell malignancies: study protocol for a randomized controlled trial

BackgroundOver 12,000 new cases of B-cell malignancies are diagnosed in the UK each year, with diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) being the most common subtypes. Standard frontline therapy consists of immunochemotherapy with a CD20 monoclonal antibody (mAb), such as rituximab, delivered in combination with multi-agent chemotherapy. Despite being considered a treatable and potentially curable cancer, approximately 30% of DLBCL cases will relapse after frontline therapy. Advanced stage FL is incurable and typically has a relapsing and remitting course with a frequent need for re-treatment. Based on supportive preclinical data, we hypothesised that the addition of varlilumab (an anti-CD27 mAb) to rituximab (an anti-CD20 mAb) can improve the rate, depth and duration of the response of rituximab monotherapy in patients with relapsed or refractory B-cell malignancies.Methods/designCombination treatment of varlilumab plus rituximab, in two different dosing regimens, is being tested in the RIVA trial. RIVA is a two-stage open-label randomised phase IIa design in up to 40 patients with low- or high-grade relapsed or refractory CD20+ B-cell lymphoma. The study is open to recruitment in the UK. Enrolled patients are randomised 1:1 to two different experimental varlilumab to rituximab combinations.The primary objective is to determine the safety and tolerability of the combination and the anti-tumour activity (response) in relapsed or refractory B-cell malignancies. Secondary objectives will include an evaluation of the duration of the response and overall survival. Tertiary translational objectives include assessment of B-cell depletion, changes in immune effector cell populations, expression of CD27 as a biomarker of response and pharmacokinetic properties. Analyses will not be powered for formal statistical comparisons between treatment arms.DiscussionRIVA will determine whether the combination of rituximab and varlilumab in relapsed or refractory B-cell malignancies is active and safe prior to future phase II/III trials.Trial registrationEudraCT, 2017–000302-37. Registered on 16 January 2017. ISRCTN, ISRCTN15025004. Registered on 16 August 2017.

Chemoradiation Combined with Phosphatidylserine-Targeting Antibody Enhances Systemic Anti-tumor Immune Responses

Recent advances in cancer immunotherapy have sparked significant interest in harnessing the body’s immune system to fight cancer. However, the response rates of cancer immunotherapies, including immune checkpoint blockade, remain low. Strategies to enhance anti-tumor immune responses by targeting different steps along the immune activation cascade that can complement T cell-based immunotherapies are clearly needed. Here, we examine whether the addition of an antibody that targets extracellular phosphatidylserine (PS), a molecule that is recognized by myeloid derived cells, can enhance anti-tumor immune responses of chemoradiation for non-small cell lung cancer (NSCLC). Chemoradiation (CRT) was combined with a murine monoclonal antibody (mch1N11). PS is highly expressed in both orthotopically and ectopically implanted 393P murine NSCLC models. Radiation dose was 2 Gy/day, given for 5 days. Chemotherapy consists of carboplatin and paclitaxel at a dose of 30 mg/kg and 10 mg/kg, respectively. PS-targeting antibody (mch1N11) was given at 3mg/kg for 2 weekly doses. For ectopic tumor models, bilateral tumors were established in the legs. Radiation was directed to the R leg and tumor on the L side was shielded. Tumor growth was measured either with CT imaging or digital caliper. Tumor infiltrating immune cell profiles were analyzed using immunohistochemistry. Survival analyses were performed using Kaplan-Meier method and compared using Log-rank test. CRT + mch1N11 treatment significantly inhibited growth and improved survival in mice implanted with orthotopic 393P tumors as compared to CRT alone (median: 21 vs. 15 days, HR: 2.77, P = 0.006). Tissue analyses showed that CRT significantly increased the expression of PD-L1 within the tumor and drastically reduced the number of tumor infiltrating CD8 T cells. For the CRT + mch1N11 group, a similar up-regulation of PD-L1 expression was noted. However, the addition of mch1N11 re-populated the infiltrating CD8 T cells within the tumor. In the bilateral tumor model, the addition of mch1N11 antibody to CRT resulted in tumor regression in ∼40% of the non-irradiated tumors in the contralateral side as compared to 0% in the CRT alone or chemotherapy + mch1N11 groups. We showed that PS-targeting combined with standard CRT can significantly prolong survival in preclinical models of NSCLC and generate enhanced systemic anti-tumor immunity against lesions outside of the irradiated field. CRT up-regulated PD-L1 expression within the tumor and depleted tumor infiltrating cytotoxic CD8 T cells. The addition of mch1N11 antibody to CRT, however, was able to re-populate this critical immune effector cell population. Together, our results demonstrate that PS-targeting antibodies may be combined with CRT to enhance intrinsic tumor immunogenicity, activate systemic anti-tumor immune responses, and act as a priming strategy to sensitize the tumor to immune checkpoint inhibition with PD-1 or PD-L1 antibodies.

