Mechanisms influencing natural killer cell recognition of tumour cells

Natural killer (NK) cells are part of our innate immune defence against virus-infected and transformed cells. Through a yet undefined mechanism, expression of inhibitory receptors for self-HLA class I molecules endow NK cells with increased functionality. The process leading to gain of function through inhibition is known as NK cell education. In the first part of this thesis the cellular mechanisms behind this phenomenon were studied. We found that the expression levels of the activation/adhesion molecule DNAM-1 correlated with the education state in NK cells. Our results suggest that DNAM-1 together with coordinated conformational changes in the adhesion molecule LFA-1 may contribute to the heightened effector functions in educated NK cells. A decreased NK cell function has been previously associated with impaired immune surveillance and a higher risk for developing cancer. By studying samples from patients diagnosed with myelodysplastic syndromes (MDS), we found that NK cells in the bone marrow were phenotypically altered and functionally impaired. Two activating receptors, DNAM-1 and NKG2D were decreased, and the ability to recognise and kill MDS blast cells compromised. The phenotypic alterations correlated with the frequency of leukemic blast cells suggesting that the immune dysfunction progress with the severity of the disease. In one part of this thesis possibilities to improve tumour cell recognition by NK cells were examined. Oxidative stress induced by selenite in a tumour cell line lowered the surface expression of HLA-E, which is a ligand for inhibitory NKG2A receptors expressed by a large proportion of human NK cells. The downregulation of HLA-E led to increased NK cell detection and killing of the tumour cells by NKG2A+ NK cells. Therapeutic antibodies have led to a paradigm shift in the care of patients with malignant lymphoma. Yet the mechanisms of action and the contribution of discrete immune subsets to the clinical efficacy are largely unknown. One suggested mechanism is NK cell mediated antibody-dependent cellular cytotoxicity. We studied NK cell repertoires in sequential lymph node biopsies from follicular lymphoma patients undergoing treatment with anti-CD20 antibodies. After treatment there was a decrease in peripheral NK cells, and the remaining NK cells from both peripheral blood and tumour-associated lymph nodes were activated. Furthermore, the NK cells showed an altered ability to produce cytokines after in vitro restimulation. In conclusion, the data presented here provide new insights into how NK cells recognise and respond to tumour cells at steady state and in malignant diseases

Systemic and Intra-Nodal Activation of NK Cells After Rituximab Monotherapy for Follicular Lymphoma

Monotherapy with the anti-CD20 monoclonal antibody rituximab can induce complete responses (CR) in patients with follicular lymphoma (FL). Resting FcRγIII+ (CD16+) natural killer (NK) cells respond strongly to rituximab-coated target cells in vitro. Yet, the contribution of NK cells in the therapeutic effect in vivo remains unknown. Here, we followed the NK cell repertoire dynamics in the lymph node and systemically during rituximab monotherapy in patients with FL. At baseline, NK cells in the tumor lymph node had a naïve phenotype albeit they were more differentiated than NK cells derived from control tonsils as determined by the frequency of CD56dim NK cells and the expression of killer cell immunoglobulin-like receptors (KIR), CD57 and CD16. Rituximab therapy induced a rapid drop in NK cell numbers coinciding with a relative increase in the frequency of Ki67+ NK cells both in the lymph node and peripheral blood. The Ki67+ NK cells had slightly increased expression of CD16, CD57 and higher levels of granzyme A and perforin. The in vivo activation of NK cells was paralleled by a temporary loss of in vitro functionality, primarily manifested as decreased IFNγ production in response to rituximab-coated targets. However, patients with pre-existing NKG2C+ adaptive NK cell subsets showed less Ki67 upregulation and were refractory to the loss of functionality. These data reveal variable imprints of rituximab monotherapy on the NK cell repertoire, which may depend on pre-existing repertoire diversity

