Publications

INTRODUCTION

Deceased donors are considered high infectious risk donors (IRDs) based on criteria thought to be associated with risk of HIV transmission. Significant variation exists in provider willingness to utilize IRD kidneys. Little is known about how patients view these organs. Our aim was to explore patient attitudes toward IRDs and IRD kidney transplantation.

METHODS

Patients were recruited from a single-center deceased donor waitlist. Focus groups stratified by age and race were conducted to ascertain patient attitudes toward IRD kidney transplantation. Transcripts were examined using standard qualitative methods.

RESULTS

Patients considered IRD kidneys most appropriate for patients at high risk of death or with poor quality of life on dialysis. Patients felt unprepared to receive organ offers, especially from IRDs. They desired information about IRD behaviors, kidney quality, and probability of undetected infection. Patients weighed the opinion of their nephrologist most heavily when deciding about organ offers. A brief education session about donor screening resulted in increased willingness to consider IRD kidneys.

CONCLUSIONS

Lack of preparedness contributes to patient apprehension toward IRD organs. Ongoing transplant education seems necessary. The non-transplant nephrologist seems to be the most trusted source of information.

Initiation of the adaptive immune response to Mycobacterium tuberculosis occurs in the lung-draining mediastinal lymph node and requires transport of M. tuberculosis by migratory dendritic cells (DCs) to the local lymph node. The previously published observations that 1) neutrophils are a transiently prominent population of M. tuberculosis-infected cells in the lungs early in infection and 2) that the peak of infected neutrophils immediately precedes the peak of infected DCs in the lungs prompted us to characterize the role of neutrophils in the initiation of adaptive immune responses to M. tuberculosis. We found that, although depletion of neutrophils in vivo increased the frequency of M. tuberculosis-infected DCs in the lungs, it decreased trafficking of DCs to the mediastinal lymph node. This resulted in delayed activation (CD69 expression) and proliferation of naive M. tuberculosis Ag85B-specific CD4 T cells in the mediastinal lymph node. To further characterize the role of neutrophils in DC migration, we used a Transwell chemotaxis system and found that DCs that were directly infected by M. tuberculosis migrated poorly in response to CCL19, an agonist for the chemokine receptor CCR7. In contrast, DCs that had acquired M. tuberculosis through uptake of infected neutrophils exhibited unimpaired migration. These results revealed a mechanism wherein neutrophils promote adaptive immune responses to M. tuberculosis by delivering M. tuberculosis to DCs in a form that makes DCs more effective initiators of naive CD4 T cell activation. These observations provide insight into a mechanism for neutrophils to facilitate initiation of adaptive immune responses in tuberculosis.

Contributions by basophils to allergic and helminth immunity remain incompletely defined. Using sensitive interleukin 4 (Il4) reporter alleles, we demonstrate here that basophil IL-4 production occurs by a CD4(+) T cell-dependent process restricted to the peripheral tissues affected. We genetically marked and achieved specific deletion of basophils and found that basophils did not mediate T helper type 2 (T(H)2) priming in vivo. Two-photon imaging confirmed that basophils did not interact with antigen-specific T cells in lymph nodes but engaged in prolonged serial interactions with T cells in lung tissues. Although targeted deletion of IL-4 and IL-13 in either CD4(+) T cells or basophils had a minimal effect on worm clearance, deletion from both lineages demonstrated a nonredundant role for basophil cytokines in primary helminth immunity.