Clinical characteristics of idiosyncratic drug reactions (IDRs) suggest that they are immune mediated. Penicillamine-induced autoimmunity in Brown Norway rats was used as a tool for mechanistic studies of this type of IDR. It has been shown that T helper 17 (Th17) cells play a central role in many types of autoimmune diseases. This study was designed to test whether Th17 cells are involved in the pathogenesis of penicillamine-induced autoimmunity. In sick animals, interleukin (IL) 6 and transforming growth factor-β1, known to be driving forces of Th17 differentiation, were consistently increased following penicillamine treatment. IL-17 and IL-22, characteristic cytokines produced by Th17 cells, were increased in sick animals. Furthermore, the percentage of IL-17-producing CD4 T cells was significantly increased, but only in sick animals. Retinoic acid, which has been reported to inhibit Th17 cell development, made the autoimmunity worse, increased IL-6 production, and did not decrease the number of Th17 cells. An infiltration of CD8 cytotoxic T cells in the liver suggests that they may be the key player in causing liver toxicity induced by D-penicillamine. Drug-induced liver injury (DILI) is one of the major causes of morbidity, mortality, and drug candidate failure. Recently, it has been suggested that Th17 cells may play an active role in inflammatory human liver diseases. In a study of patients being treated with isoniazid, some patients developed mild liver injury. The percentage of Th17 cells in the blood of these patients significantly increased when the ALT increased, and this suggests that they play a role in the mechanism of this liver injury. Furthermore, IL-10-producing T cells also increased and this may have prevented the development of severe liver injury. In another study, two hours after treatment of mice with acetaminophen there was a significant increase in Th17 cells in the liver. This rapid response suggests that Th17 cells can be part of the innate immune response to liver injury. Our data provided evidence that Th17 cells are involved in both “toxic” and idiosyncratic liver toxicity. This pathway could be a new target for the therapeutic interventions to treat DILI.

The pathology of multiple sclerosis (MS) is characterized by an inflammatory mononuclear infiltration in the white matter. There has been converging evidence of the oxidative stress playing a role in the onset and progression of MS. We postulated that the decreasing oxidative stress might help in the management of MS. We know that the induction of phase 2 enzymes decreases the oxidative stress. The experimental allergic encephalomyelitis (EAE) induced in the Lewis rats were used to test this hypothesis. The 24 animals were placed into two groups: 1) those on normal rat chow, 2) those on rat chow containing 7.5 g/kg of tetra-butylhydroxyanisole (BHA), a food preservative. All the animals were administered 100 µg of guinea pig myelin basic protein in their tails to induce EAE and examined daily in a double blinded fashion. On 29th day of the induction, the animals were sacrificed, blood collected for glutathione (GSH) measurements and tissues collected for histology. All the animals, regardless of their diet status, developed symptoms of EAE on different days ranging from tail weakness to hind limb paralysis and all of them reached remission of acute EAE before the 28th day of induction. The non-BHA fed animals developed hind limb weakness in 8 animals and hind limb paralysis in 4 cases, while that of BHA fed group developed tail paralysis in 2, hind limb weakness in 2 and hind limb paralysis in 8 cases. The histology of the non-BHA group correlated well with the clinical symptoms of perivascular mononuclear infiltration. However, the BHA group revealed complete pathological recovery. Animals with BHA in the diet had significantly raised GSH, indicating the induction of phase 2 enzymes. We conclude that dietary phase 2 enzyme inducers show potential therapeutic benefits in EAE and should be examined for this role in MS.

Clinical characteristics of idiosyncratic drug reactions (IDRs) suggest that they are immune mediated. Penicillamine-induced autoimmunity in Brown Norway rats was used as a tool for mechanistic studies of this type of IDR. It has been shown that T helper 17 (Th17) cells play a central role in many types of autoimmune diseases. This study was designed to test whether Th17 cells are involved in the pathogenesis of penicillamine-induced autoimmunity. In sick animals, interleukin (IL) 6 and transforming growth factor-β1, known to be driving forces of Th17 differentiation, were consistently increased following penicillamine treatment. IL-17 and IL-22, characteristic cytokines produced by Th17 cells, were increased in sick animals. Furthermore, the percentage of IL-17-producing CD4 T cells was significantly increased, but only in sick animals. Retinoic acid, which has been reported to inhibit Th17 cell development, made the autoimmunity worse, increased IL-6 production, and did not decrease the number of Th17 cells. An infiltration of CD8 cytotoxic T cells in the liver suggests that they may be the key player in causing liver toxicity induced by D-penicillamine. Drug-induced liver injury (DILI) is one of the major causes of morbidity, mortality, and drug candidate failure. Recently, it has been suggested that Th17 cells may play an active role in inflammatory human liver diseases. In a study of patients being treated with isoniazid, some patients developed mild liver injury. The percentage of Th17 cells in the blood of these patients significantly increased when the ALT increased, and this suggests that they play a role in the mechanism of this liver injury. Furthermore, IL-10-producing T cells also increased and this may have prevented the development of severe liver injury. In another study, two hours after treatment of mice with acetaminophen there was a significant increase in Th17 cells in the liver. This rapid response suggests that Th17 cells can be part of the innate immune response to liver injury. Our data provided evidence that Th17 cells are involved in both “toxic” and idiosyncratic liver toxicity. This pathway could be a new target for the therapeutic interventions to treat DILI.