Att få dö i trygga händer - en handlingsplan för palliativ vård

Examensarbetet ”Att få dö i trygga händer” är ett beställningsarbete från två vårdavdelningar i Österbotten. Respondenterna har tillsammans med vårdpersonal, en expertgrupp, utformat en handlingsplan för palliativ vård. Syfte med detta examensarbete är att beskriva en värdig omvårdnad för patienter i livets slutskede. Hur kan smärta ta sig i uttryck hos den döende patienten samt hur kan vi som vårdpersonal identifiera och lindra smärta, är frågeställningar som respondenterna utgått ifrån. Även stödet till de närstående har lyfts fram. Data insamlades med hjälp av fokusintervjuer och innehållsanalys användes för att analysera materialet. Resultatet tolkades mot teoretisk referensram, där respondenterna utgått från Eriksons syn på lidande och hopp samt Hendersons behovsteori och hennes antaganden om att kropp och själ är oskiljaktiga och att patienten och familjen är en enhet. Resultaten tolkades även mot teoretisk bakgrund, hospice vårdideologi och smärta som begrepp, samt tidigare forskningar. Resultatet i studien visar att smärta är ett mångfacetterat problem och ett vanligt symtom hos patienter i livets slutskede. Av vårdpersonal krävs kreativa tillvägagångssätt för att förstå, bedöma och hantera smärta hos denna patientgrupp. All smärta kan inte lindras med hjälp av läkemedel. Goda samtal har en läkande verkan och lindrar lidande.The study “Dying in safe hands” was initialized and ordered by two hospital wards in the Ostrobothnia region. As a result of the study, an action plan for terminal care has been designed, in co-operation with an expert group from the hospital wards. The aim of this study is to describe care of the dying patients that focuses on dignity. The study was conducted to determine how patients experience pain, as well as means by which care workers can identify and relieve pain. Also support to the patients family members, is discussed. Data was collected through focus interviews and content analysis was used to analyze the material. The result of the study was interpreted within a theoretical frame of reference, such as Erikson´s theory of suffering and hope and Henderson´s Need Theory and her assumes that mind and body are inseparable and that patients and their families should be seen as a whole. The interpretations were also based on the hospice care ideology and the concept of pain as well as earlier research. The result of this study shows that pain is a multifaceted problem and a common symptom among patients in the final stages of life. Care workers are required to use creative methods to understand, assess and manage pain within this group of patients. Result show that medicine alone is not sufficient in enabling patients to be comfortable and free of pain. Good conversations between health professionals and the patients and their families are a healing experience and alleviate suffering.Tutkielma, ”Saada kuolla hyvissä käsissä” on tilaustyö kahdelta hoito-osastolta Pohjanmaalta. Respondentit ovat yhdessä hoitohenkilökunnan kanssa, niin sanotun erikoisryhmän kanssa, kehittäneet toimintasuunnitelman palliatiiviseen hoitovaiheeseen. Tämän tutkielman tarkoitus on kuvata arvokkaan hoidon potilaalle elämän loppuvaiheessa. Miten voidaan kipu määritellä kuolevalla potilaalla ja kuinka voimme hoitajana tunnistaa ja lievittää kipua ovat kysymyksiä mihin respondentit ovat keskittyneet. Myös tuki läheisille on nostettu esille. Tiedot kerättiin keskitettyjen haastattelujen avulla jotka myöhemmin analysoitiin sisällönanalyysin mukaan. Tulokset tulkittiin teoreettiseen viitekehykseen, alkaen Erikssonin näkemys kärsimyksestä ja toivosta sekä Hendersonin tarveteoria, hänen oletuksia että mieli ja keho ovat erottamattomia ja että potilas ja perhe on yksikkö. Tulokset tulkittiin myös teoreettisen taustan, saattohoidon ideologian ja kipu käsitteenä, sekä aiempien tutkimuksien avulla. Tutkimuksen tulos osoitti, että kipu on monimuotoinen ongelma ja on tavallinen oire potilailla elämän loppuvaiheessa. Hoitohenkilökunnalta vaaditaan luovia lähestymistapoja jotta voisivat ymmärtää, arvioida ja käsitellä kipua tällä potilasryhmällä. Kaikkia kipuja ei voi lievittää lääkkeillä. Hyvällä keskustelulla on parantava vaikutus ja se lieventää kipua

Maintaining doubt to keep problems open for exploration: An analysis of law students' collaborative work with case assignments

This article examines how second-year law students act and interact to maintain legal doubt in solving case assignments in groups. Professional norms of inquiry within the legal domain include keeping an issue open for exploration and ensuring that all potentially relevant aspects of a case are considered before reaching a conclusion, as well as making the basis for such conclusions transparent. However, we do not know much about how students appropriate this core aspect of legal problem-solving. We analysed videotaped discussions in two student groups as they worked with cases in international law. The findings bring to the fore how (1) the students' interactions; (2) legal texts; and (3) the use of professional procedures and principles for investigation constituted an exploratory dynamic through which doubt was collectively produced and maintained in the group work. The analysis shows that in the process of getting deeper into aspects of the case at hand, problems where opened up and kept open by the students'/construction of a number of intermediate questions. The relevance of such questions was tested in the group work, but also guided by texts and procedures that are linked in systematic ways. The article argues for the value of group work to support students in learning to take part in core knowledge practices that characterize legal problem-solving