Lymphodepletion is permissive to the development of spontaneous T-cell responses to the self-antigen PR1 early after allogeneic stem cell transplantation and in patients with acute myeloid leukemia undergoing WT1 peptide vaccination following chemotherapy

PR1, an HLA-A*0201 epitope shared by proteinase-3 (PR3) and elastase (ELA2) proteins, is expressed in normal neutrophils and overexpressed in myeloid leukemias. PR1-specific T cells have been linked to graft-versus-leukemia (GVL) effect. We hypothesized that lymphopenia induced by chemo-radiotherapy can enhance weak autoimmune responses to self-antigens such as PR1. We measured PR1-specific responses in 27 patients 30–120 days following allogeneic stem cell transplant (SCT) and correlated these with ELA2 and PR3 expression and minimal residual disease (MRD). Post-SCT 10/13 CML, 6/9 ALL, and 4/5 solid tumor patients had PR1 responses correlating with PR3 and ELA2 expression. At day 180 post-SCT, 8/8 CML patients with PR1 responses were BCR-ABL-negative compared with 2/5 BCR-ABL-positive patients (P = 0.025). In contrast, PR1 responses were detected in 2/4 MRD-negative compared with 4/5 MRD-positive ALL patients (P = 0.76). To assess whether the lymphopenic milieu also exaggerates weak T-cell responses in the autologous setting, we measured spontaneous induction of PR1 responses in 3 AML patients vaccinated with WT1-126 peptide following lymphodepletion. In addition to WT1-specific T cells, we detected PR1-specific T cells in 2 patients during hematopoietic recovery. Our findings suggest that lymphopenia induced by chemo-radiotherapy enhances weak autoimmune responses to self-antigens, which may result in GVL if the leukemia expresses the relevant self-antigen.Katayoun Rezvani, Agnes S. M. Yong, Stephan Mielke, Bipin N. Savani, Behnam Jafarpour, Rhoda Eniafe, Robert Quan Le, Laura Musse, Carole Boss, Richard Childs, A. John Barret

Moving from rhetoric to reality: adapting Housing First for homeless individuals with mental illness from ethno-racial groups

<p>Abstract</p> <p>Background</p> <p>The literature on interventions addressing the intersection of homelessness, mental illness and race is scant. The At Home/Chez Soi research demonstration project is a pragmatic field trial investigating a Housing First intervention for homeless individuals with mental illness in five cities across Canada. A unique focus at the Toronto site has been the development and implementation of a Housing First Ethno-Racial Intensive Case Management (HF ER-ICM) arm of the trial serving 100 homeless individuals with mental illness from ethno-racial groups. The HF ER-ICM program combines the Housing First approach with an anti-racism/anti-oppression framework of practice. This paper presents the findings of an early implementation and fidelity evaluation of the HF ER-ICM program, supplemented by participant narrative interviews to inform our understanding of the HF ER-ICM program theory.</p> <p>Methods</p> <p>Descriptive statistics are used to describe HF ER-ICM participant characteristics. Focus group interviews, key informant interviews and fidelity assessments were conducted between November 2010 and January 2011, as part of the program implementation evaluation. In-depth qualitative interviews with HF ER-ICM participants and control group members were conducted between March 2010 and June 2011. All qualitative data were analysed using grounded theory methodology.</p> <p>Results</p> <p>The target population had complex health and social service needs. The HF ER-ICM program enjoyed a high degree of fidelity to principles of both anti-racism/anti-oppression practice and Housing First and comprehensively addressed the housing, health and sociocultural needs of participants. Program providers reported congruence of these philosophies of practice, and program participants valued the program and its components.</p> <p>Conclusions</p> <p>Adapting Housing First with anti-racism/anti-oppression principles offers a promising approach to serving the diverse needs of homeless people from ethno-racial groups and strengthening the service systems developed to support them. The use of fidelity and implementation evaluations can be helpful in supporting successful adaptations of programs and services.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN42520374</p