Chaperonin 10 (Cpn10) is a mitochondrial protein with protein folding function. There is substantial evidence that extracellular Cpn10 regulates the immune response. Prior research has shown that Cpn10 binds to T cells, inhibits LPS-induced RAW264.7 macrophage cell- and healthy donor peripheral blood mononuclear cell (PBMC)-activation, and downregulates lipopolysaccharide (LPS)-induced membrane distribution of the MHC II molecule on dendritic cells (DC). Recent Phase IIa rheumatoid arthritis (RA), psoriasis and multiple sclerosis (MS) clinical trials demonstrate improved disease amelioration with Cpn10. Despite compelling evidence of the anti-inflammatory properties of Cpn10, the precise mechanisms of action are unknown. The principal aim was to characterise the modulation of inflammation by Cpn10 and in the process create a bioassay that would allow for the reliable assessment of batch-to-batch variability of Cpn10 preparations. For this purpose, a Cpn10 bioassay was performed in the RAW264.7 cell line and expanded to DC and T cell lines. Furthermore, the analysis of gene expression in healthy donor PBMC was performed, as a mixed cell population experiment, to reflect possible involvement of cell-to-cell communication pathways. Initial data showed that Cpn10 reduced LPS-induced tumour necrosis factor ?? (TNF??) expression in RAW264.7 cells. However, the Cpn10 preparation was shown to contain trace lipid contaminants, which induced cellular tolerance, resulting in the observed reduction in TNF??. Experiments with a second batch of Cpn10 showed no reduction of LPS-induced TNF?? in the RAW264.7 cells, seen with the primary batch of Cpn10 and previously reported characterisation of Cpn10. The Cpn10 bioassay conducted in DC and T cell lines was shown to have the potential to decrease toll-like receptor 9 (TLR9) expression, suggesting that Cpn10 may attenuate immune responses by downregulating receptor recognition of bacterial components. The Cpn10 bioassay conducted in LPS-stimulated PBMCs revealed that Cpn10 downregulates gene expression of Th1 related genes including the polarising cytokines IL-7, IL-12B and IL-23A and Th2 related genes including the transcriptions factors GATA3, GFI1 and CEBPB. The downregulation of these genes may play an immuno-modulatory role, having improved efficacy of Cpn10 in T cell mediated autoimmune diseases, with possible therapeutic implications in Th2 mediated diseases such as asthma. The research carried out in this thesis provides insight into the success of Cpn10 in the RA, MS and psoriasis clinical trials. These results have also supported previously published data and provide additional insight into the mechanism of action of Cpn10. In addition, a Cpn10 bioassay has been established using healthy donor PBMCs stimulated with LPS and results show a reduced expression of Th1 and Th2 associated genes. The findings that in mixed cell populations, Cpn10 downregulates not only genes involved in Th1 polarisation mainly at the signal 3 level, but is also capable of downregulating Th2 polarising genes at the signal 1 level of TCR mediated transcription factors, are of particular interest. Ultimately, research from this project has confirmed the anti-inflammatory action of Cpn10 and given useful insight into how Cpn10 acts to modulate the inflammatory response.

