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 ?
Do you beat up or insult a potential employer who sends you a rejection letter?
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).
If there was no sign of rejection on the biopsy, the prednisone dose was tapered and withdrawn over 2 weeks.
I haven't done an excellent job dealing with rejections I've come across in the past.
Social norms dictate that we should forgive someone if they apologise, which puts the targets of social rejection in a difficult position if they aren't ready to do this or think the apology is insincere.
Law Firms with the Highest Allowance Rates after Mayo/Myriad Rejections:
The risk of heart transplant rejection can be reduced by desensitising patient antibodies, according to research presented today at Heart Failure 2017 and the 4th World Congress on Acute Heart Failure.1 The breakthrough comes on the 50th anniversary of heart transplantation.
The 1 h and 12-day protocol allograft biopsies showed no evidence of rejection. The clinical course of the patient is shown in Figure 1.
The first step in finding a successful response to an Alice rejection is to investigate how the USPTO has interpreted Alice.
However, by focusing on the technological problem solved by the invention, drafting claims so as to not recite a judicial exception, and perhaps piggy-backing off of allowable claim limitations, applicants should be able to overcome Section 101 rejections.
During the 2004 International Society of Heart and Lung Transplantation (ISHLT), cellular rejection grades were revised and AMR was formally defined [3].
To measure early childhood rejections, we used several measures previously used in the literature.