Complications of Cardiac and Lung Transplantation
Stephen M. Cohn, Matthew O. Dolich in Complications in Surgery and Trauma, 2014
Hyperacute rejection occurs due to the presence of pre-formed antibodies to the donor graft. The incidence of hyperacute rejection has decreased with careful ABO matching, and determination of a recipient’s panel reactive antibody allows for risk stratification for rejection episodes. The widespread use of virtual cross-match, which employs flow cytometry to determine incompatible antigens in potential donors, has also reduced the likelihood of hyperacute rejection episodes. Consequences of hyperacute rejection include microvascular thrombosis with biventricular failure. Treatment is supportive with mechanical circulatory support and cytolytic immunosuppression with plasmapheresis [15,17]. Despite all aggressive measures, mortality remains high for this devastating complication.
Serological Typing of HLA-A, -B, and -C Antigens
M. Kam, Jeffrey L. Bidwell in Handbook of HLA TYPING TECHNIQUES, 2020
The aim of screening patients’ sera is to determine whether any HLA antibody is present and its specificity(ies) if present. The methods used to test for such antibodies and the panel of lymphocytes used locally are described in the section,"HLA-A, -B, and -C Typing Reagents". A selected cryopreserved lymphocyte panel, which ensures testing of all the HLA specificities, or a random panel using the lymphocyte preparations typed in the laboratory, can be used. Whatever panel is used it is essential that the serum analysis be comprehensive. The screening result is usually expressed as the percentage of panel reactive antibody (% PRA), i.e., the percentage of the screening panel positive with the test serum.
The humoral response to lung transplantation
Wickii T. Vigneswaran, Edward R. Garrity, John A. Odell in LUNG Transplantation, 2016
Both the CDC and flow cytometric assays rely on cellular targets. The CDC assay determines whether recipient serum can lyse non-self T or B lymphocytes. The lymphocytes are collected from a local representative population, as in the case of the panel-reactive antibody (PRA) assay or from the potential lung donor in the crossmatch test. The presence of autoantibodies may provide a false-positive crossmatch result, which is a scenario that can be avoided by the addition of dithiothreitol. The CDC does not differentiate between HLA class I and class II antibodies, nor between HLA and non-HLA antibodies.
Memory B cells and long-lived plasma cells in AMR
Published in Renal Failure, 2022
Wenlong Yue, Jia Liu, Xiaohu Li, Luman Wang, Jinfeng Li
Moreover, relevant studies have shown that memory B cells are produced much earlier than long-lived plasma cells; as a consequence, the memory B-cell-mediated DSA response cannot be effectively resolved [53]. As a result, panel reactive antibody (PRA)-negative patients are often presumed to be unsensitized patients. The patient’s degree of sensitization is based on detection of PRAs. Nevertheless, PRA-negative patients with a large number of memory B cells quickly produce DSAs when exogenous antigen reintroduction occurs. These patients may be clinically classified as unsensitized patients. Therefore, AMR can still occur after transplantation in some PRA-negative patients, perhaps because of the impact of memory B cells [54,55]. Quantifying memory B cells in peripheral blood and GCs and determining their functions may be important approaches to monitor AMR [56].
Association between cumulative rATG induction doses and kidney graft outcomes and adverse effects in kidney transplant patients: a systematic review and meta-analysis
Published in Expert Opinion on Biological Therapy, 2021
Keyhan Mohammadi, Behrouz Khajeh, Simin Dashti-Khavidaki, Sakineh Shab-bidar
The characteristics of the included studies are summarized in Table 1. Of 26 retrieved studies, three RCTs consisting of 154 patients [16,28,29] and 23 cohort studies consisting of 3457 patients [11,13,17,18,20,26,27,30–45] were included. Two studies [30,45], consisting of 190 patients did not report gender distribution in their population. Other studies consisted of 1306 women and 2115 men. The mean age of subjects was 50.36 ± 5.98 years with a range of 37 to 73.5 years. The mean age of the patients was not reported in one study [45]. The mean duration of patients’ follow-up was 23.36 ± 21.21 months (range 3 to 117 months). The mean administered cumulative doses of rATG considering all arms of all studies was 5.88 ± 2.8 mg/kg with a range of 1.5 to 18.75 mg/kg. Most of the included studies enrolled both the low and high immunological risk kidney transplant recipients. The high immunological risk definition varies across studies; however, patients with a history of prior renal allograft transplantation, elevated peak percent panel reactive antibody (PRA) and/or presence of donor-specific antibody were considered as high risk in most of the studies.
A review of imlifidase in solid organ transplantation
Published in Expert Opinion on Biological Therapy, 2021
Avoiding DSA in many cases translated simply to avoiding sensitized recipients. But in reality, a significant number of patients in need of an organ transplant are sensitized to HLA, by way of either transfusions, prior transplants, or pregnancy. Of these patients, those who are highly sensitized, with calculated panel reactive antibody (CPRA) over 98%, are extremely unlikely to ever find a compatible donor. It has long been known that kidney transplantation is the preferred treatment for end-stage renal disease (ESRD), and that it affords patients a substantial survival benefit when compared to dialysis [3]. A multi-center retrospective evaluation of outcomes specific to sensitized patients revealed that, despite the challenges inherent in getting these patients to transplant, the survival benefit of transplantation holds true even when the kidney they receive is HLA incompatible [4]. In fact, their long-term survival is nearly doubled by transplantation compared to similar patients who remain on the waiting list without a transplant.
Related Knowledge Centers
- Antibody
- Immunology
- White Blood Cell
- Lymphocyte
- Blood
- Antigen
- Leukocyte Antigen
- Medical Laboratory
- Organ Transplantation
- Serum