Improving homing in T cell therapy

Cytotoxic T lymphocytes (cytotoxic T cells, CTLs) are an immune effector cell population that can mediate specific immune responses against cancer. Based on this concept, tumor immunotherapy protocols have been developed using adoptive transfer of in vitro-expanded autologous T cells that can kill cancer cells. However, fully functional adoptive T cell therapies (ACT) are hampered by the inability to guarantee that all transferred T cells manage to reach the tumor sites and make contact with cancer cells. The lack of tumor homing of T cells may be caused by a variety of reasons. Stromal architecture and biological features of the tumor microenvironment may act as barriers to T cell migration. A mismatch between the chemokines released by the tumor or tumor stroma and the chemokine receptors expressed on the transferred T cells may also impede T cell homing. The identification of mechanisms responsible for cancer stroma remodeling is helping to overcome the barriers of access to tumors, via novel therapeutic strategies targeting tumor-stroma interactions. Simultaneously, recent studies have demonstrated ways through which virally-transduced CTLs can be made to express suitable chemokine receptors so as to enhance ACT, by improving CTL homing into the tumor. Here we review the most important findings related to T cell trafficking to the tumor, highlighting contributions that have led to promising improvements in the available T cell therapy strategies. We discuss new possible combinatorial strategies aimed to overcome chemokine mismatch, physical and biological barriers and immunosuppression, so as to achieve more effective ACT therapies.

APLIKASI METODE ADAMS BASHFORTH-MOULTON (ABM) PADA MODEL PENYAKIT KANKER

Cancer is a deadly disease that is characterized by the growth of abnormal cells, the growth is ongoing, forming a tumor. Tumors are divided into two parts, namely benign and malignant tumors. Malignant tumors are a general term for cancer. The disease of cancer has a mathematical model in the form of a system of differential equations, for it required a method to obtain the solution of the system of differential equations. The method used is the method of numerical methods Bashforth Adams Moulton (ABM) order one, two, three, and four. From the results of this study concluded that the method ABM order three better than the method ABM first order, second order and fourth order at issue models of cancer, It can be seen in the graphic simulation using ABM order three, it shows that increasing time population of immune effector cells (E) and a population of effector molecules (C) increased and then stabilized. The population of immune effector cells (E) stabilized at 33.3336, while the population of the effector molecule (C) is stable in the scope of the numbers 33,333, 33,333 are said to be in scope for changes in population effector molecule (C) can not be known with certainty. While the population of cancer cells (T) remains at 0 at each iteration (stable) remains in a state that is free of cancer

Pivotal Role for CD16+ Monocytes in Immune Surveillance of the Central Nervous System.

Monocytes represent a heterogeneous population of primary immune effector cells. At least three different subsets can be distinguished based on expression of the low-affinity FcγRIII: CD14(++)CD16 -: classical monocytes, CD14(++)CD16(+) intermediate monocytes, and CD14(+)CD16 ++: non-classical monocytes. Whereas CD16 -: classical monocytes are considered key players in multiple sclerosis (MS), little is known on CD16(+) monocytes and how they contribute to the disease. In this study, we examined the frequency and phenotype of monocyte subpopulations in peripheral blood, cerebrospinal fluid (CSF), and brain biopsy material derived from MS patients and controls. Furthermore, we addressed a possible monocyte dysfunction in MS and analyzed migratory properties of monocyte subsets using human brain microvascular endothelial cells. Our ex vivo studies demonstrated that CD16(+) monocyte subpopulations are functional but numerically reduced in the peripheral blood of MS patients. CD16(+) monocytes with an intermediate-like phenotype were found to be enriched in CSF and dominated the CSF monocyte population under noninflammatory conditions. In contrast, an inversed CD16(+) to CD16 -: CSF monocyte ratio was observed in MS patients with relapsing-remitting disease. Newly infiltrating, hematogenous CD16(+) monocytes were detected in a perivascular location within active MS lesions, and CD16(+) monocytes facilitated CD4(+) T cell trafficking in a blood -: brain barrier model. Our findings support an important role of CD16(+) monocytes in the steady-state immune surveillance of the CNS and suggest that CD16(+) monocytes shift to sites of inflammation and contribute to the breakdown of the blood-brain barrier in CNS autoimmune diseases.

Therapeutic efficacy of the F8-IL2 immunocytokine in a metastatic mouse model of lung adenocarcinoma.

Antibody-cytokine fusion proteins (immunocytokines) represent a novel class of armed antibodies in oncology. In particular, IL2- and TNF-based immunocytokines targeting the EDB domain of fibronectin and the A1 domain of tenascin-C have demonstrated promising anti-tumor activity and are currently investigated in Phase I and Phase II clinical trials. To advance the development of immunocytokines for NSCLC, we here report on the therapeutic efficacy of F8-IL2, an immunocytokine directed against the alternatively spliced EDA domain of fibronectin in a fully immunocompetent, orthotopic model of NSCLC, and the characterization of the target antigen expression in human NSCLC specimens. We evaluated the therapeutic efficacy of the F8-IL2 immunocytokine utilizing a K-ras mutant, p53 deficient metastatic mouse model of NSCLC derived from the latest generation of genetically engineered and conditional tumor models. In parallel, we assessed the presence of the EDA domain of fibronectin by immunofluorescence in lung biopsies obtained from patients with NSCLC. The EDA domain of fibronectin was broadly expressed in lung metastases obtained from our model. Treatment with F8-IL2 induced substantial local changes within immune effector cell populations and demonstrated promising therapeutic efficacy as monotherapy. The target of F8-IL2, the EDA domain of fibronectin, was present in all human lung adenocarcinoma specimens tested. Both the therapeutic efficacy in a metastatic mouse model of NSCLC and the extensive presence of the EDA domain of fibronectin in human NSCLC biopsies support the rational development of therapies based on the F8-IL2 immunocytokine for the treatment of NSCLC.