Cette réflexion est l'aboutissement d'une pratique salariale dans le monde du handicap et de la dépendance. Mon terrain clinique partira de mon travail comme psychologue clinicien sur deux EHPAD (un établissement public et un autre privé). Le regard porté sur cette nouvelle population que certains nomment « adulte dépendant » change selon la place que nous occupons. J'ai proposé dans ce travail de recherche en anthropologie de rapprocher la question du vieillissement à celle du handicap. Si de nombreux discours se côtoient, une nouvelle catégorie semble voir le jour : celle de l'aidant qui est souvent le (la) seul(e) personne en prise directe à domicile. En EHPAD, un accompagnement est également nécessaire car ces aidants ont souvent une charge de travail, en tant que non professionnels, qui est peu perçue. Tout se joue dans l'accompagnement possible entre se substituer à l'aidant et accompagner ce dernier dans un « faire avec » qui permettra de pallier ses manquements dus à ses propres pertes. Mes questionnements anthropologiques m'ont amené à interroger les mots du contemporain qui, même s’ils ne sont pas propres à mon objet d’étude, sont néanmoins essentiels pour penser notre monde. Ces mots sont : la « dépendance », la « vieillesse » et le « handicap » auxquels s'ajoutent « la mort, le travail, la mémoire et la sexualité ». Au-delà des différents discours tenus autour de la dépendance, on retrouve surtout des enjeux de pouvoir. Pouvoir politique mais également médical ou encore associatif sans oublier le pouvoir sur soi. Je propose en guise d'ouverture en conclusion de développer cette question des pouvoirs. / This reflection is the outcome of a wage practice in the world of the handicap and the dependence. My clinical ground will leave my work as psychologist clinician on two EHPAD (a public institution and one other deprived). The look concerned this new population which some name " dependent adult " changes according to the place which we occupy. I suggested in this research work in anthropology moving closer to the question of the ageing to that of the handicap.If numerous speeches mix, a new category seems to be born: that of the helper who is often only person acting at home. In EHPAD, a accompaniment is also necessary because these helpers often have a workload, as not professionals, which is little perceived. Everything takes place in the possible accompaniment to substitute itself for the helper and accompany the latter in one " to make with " whom will allow to mitigate his negligences due to his (her) own losses. My anthropological questionings brought me to question the words of the contemporary which, even if they are not appropriate to my object of study, are nevertheless essential to think of our world. These words are: the "dependence", the "old age" and the "handicap" to whom are added " the death, the work, the memory and the sexuality ". Beyond the various speeches held around the dependence, we find especially stakes in power. Political but also medical or still associative power without forgetting the power on one. I propose by way of opening to develop this question of the powers.

Humoral immunity provides protection against subsequent infections. Antigen-specific, high-affinity, class-switched antibodies are produced by B cells through rounds of proliferation, B cell receptor rearrangement and selection in the germinal centres (GC). T cells play an essential and indispensable role in this process and in the recent years the term T follicular helper cells (TFH) was coined to describe this cell subset. The aim of my thesis is to investigate whether there is more than one type of T cells within the TFH population and whether it has important functional consequences. Firstly, I use sheep red blood cell immunisation (SRBC) and Salmonella enterica infection to show phenotypical differences between TFH expressing high and low level of surface molecule PD-1. In order to investigate the relationship between different TFH populations gene profiling was carried out on the microarray platform. Detailed transcriptome analysis revealed the discrete nature of isolated TFH cell subsets and provided an overview of their genetic landscape. Secondly, I have investigated the dependence of TFH subsets on cognate interactions with B cell in SRBC model by generating BM chimeras. I have demonstrated that generation of PD-1HI TFH, but not of PD-1LO TFH, depends on antigen presentation by B cells. Furthermore, I have shown that provision of wild-type but not MHC II knock-out B cells rescues PD-1HI formation in BM chimeras after SRBC immunisation. Finally, I have explored plasticity within TFH subsets and showed that none of the populations is in a terminally differentiated state, as they can convert into one another. Thirdly, experiments with S. enterica model revealed that the absence of PD- 1HI TFH is independent of the splenic architecture disruption present within the first week of the response. Surprisingly, co-immunisation studies showed that PD-1HI population is not only present but even enhanced in the group which received both SRBC and S. enterica when compared to single immunisations. The work presented in the thesis documents that there is a significant and previously unappreciated heterogeneity within TFH subset. This knowledge is important for designing optimal vaccine strategies and treating autoimmune diseases, as in both processes the antibody production plays a crucial role and its manipulation (either enhancing or blocking antibody production, respectively) can significantly improve clinical interventions.

