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J A Roake

Publications and source records attributed to J A Roake.

29 records · Page 2Linked to original sources
PubMed1994

Isolation and characterization of dendritic cells from mouse heart and kidney.

Dendritic cells (DC) are thought to be distributed throughout lymphoid and most nonlymphoid tissues. Single cell suspensions were prepared from mouse hearts and kidneys. Subsets of MHC class II-positive (Ia+) leukocytes from both sources expressed markers such as CDw32 Fc receptors, F4/80, and complement receptor type 3 (CD11b/CD18). The capacity of these cells to initiate primary in vitro immune responses was assessed using oxidative mitogenesis and allogeneic mixed leukocyte responses. After fractionation by density centrifugation, cell sorting, immunomagnetic bead separation, or cell panning, the stimulatory activity of kidney cell suspensions was found to reside in the low density, Ia+ leukocyte fractions after overnight culture (day 1). In contrast, freshly isolated (day 0) cells had considerably less or no activity in these assays. However, depletion of Ia+ or CD45+ cells on day 0 followed by overnight culture removed the stimulatory activity on day 1. Therefore, day 0 kidney cells contain Ia+ leukocytes that can acquire or up-regulate their stimulatory activity during overnight culture. Similar observations were made for cells isolated from hearts, except that a population of uncharacterized nonleukocytes with stimulatory activity was detected on day 0 but not day 1. The phagocytic capacity of the leukocytes was then examined. Subsets of Ia+ cells phagocytosed zymosan, as shown by two-color flow cytometry and other immunofluorescence studies, and the zymosan-positive cells from kidney were able to initiate primary responses. Overall, these data demonstrate the existence of DC in kidneys and hearts, and suggest that in situ these cells resemble immature rather than mature DC.

Animals↗
PubMed1994

The relationship between fever and acute rejection or infection following renal transplantation in the cyclosporin era.

In the past, fever has been considered to be an important sign of rejection in renal transplant patients but since the introduction and widespread use of cyclosporin this relationship has become less clear. We have studied the relationship between fever defined as a single temperature reading > or = 38.5 degrees C or recordings > or = 38.0 degrees C over 2 consecutive days, and acute rejection or infection in 99 consecutive renal transplants. Within the first 6 months after transplantation 90 acute rejection episodes were recorded in 61 patients and most (83%) were not associated with fever. Forty-seven episodes of fever were documented in 37 patients and ascribed to acute rejection (15), infection (17), antibody therapy (11) or other causes (4). Fever in the first 16 days was significantly more likely to be due to rejection than to infection (chi 2 = 24.47, p = < 0.001). Episodes of fever due to infection tended to occur after the 1st month, coincident with the peak incidence of cytomegalovirus (CMV) infection. However, with the exception of CMV disease, fever was not a reliable guide for the presence of infection, including septicemia.

Acute Disease↗
PubMed1993

Isolation of dendritic leukocytes from non-lymphoid organs.

These observation suggest that dendritic leukocytes from several different non-lymphoid organs in situ are functionally immature and that in this respect they more closely resemble epidermal LC than mature lymphoid DC. The exception appears to be the interstitial dendritic leukocytes from small and large intestinal lamina propria and Peyer's patches, where functional maturation could be attributed to constitutively secreted GM-CSF by lamina propria cell in situ, or alternatively to the isolation procedure which might lead to functional maturation of gut DC. After overnight culture, and possibly following organ transplantation, interstitial dendritic leukocytes may mature into potent activators of antigen-specific T-cell proliferation (immunostimulation). Further studies are needed to characterize dendritic leukocytes in solid non-lymphoid organs, and these may lead to new strategies for overcoming graft rejection by inhibiting the maturation of dendritic leukocytes after transplantation.

Animals↗
PubMed1988

Cadaver kidney retrieval for transplantation in Canterbury and Westland: 1972-1987.

In Canterbury and Westland, 106 cadaver kidney donors have provided 186 kidneys, which have been transplanted or submitted for transplantation. The overall rate of 16 donor/million population/year, since 1973, is high by international standards [1,2]. Male donors (68%) had a median age of 20 years, and females a median age of 24 years. Motor vehicle accidents were responsible for 58% of deaths, followed by subarachnoid haemorrhage (15%). Cadaver nephrectomy was performed outside normal working hours in 58% of cases. Overall, 10% of kidneys removed were discarded, but none have been discarded since September 1980. Anatomical anomalies were common (42%).

Adolescent↗
PubMed1983

Acute appendicitis: a quality assurance analysis.

The management of 722 patients admitted to Christchurch Hospital in 1979 with acute appendicitis (308) or non-specific abdominal pain (414) was such that 86% of the appendicitis patients had a timely removal of an inflamed but not perforated appendix and 9.2% of the patients with non-specific abdominal pain had an unnecessary appendicectomy. The mean stay in hospital was 4.8 days for patients who had a timely operation for acute appendicitis, 8.1 days for patients undergoing operation for perforated appendicitis, 6.1 days for patients who had non-specific abdominal pain and appendicectomy, and 2.7 days for patients who had non-specific abdominal pain without appendicectomy. There was no mortality.

Abdomen↗
PubMedDate not supplied

The role of dendritic cells and T cell activation in allograft rejection.

The lineage of dendritic leukocytes (DL) comprises cells that are widely distributed throughout lymphoid and non-lymphoid tissues, and which are phenotypically and functionally heterogeneous. These cells play a central role in the initiation of immune responses. Immature DL, which may be situated primarily in non-lymphoid tissues, are responsible for uptake and processing of native antigens, after which they migrate via blood and/or lymph into secondary lymphoid tissue, and develop into mature dendritic cells (DC). These cells can present foreign peptide-MHC complexes to resting T cells and deliver signals for T cell activation, thereby initiating the response. There is good evidence that DL can migrate from transplanted tissues into the recipient's lymphoid organs and initiate allograft rejection. Interruption of this process, by depleting DL before transplantation or by inhibiting their function, may contribute to the prevention of rejection in clinical transplantation.

Animals↗