Inflammatory cytokines and their receptors in psoriatic skin : emphasis on the epidermal interleukin 1 system

Nearly two centuries have passed since the first accurate description of psoriasis by Wilan in the year 1808. Psoriasis is a common, well-defined skin disease featuring the interplay of genetic, environmental, and immunological factors. Extensive reviews on psoriasis are given elsewhere. Despite numerous reports, the exact etiology is still unknown. Moreover, 70 % of psoriatic patients are not satisfied with the currently available anti-psoriatic treatments (Gottlieb AB, oral presentation, Psoriasis Meeting, Dec 4-5 1995, Lake Buena Vista, FL), which stresses the contemporary societal interest of psoriasis research. Recent studies have identified a dysregulated crosstalk between resident skin cells and infiltrating leukocytes in psoriasis. Several lines of evidence point to the cytokine interleukin 1 (IL-l) as an integral component of the cellular immune basis of psoriasis. The regulation of cytokine activity in general, and that of epidermal IL-l in particular, is described in chapter 1.1. Skin as a site of immune responses, exemplified by the cutaneous inflammatory response, is described in chapter 1.2. Finally, the cellular immunopathogenesis of psoriasis, with special emphasis on IL-l, is reviewed in chapter 1.3

Identification of the het-r vegetative incompatibility gene of Podospora anserina as a member of the fast evolving HNWD gene family

In fungi, vegetative incompatibility is a conspecific non-self recognition mechanism that restricts formation of viable heterokaryons when incompatible alleles of specific het loci interact. In Podospora anserina, three non-allelic incompatibility systems have been genetically defined involving interactions between het-c and het-d, het-c and het-e, het-r and het-v. het-d and het-e are paralogues belonging to the HNWD gene family that encode proteins of the STAND class. HET-D and HET-E proteins comprise an N-terminal HET effector domain, a central GTP binding site and a C-terminal WD repeat domain constituted of tandem repeats of highly conserved WD40 repeat units that define the specificity of alleles during incompatibility. The WD40 repeat units of the members of this HNWD family are undergoing concerted evolution. By combining genetic analysis and gain of function experiments, we demonstrate that an additional member of this family, HNWD2, corresponds to the het-r non-allelic incompatibility gene. As for het-d and het-e, allele specificity at the het-r locus is determined by the WD repeat domain. Natural isolates show allelic variation for het-

Enhanced recruitment of genetically modified CX3CR1-positive human T cells into Fractalkine/CX3CL1 expressing tumors: importance of the chemokine gradient.

BACKGROUND: Adoptive T-cell based immunotherapies constitute a promising approach to treat cancer, however, a major problem is to obtain effective and long-lasting anti-tumor responses. Lack of response may be due to insufficient trafficking of specific T cells to tumors. A key requirement for efficient migration of cytotoxic T cells is that they express chemokine receptors that match the chemokines produced by tumor or tumor-associated cells. METHODS: In this study, we investigated whether the in vivo tumor trafficking of activated T cells could be enhanced by the expression of the chemokine receptor CX3CR1. Two human colorectal cancer cell lines were used to set up a xenograft tumor model in immunodeficient mice; the NCI-H630, constitutively expressing the chemokine ligand CX3CL1 (Fractalkine), and the RKO cell line, transduced to express CX3CL1. RESULTS: Human primary T cells were transduced with the receptor CX3CR1-eGFP. Upon in vivo adoptive transfer of genetically modified CX3CR1-T cells in mice bearing NCI-H630 tumors, enhanced lymphocyte migration and tumor trafficking were observed, compared to mice receiving Mock-T cells, indicating improved homing ability towards ligand-expressing tumor cells. Furthermore, significant inhibition of tumor growth was found in mice receiving modified CX3CR1-T cells. In contrast, tumors formed by RKO cells transduced with the ligand (RKO-CX3CL1) were not affected, nor more infiltrated upon transfer of CX3CR1-T lymphocytes, likely because high levels of the chemokine were shed by tumor cells in the systemic circulation, thus nullifying the blood-tissue chemokine gradient. CONCLUSIONS: This study demonstrates that ectopic expression of CX3CR1 enhanced the homing of adoptively transferred T cells towards CX3CL1-producing tumors, resulting in increased T cell infiltration in tumor tissues and decreased tumor growth. Our results also establish that a correct chemokine gradient between the systemic circulation and the tumor is an essential requirement in adoptive T-cell based immunotherapy to efficiently recruit T cell effectors at the correct sites