When injected with live P815 tumour cells, DBA/2 mice developed cytotoxic cells reactive to the tumour. In addition, T helper cells from tumour-bearing mice enhanced the iri vitro generation of cytotoxic cells from normal DBA/2 spleen cells. The helper cells had the following properties (1) expression of the Thy-1.2 antigen; (2) resistance to y-radiation; (3) specific enhancement of the cytotoxic response to P815; (4) detectability in P815-bearing mice at the peak of cytotoxic cell activity; (5) activity in the early phase of cytotoxic cell activation. In parallel to the development of helper cell activity, suppressor cells were generated which suppressed the cytotoxic response to P815. These suppressor cells were removed by pre-treating mice with low doses of cyclophosphamide. High doses of cyclophosphamide reduced the cytotoxic response to both P815 and C57B1/6 alloantigens. Cyclophosphamide treatment reduced the frequency of cytotoxic precursor cells directed against P815, and an antigen-reactive helper cell involved in interleukin 2 production. Both interleukin 2 and thymocytes from P815-primed mice, restored the cytotoxic response against P815, to normal levels. Twenty six percent of animals primed with tumour cells cleared a challenge dose of P815 faster than unprimed control mice. Of these, 88% survived longer than the control animals. Eighteen percent of the recipients of cells from tumour-primed mice, cleared a challenge dose of P815 faster than mice injected with normal cells. Of these 53% survived significantly longer than control groups given either normal cells or no cells at all. Cells from mice primed to PPD showed significantly enhanced proliferative responses to soluble and P815-bound PPD, when compared with unprimed animals. However, cells from only a few PPD-primed mice showed enhanced cytotoxicity against P815 tumour cells, and PPD-primed cells either did not alter, or suppressed, the cytotoxic response of normal DBA/2 spleen cells, when stimulated with PPD-coated P815. / Science, Faculty of / Microbiology and Immunology, Department of / Graduate

Deoxyribonucleic acid isolated from bacteriophage lambda can infect Escherichia coli K12 in the presence of adsorbed helper phage (Kaiser and Hogness, 1960; Kaiser, 1962). The manner in which lambda DNA enters the cell and the possible role of helper phage in the penetration process is still not clear. Kinetic studies conducted in this laboratory during the initial stages of infection by lambda DNA demonstrate a requirement for helper function during the penetration of an infectious molecule. Further investigation into this problem is needed and was the major objective of this study.

Volunteering has been demonstrated to increase various outcomes of health and well-being. However, it has not been utilized as a therapeutic tool for transitional aged youth (TAY), who demonstrate disparate outcomes in various areas of health and well-being. The author hypothesizes that engaging in volunteering with application of the “8 C’s” framework will lead to improved well-being and empowerment. The author designed We Rise by Lifting Others (WRBLO), a nine-week program to engage TAY in volunteering while incorporating opportunities to experience the “8 C’s”: Control, Choice, Confidence, feeling Capable, Connection, Community, being Cared for by others, and Caring for others. In addition to the “8 C’s”, key components of WRBLO include participating in a weekly volunteer project, virtual group meetings, peer and mentor support from others with lived experience in the foster care system, and opportunities for skill building. This innovative program aims to increase well-being and empowerment outcomes for TAY and provide evidence that volunteering can be an effective tool for marginalized communities.

The ratio of occupational therapy practitioners (OTPs) to those who need occupational therapy (OT) services in the Philippines is one in every 30,000 (Delos Reyes, 2018). The country is composed of regions, some of which do not have OTPs while 55.12% are in the National Capital Region (NCR) (PAOT, 2017). Amid the COVID-19 pandemic, OT practice began to utilize telehealth as a service model (Delos Reyes et al., 2021). Telehealth allowed Filipino OTPs to reach clients, primarily children with developmental disorders, in their homes. However, Longo et al. (2020) posits that many parents do not feel prepared and motivated to participate actively in the rehabilitation of their children with disabilities. Typically, parents have not participated in therapy activities with their children, which is needed in telehealth (Eguia & Capio, 2022). Agaton and Cueto (2021) wrote training programs for parents should be provided on effective learning at home, dealing with child’s behavior, and technical support for online learning in order for them to have the same readiness. There is a need to explore the effectiveness of a program called Therahan in the Philippines to increase the family participation and satisfaction in the use of telehealth for OT services. Tirahan is a Filipino word for place of living. Before proceeding to telehealth sessions, all parents, guardians, grandparents, and carepartners of children with special needs will participate in a hybrid e-helper training program called Therahan which offers asynchronous sessions through printed or digital self-learning modules. These modules contain evidence-based information, steps, and practical tips on technical support, environmental modification, and behavioral management that are useful for telehealth, as well as synchronous sessions for coaching and guidance in applying gained knowledge and developing skills needed for effective telehealth services.