Cytotoxic T cell response to minor histocompatibility antigens: apparent lack of H-2 restriction in killers stimulated by membrane fragments.

The secondary cytotoxic T cell response of BALB/c to B10.D2 or DBA/2 minor histocompatibility antigens in vitro requires the participation of an adherent cell. Nylon wool-passed spleen cells were only able to respond to nonadherent intact stimulator cells, or to membrane fragments derived from those cells, if a syngeneic adherent cell were present in the cultures. When the H-2 restriction properties of cytotoxic cells generated in response to various types of stimulation were analyzed, it was found that responses to B10.D2 or DBA/2 intact cells were always H-2 restricted. Responses to syngeneic adherent cells presenting B10.D2 or DBA.2 freeze-thaw antigen were either entirely or predominantly lacking in H-2 restriction as defined by efficient competition by B10 (H-2b) cold target cells. These unrestricted killers appeared to recognize minor histocompatibility as an independent determinant rather than as an H-2d/minors moiety cross-reaction with H-2b, because they were not absorbed by BALB.B (H-2b) macrophage monolayers, but were absorbed by B10 monolayers. Similarly, B10 but not BALB.B cold targets were able to compete for the anti-B10.D2 killers. These experiments eliminate the possibility that the lack of restriction was due to an H-2b restricted receptor cross-reactive with H-2b. Possible models to explain these findings are discussed.

Knowledgeable, consistent, competent care: meeting the challenges of delivering quality cancer care in remote northern communities.

The Northwestern Ontario Regional Cancer Centre (NWORCC) has created outreach services that provide chemotherapy and supportive care to clients in thirteen small, remote communities. Located 100-600 km from the NWORCC, these satellite oncology services are staffed by local physicians, specially prepared nurses and support staff. The present paper reports selected findings from an evaluation of the service, based on two rounds of site visits, interviews and surveys of providers and clients. Although the consensus was that quality care was being delivered, local hospitals and other organizations had to address a variety of challenges. Those discussed in the paper include: maintaining provider competency, strengthening supportive care networks, and adjusting staffing and other resources to meet increased demands for care.

Antibody against Haemophilus influenzae protein D in patients with chronic conditions causing secondary immunodeficiency.

Prevalence of non-typeable Haemophilus influenzae (NTHi) in the etiology of invasive infections in immunocompromised individuals is increasing. Serum IgG antibody levels to H. influenzae protein D (PD) were significantly lower in adults suffering from chronic conditions causing secondary immunodeficiency (COPD, cancer, chronic renal failure, and diabetes) compared to age-matched healthy controls. A lack of naturally acquired antibody against this highly conserved antigen may contribute to an increased susceptibility to invasive NTHi disease. As COPD patients frequently infected with NTHi during disease exacerbations were unable to develop antibody response to PD, such defect could potentially contribute to the pathogenesis. Considering that pediatric PD-containing vaccines show protective effect against NTHi-caused otitis media, our data suggest the possibility of improving the defense against NTHi in COPD patients using immunization against PD. Although more research on the role of anti-PD antibody in protection against invasive NTHi disease is warranted, development of adult formulations of PD-based vaccines may be advantageous for prevention of severe infections in immunocompromised individuals.

A skills programme for preclinical medical students.

An education programme in which preclinical medical students are introduced to common procedural skills is described. This programme is presented by a multidisciplinary health care team using short lectures, demonstrations, mannequin practice, and, in selected instances, practice on class-mate volunteers. The programme was evaluated by the students immediately following the presentation and for one class during their clinical activities one year later. The students' support for this programme was generally enthusiastic and remained undiminished upon reflection 12 months later.