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

The Impact of Leprosy on Marital Relationships and Sexual Health among Married Women in Eastern Nepal

Background. Leprosy is one of the most stigmatized diseases known today. The stigma surrounding leprosy can be a major burden and affects many dimensions of a person’s life, including intimate relationships. We aimed to investigate the experiences of women affected by leprosy regarding marital life and sexuality, comparing these to the experiences of women with other physical disabilities and to those of able-bodied women in South-East Nepal. Methods. This study used a qualitative approach and a cross-sectional, nonrandom survey design. Thirty women underwent in-depth interviews about their marital and sexual relationship by means of a semi-structured interview guide. These thirty women included ten women affected by leprosy, ten women with other physical disabilities, and ten able-bodied women living in South-East Nepal. Results. We found that many women faced violence and abuse in their marriages. However, women affected by leprosy appeared to face more problems with regard to their marital and sexual relationships than women with physical disabilities and able-bodied women. Some of these related to the fear of leprosy. Conclusions. Further research is recommended to investigate the extent of this problem and ways to ameliorate the situation of the affected women. Education and counselling at diagnosis may help prevent many of the problems reported

Oplossingen om de 30%-kortingsregeling te realiseren (2)

Met ingang van 1 januari 1995 is de 30%-kortingsregeling op de niet-grondgebonden mestproductierechten ingegaan. Met name hoogproductieve zeugenbedrijven zullen ingrijpende maatregelen moeten treffen om aan deze regeling te kunnen voldoe

Financiele ruimte voor de bewerking van zeugenmest

Er bestaan veel vragen over de haalbaarheid van bewerking van dunne mest op boerderijniveau. Het Praktijkonderzoek Varkenshouderij onderzoekt in samenwerking met de Cehave hoe hoog de jaarkosten voor mestbewerking in verschillende praktijksituaties mogen zijn

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