rejection


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rejection

 [re-jek´shun]
the immune response of the recipient to foreign tissue cells (antigens) after homograft transplantation, with the production of antibodies and ultimate destruction of the transplanted organ. In hyperacute rejection, there is an immediate response against the graft because of the presence of preformed antibody, resulting in fibrin deposition, platelet aggregation, and neutrophilic infiltration. In acute rejection, the response occurs after the sixth day and then proceeds rapidly. It is characterized by loss of function of the transplanted organ and by pain and swelling, with leukocytosis and thrombocytopenia. In chronic rejection, there is gradual progressive loss of function of the transplanted organ with less severe symptoms than in the acute form.

re·jec·tion

(rē-jek'shŭn),
1. The immunologic response to incompatibility in a transplanted organ.
2. A refusal to accept, recognize, or grant; a denial.
3. Elimination of small ultrasonic echoes from display.
[L. rejectio, a throwing back]

rejection

Immunology An immune reaction evoked by allografted organs; the prototypic rejection occurs in renal transplantation, which is subdivided into three clinicopathologic stages. See Cyclosporin A, Graft rejection, Graft-versus-host disease, Second set rejection, Tacrolimus, Transplant rejection.
Rejection types  
Hyperacute rejection Onset within minutes of anastomosis of blood supply, which is caused by circulating immune complexes; the kidneys are soft, cyanotic with stasis of blood in the glomerular capillaries, segmental thrombosis, necrosis, fibrin thrombi in glomerular tufts, interstitial hemorrhage, leukocytosis and sludging of PMNs and platelets, erythrocyte stasis, mesangial cell swelling, deposition of IgG, IgM, C3 in arterial walls
Acute rejection Onset 2-60 days after transplantation, with interstitial vascular endothelial cell swelling, interstitial accumulation of lymphocytes, plasma cells, immunoblasts, macrophages, neutrophils; tubular separation with edema/necrosis of tubular epithelium; swelling and vacuolization of the endothelial cells, vascular edema, bleeding and inflammation, renal tubular necrosis, sclerosed glomeruli, tubular 'thyroidization' Clinical ↓ Creatinine clearance, malaise, fever, HTN, oliguria
Chronic rejection Onset is late–often more than 60 days after transplantation, and frequently accompanied by acute changes superimposed, increased mesangial cells with myointimal proliferation and crescent formation; mesangioproliferative glomerulonephritis, and interstitial fibrosis; there is in general a poor response to corticosteroids

re·jec·tion

(rĕ-jek'shŭn)
1. The immunologic response to incompatibility of a transplanted organ.
2. A refusal to accept, recognize, or grant; a denial.
3. Elimination of small ultrasonic echoes from display.
[L. rejectio, a throwing back]

Rejection

Rejection occurs when the body recognizes a new transplanted organ as "foreign" and turns on the immune system of the body.
References in periodicals archive ?
The presence of histiocytic inflammation and/or mixed chronic and acute inflammation might also favor infection or aspiration over rejection. Predominant neutrophils in the epithelium and submucosa of small airways might favor infection over rejection.
Then there are rejections that come with ancestral thunder.
The regression analysis was used for exploring the predictive effect of body image and life satisfaction on outcome variable, rejection sensitivity among acne vulgaris students.
The cargo of products on the prohibition list of the destination is liable to rejection at the port of entry,'' Nwodo said.
From the in-depth analysis, it was clear that her high rejection sensitivity led her to adopt a negativity bias when she was engaged in interactions with people who she perceived as high in dominance who appeared to her to be acting in an unfriendly manner.
I can't tell you I've fully recovered from my scars of rejection, but I feel special, and I hold my head high.
How long a manuscript does stays with the journal before a letter of desk rejection is generated?
In a recent study published in the Journal of Clinical Medicine, Natera's assay detected acute rejection (AR) with 89% sensitivity and 0.87 area under the curve (AUC).
Because injured or dying cells from the donor release lots of donor DNA fragments into the bloodstream compared to normal donor cells, higher amounts of donor DNA indicate a higher risk for transplant rejection in the recipient.
However, reason for this generosity could not be found, since there is no significant difference in the degree of fairness or fear of rejection across the two genders.
TIM-3 is a type I membrane protein preferentially expressed on terminally differentiated Th1 cells, which seems to be central in the mechanisms of allograft rejection (15).
Mehtab Abbasi and Ayesha Gulalai also filed appeals against the rejection of their nomination papers by RO from NA-53 today while the PTI chief had already challenged the dismissal of nomination papers.