CCL27: Novel Cytokine with Potential Role in Pathogenesis of Multiple Sclerosis.

Multiple sclerosis (MS) is an autoimmune and neurodegenerative disease of unknown etiology. Leukocyte infiltration of brain tissue and the subsequent inflammation, demyelination, axonal damage, and formation of sclerotic plaques is a hallmark of MS. Upregulation of proinflammatory cytokines has been suggested to play an essential role in regulating lymphocyte migration in MS. Here we present data on serum cytokine expression in MS cases. Increased serum levels of IL-17 and IL-23 were observed, suggesting activation of the Th17 population of immune effector cells. Additionally, increased levels of IL-22 were observed in the serum of those with acute phase MS. Unexpectedly, we observed an upregulation of the serum chemokine CCL27 in newly diagnosed and acute MS cases. CCL27 is an inflammatory chemokine associated with homing of memory T cells to sites of inflammation. Therefore, its upregulation in association with MS suggests a potential role in disease pathogenesis. Our data supports previous reports showing IL-17 and -23 upregulation in association with MS and potentially identify a previously unknown involvement for CCL27.

Adoptive immunotherapy strategies with cytokine-induced killer (CIK) cells in the treatment of hematological malignancies.

Cytokine-induced killer (CIK) cells are a heterogeneous population of immune effector cells that feature a mixed T- and Natural killer (NK) cell-like phenotype in their terminally-differentiated CD3+CD56+ subset. The easy availability, high proliferation rate and widely major histocompatibility complex (MHC)-unrestricted antitumor activity of CIK cells contribute to their particularly advantageous profile, making them an attractive approach for adoptive immunotherapy. CIK cells have shown considerable cytotoxicity against both solid tumors and hematological malignancies in vitro and in animal studies. Recently, initial clinical experiences demonstrated the feasibility and efficacy of CIK cell immunotherapy in cancer patients, even at advanced disease stages. Likewise, the clinical application of CIK cells in combination with standard therapeutic procedures revealed synergistic antitumor effects. In this report, we will focus our consideration on CIK cells in the treatment of hematological malignancies. We will give insight into the latest advances and future perspectives and outline the most prominent results obtained in 17 clinical studies. Overall, CIK cells demonstrated a crucial impact on the treatment of patients with hematological malignancies, as evidenced by complete remissions, prolonged survival durations and improved quality of life. However, up to now, the optimal application schedule eventually favoring their integration into clinical practice has still to be developed.

Delayed emergency myelopoiesis following polymicrobial sepsis in neonates.

Neonates have increased susceptibility to infection, which leads to increased mortality. Whether or not this as a result of implicit deficits in neonatal innate immune function or recapitulation of innate immune effector cell populations following infection is unknown. Here, we examine the process of emergency myelopoiesis whereby the host repopulates peripheral myeloid cells lost following the initial infectious insult. As early inflammatory responses are often dependent upon NF-κB and type I IFN signaling, we also examined whether the absence of MyD88, TRIF or MyD88 and TRIF signaling altered the myelopoietic response in neonates to polymicrobial sepsis. Following neonatal polymicrobial septic challenge, hematopoietic stem cell (HSC) expansion in bone marrow and the spleen were both attenuated and delayed in neonates compared with adults. Similar reductions in other precursors were observed in neonates. Similar to adult studies, the expansion of progenitor stem cell populations was also seen in the absence of MyD88 and/or TRIF signaling. Overall, neonates have impaired emergency myelopoiesis in response to sepsis compared with young adults. Despite reports that this expansion may be related to TLR signaling, our data suggest that other factors may be important, as TRIF(-/-) and MyD88(-/-) neonatal HSCs are still able to expand in response to polymicrobial neonatal sepsis.

RANTES Promoter Gene Polymorphism and its Association with HBV Related Liver Disease

Background: Immune-mediated mechanisms have been found to play important role in the progression of hepatitis B virus (HBV) infection. Chemokines are a group of chemotactic molecules that specifically attract and recruit populations of immune effector cells to the sites of injury or infection. Their major role is in leukocyte migration and dependent processes such as immune surveillance and innate and adaptive immune responses. Regulated and normal T-cell expressed and secreted (RANTES) may have a role in the selective recruitment of T-cells to portal and periportal regions in liver during inflammation.