Treatment of cervicofacial actinomycosis: a report of 19 cases and review of literature

Objectives: Actinomycosis is a chronic suppurative granulomatous infection caused by the Actinomyces genus. Orocervicofacial actinomycosis is the most common form of the disease, seen in up to 55% of cases. All forms of actinomycosis are treated with high doses of intravenous penicillin G over two to six weeks, followed by oral penicillin V. Large studies on cervicofacial actinomycosis are lacking. Therefore proper guidelines for treatment and treatment duration are difficult to establish. The aim of this study is to establish effective treatment and treatment duration for orocervicofacial actinomycosis. Study design: A Pubmed and Embase search was performed with the focus on treatment and treatment duration for cervicofacial actinomycosis. The hospital records of all patients presenting to our department with head and neck infection from January 2000 to December 2010 were reviewed, retrospectively. The following data were collected: age, gender, clinical presentation, aetiology, duration of symptoms, microbiological findings, treatment, and duration of treatment. The treatment and treatment duration is subsequently compared to the literature. Results: The literature search provided 12 studies meeting the inclusion criteria. All studies were retrospective in nature. Penicillin or amoxicillin/clavulanic acid are the preferred antibiotic regimens found in the literature. Most of our patients were treated with a combination of penicillin G 12 million units/day and metronidazol 500 mg 3/ day, most commonly for a duration of 1 - 4 weeks, being shorter than the 3 - 52 weeks reported in the literature. Conclusion: When actinomycosis is suspected, our review has shown that a surgical approach in combination with intravenous penicillin and metronidazol until clinical improvement is seen, followed by oral antibiotics for 2 - 4 weeks is generally efficient

T cell retargeting with MHC class I-restricted antibodies: the CD28 costimulatory domain enhances antigen-specific cytotoxicity and cytokine production

T cells require both primary and costimulatory signals for optimal activation. The primary Ag-specific signal is delivered by engagement of the TCR. The second Ag-independent costimulatory signal is mediated by engagement of the T cell surface costimulatory molecule CD28 with its target cell ligand B7. However, many tumor cells do not express these costimulatory molecules. We previously constructed phage display derived F(AB), G8, and Hyb3, Ab-based receptors with identical specificity but distinct affinities for HLA-A1/MAGE-A1, i.e., "TCR-like" specificity. These chimeric receptors comprised the FcepsilonRI-gamma signaling element. We analyzed whether linking the CD28 costimulation structure to it (gamma + CD28) could affect the levels of MHC-restricted cytolysis and/or cytokine production. Human scFv-G8(POS) T lymphocytes comprising the gamma + CD28 vs the gamma signaling element alone produced substantially more IL-2, TNF-alpha, and IFN-gamma in response to HLA-A1/MAGE-A1(POS) melanoma cells. Also a drastic increase in cytolytic capacity of scFv-G8(POS) T cells, equipped with gamma + CD28 vs the gamma-chain alone was observed

