Targeting of intragraft reactive oxygen species by APP-103, a novel polymer product, mitigates ischemia/reperfusion injury and promotes the survival of renal transplants

Inflammatory responses associated with ischemia/reperfusion injury (IRI) play a central role in alloimmunity and transplant outcomes. A key event driving these inflammatory responses is the burst of reactive oxygen species (ROS), with hydrogen peroxide (H₂ O₂ ) as the most abundant form that occurs as a result of surgical implantation of the donor organ. Here, we used a syngeneic rat renal transplant and IRI model to evaluate the therapeutic properties of APP-103, a polyoxalate-based copolymer molecule containing vanillyl alcohol (VA) that exhibits high sensitivity and specificity toward the production of H₂ O₂ . We show that APP-103 is safe, and that it effectively promotes kidney function following IRI and survival of renal transplants. APP-103 reduces tissue injury and IRI-associated inflammatory responses in models of both warm ischemia (kidney clamping) and prolonged cold ischemia (syngeneic renal transplant). Mechanistically, we demonstrate that APP-103 exerts protective effects by specifically targeting the production of ROS. Our data introduce APP-103 as a novel, nontoxic, and site-activating therapeutic approach that effectively ameliorates the consequences of IRI in solid organ transplantation.

CD1 Antigen Presentation and Autoreactivity in the Pregnant Human Uterus

PROBLEM

CD11c(HI) human decidual macrophages express several isoforms of CD1 molecules. Their expression pattern and function required investigation.

METHOD OF STUDY

CD11c(HI) macrophages were isolated from decidua. Expression of CD1 isoforms and their ability to present lipid antigens to T cells was studied.

RESULTS

CD1a, CD1c, and CD1d were all expressed on CD11c(HI) dMϕ, a pattern differing from those previously observed. Exposure of peripheral monocytes and dendritic cells to lipid isolates from decidua led to increased surface CD1a levels only. The CD1a and CD1c on dMϕ were able to present the appropriate lipid antigens to lipid antigen-specific T cells. Finally, autoreactivity of decidual T cells to CD1a was observed.

CONCLUSION

The unique pattern of expression of CD1 isoforms on CD11c(HI) dMϕ is consistent with organ-specific roles of CD1 in human T-cell responses. dMϕ are able to present lipid antigens to both peripheral and decidual T cells and are major antigen-presenting cells in human decidua.

CD11cHI macrophages are specialized APCs in the early human placenta (169.45)

The human maternal-fetal interface is a unique environment by which there is a necessary establishment of maternal tolerance to fetal antigens as well as uterine spiral artery remodeling and placental growth. Decidual macrophages (dMΦs) comprise approximately 20% of all leukocytes at this interface. Previously we identified two distinct populations based upon CD11c and have been termed, CD11cHI and CD11cLO MΦs (J Immunol. 2011; 186(4)). Based upon microarray analysis, CD11cHI and CD11cLO dMΦs were shown to have significantly divergent functions. Using a DQ-BSA assay we demonstrate that CD11cHI cells process exogenous protein antigens efficiently while processing by CD11cLO cells is very low. Furthermore, several CD1 molecules are expressed on the surface of CD11cHI dMΦs including CD1a, CD1c and CD1d. CD1 molecules are non-polymorphic glycolipid-presenting molecules that have no known function at the maternal-fetal interface. In order to determine functional relevance, we utilized established CD1-specific T cell clones and known ligands for CD1a and CD1c [CD8.2, dideoxymycobactin (DDM); CD8.1, mannosyl-β1-phosphomycoketide (MPM)] respectively. CD11cHI dMΦs, but not CD11cLO dMΦs, were found to specifically stimulate these T cell clones. Thus, these data suggest that the CD11cHI dMΦs may function in two different antigen-presenting systems at the maternal-fetal interface during early human pregnancy, peptide presentation and glycolipid presentation.

A holistic approach to vaso-occlusive pain crisis in children with sickle cell disease

A significant number of children with sickle cell disease suffer from episodes of acute recurrent vaso-occlusive pain crisis. Unfortunately, very limited published information is available about specific pain management practices used for these patients. There is even less information available on the use of an interdisciplinary approach for management of sickle cell crisis pain. The purpose of this article is to review the genetic cellular pathophysiology, the sickling process, vaso-occlusive crisis, and management of pain associated with sickle cell disease in children. The article further examines an interdisciplinary approach for the management of vaso-occlusive pain crisis.

Age and health perceptions among elderly blacks

1. By the year 2000, minority group members will comprise 20% of the total elderly population. Three million blacks will be 65 years or older by that time. 2. Many health-care providers have limited knowledge, experience, or understanding of the minority perspective as it relates to those decisions that influence the health and illness behaviors of this underserved group. 3. A person's self-perception of his physical and mental abilities, as well as his own health status, will influence his willingness to seek and accept help. 4. Interacting with the black elderly about age and health perceptions can allow nurses to demonstrate personal interest, obtain pertinent health-related data, and gain insights into the coping strategies that these individuals have successfully used for long periods.