T Cell Maturation Stage Prior to and During GMP Processing Informs on CAR T Cell Expansion in Patients

textabstractAutologous T cells were genetically modified to express a chimeric antigen receptor (CAR) directed toward carboxy-anhydrase-IX (CAIX) and used to treat patients with CAIX-positive metastatic renal cell carcinoma. In this study, we questioned whether the T cell maturation stage in the pre-infusion product affected CAIX CAR expression and function in vitro as well as in vivo CAR T cell numbers and expansion. During the 14 days expansion of CAR T cells prior to administration, we observed shifts from a predominant CD4 to a CD8 T cell phenotype and from a significant fraction of naïve to central effector T cells. Surface expression of the CAR was equally distributed among different T cell subsets and T cell maturation stages. During T cell culture days 14-18 (which covered patient treatment days 1-5), T cells demonstrated a decline in CAR expression level per cell irrespective of T cell maturation stage, although the proportion of CAR-positive T cells and CAR-mediated T cell effector functions remained similar for both CD4 and CD8 T cell populations. Notably, patients with a higher fraction of naïve CD8 T cells at baseline (prior to genetic modification) or central effector CD8 T cells at 2 weeks of CAR T cell culture demonstrated a higher fold expansion and absolute numbers of circulating CAR T cells at 1 month after start of therapy. We conclude that the T cell maturation stage prior to and during CAR T cell expansion culture is related to in vivo CAR T cell expansion

T cell receptor fused to CD3ζ: Transmembrane domain of CD3ζ prevents TCR mis-pairing, whereas complete CD3ζ directs functional TCR expression

TCR gene therapy represents a feasible and promising treatment for patients with cancer and virus infections. Currently, this treatment rationale is hampered by diluted surface expression of the TCR transgene and generation of potentially self reactive T-cells, both a direct consequence of mis-pairing with endogenous TCR chains. As we reported previously (Gene Ther 16:1369, 2000; J Immunol 180:7736, 2008), TCR mis-pairing can be successfully addressed by a TCR:CD3ζ fusion protein (i.e., TCR:ζ). Here, we set out to minimize the content of CD3ζ in TCR:ζ, specific for MAGEA1/ HLA-A1, without compromising TCR pairing and function. Domain-exchange and 3D-modeling strategies defined a set of minimal TCR:ζ variants, which, together with a murinized and cysteine-modified TCR (TCR:mu+cys), were tested for functional TCR expression and TCR pairing. Our data with Jurkat T cells show that the CD3ζ transmembrane domain is important for cell-surface expression, whereas the CD3ζ intracellular domain is crucial for T-cell activation. Notably, inability of TCR:ζ to mis-pair was not observed for TCR:mu+cys, which depended exclusivel

Enhanced recruitment of genetically modified CX3CR1-positive human T cells into Fractalkine/CX3CL1 expressing tumors: Importance of the chemokine gradient

Background: Adoptive T-cell based immunotherapies constitute a promising approach to treat cancer, however, a major problem is to obtain effective and long-lasting anti-tumor responses. Lack of response may be due to insufficient trafficking of specific T cells to tumors. A key requirement for efficient migration of cytotoxic T cells is that they express chemokine receptors that match the chemokines produced by tumor or tumor-associated cells. Methods: In this study, we investigated whether the in vivo tumor trafficking of activated T cells could be enhanced by the expression of the chemokine receptor CX3CR1. Two human colorectal cancer cell lines were used to set up a xenograft tumor model in immunodeficient mice; the NCI-H630, constitutively expressing the chemokine ligand CX3CL1 (Fractalkine), and the RKO cell line, transduced to express CX3CL1. Results: Human primary T cells were transduced with the receptor CX3CR1-eGFP. Upon in vivo adoptive transfer of genetically modified CX3CR1-T cells in mice bearing NCI-H630 tumors, enhanced lymphocyte migration and tumor trafficking were observed, compared to mice receiving Mock-T cells, indicating improved homing ability towards ligand-expressing tumor cells. Furthermore, significant inhibition of tumor growth was found in mice receiving modified CX3CR1-T cells. In contrast, tumors formed by RKO cells transduced with the ligand (RKO-CX3CL1) were not affected, nor more infiltrated upon transfer of CX3CR1-T lymphocytes, likely because high levels of the chemokine were shed by tumor cells in the systemic circulation, thus nullifying the blood-tissue chemokine gradient. Conclusions: This study demonstrates that ectopic express