antithymocyte globulin

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Related to antithymocyte globulin: cyclosporine, Atgam, antithymocyte globulin equine


any of numerous proteins that are insoluble in water or highly concentrated salt solutions but soluble in moderately concentrated salt solutions. All plasma proteins except albumin and prealbumin are globulins. The plasma globulins are separated into five fractions by serum protein electrophoresis (SPE). In order of decreasing electrophoretic mobility these fractions are the alpha1-, alpha2-, beta1-, and beta2-globulins, and the gamma globulins.

The globulins include carrier proteins, which transport specific substances; acute phase reactants, which are involved in the inflammatory process; coagulation factors; complement components; and immunoglobulins. Examples are transferrin, a beta1-globulin that transports iron, and alpha1-antitrypsin, an acute phase reactant that inhibits serum proteases. The gamma globulin fraction is almost entirely composed of immunoglobulins.
accelerator globulin factor V, one of the coagulation factors.
antihemophilic globulin (AHG) factor VIII, one of the coagulation factors.
antilymphocyte globulin (ALG) the gamma globulin fraction of antilymphocyte serum; used as an immunosuppressant in organ transplantation. The term is sometimes used interchangeably with antithymocyte globulin.
antithymocyte globulin (ATG) the gamma globulin fraction of antiserum derived from animals (such as rabbits) that have been immunized against human thymocytes; an immunosuppressive agent that causes specific destruction of T lymphocytes, used in treatment of allograft rejection. The term is sometimes used interchangeably with antilymphocyte globulin.
bacterial polysaccharide immune globulin (BPIG) a human immune globulin derived from the blood plasma of adult human donors immunized with Haemophilus influenzae type b, pneumococcal, and meningococcal polysaccharide vaccines; used for passive immunization of infants under 18 months of age.
cytomegalovirus immune globulin a purified immunoglobulin derived from pooled adult human plasma selected for high titers of antibody against cytomegalovirus; administered intravenously for treatment and prophylaxis of cytomegalovirus disease in transplant recipients.
gamma globulin
hepatitis B immune globulin (HBIG) a specific immune globulin derived from plasma of human donors with high titers of antibodies against hepatitis B surface antigen (HBsAg); used for postexposure prophylaxis following contact with HBsAg-positive materials, also administered to infants of HBsAg-positive mothers.
hyperimmune globulin any of various immune globulin preparations especially high in antibodies against certain specific diseases.
immune globulin
2. a concentrated preparation containing mostly gamma globulins, predominantly IgG, from a large pool of human donors; used for passive immunization against measles, hepatitis A, and varicella and for treatment of hypogammaglobulinemia or agammaglobulinemia in immunodeficient patients, administered intramuscularly. See also immune g. intravenous (human).
immune globulin intravenous (human) a preparation of immune globulin suitable for intravenous administration; used in the treatment of primary immunodeficiency disorders and idiopathic thrombocytopenic purpura, and as an adjunct in the treatment of Kawasaki disease and the prevention of infections associated with chronic lymphocytic leukemia, bone marrow transplantation, and pediatric human immunodeficiency virus infection.
immune human serum globulin immune globulin (def. 2).
immune serum globulin immune g. (def. 2).
pertussis immune globulin a specific immune globulin derived from the blood plasma of human donors immunized with pertussis vaccine; used for the prophylaxis and treatment of pertussis.
rabies immune globulin a specific immune globulin derived from plasma of human donors hyperimmunized with rabies vaccine; administered in conjunction with rabies vaccine in cases of bite or scratch exposure to known or suspected rabid animals.
respiratory syncytial virus immune globulin intravenous a preparation of immunoglobulin G from pooled adult human plasma selected for high titers of antibodies against respiratory syncytial virus; used for passive immunization of infants and young children.
Rh0(D) immune globulin a specific immune globulin derived from human blood plasma containing antibody to the erythrocyte factor Rh0(D); used to prevent Rh-sensitization of Rh-negative females and thus prevent erythroblastosis fetalis in subsequent pregnancies; administered within 72 hours after exposure to Rh-positive blood resulting from delivery of an Rh-positive child, abortion or miscarriage of an Rh-positive fetus, or transfusion of Rh-positive blood. It is also used as a platelet count stimulator in the treatment of idiopathic thrombocytopenic purpura.
serum g's all plasma proteins except albumin, which is not a globulin, and fibrinogen, which is not in the serum. The serum globulins are subdivided into alpha-, beta-, and gamma-globulins on the basis of their relative electrophoretic mobilities.
specific immune globulin a preparation of immune globulin derived from a donor pool preselected for high antibody titer against a specific antigen, such as hepatitis B immune globulin.
tetanus immune globulin a specific immune globulin derived from the blood plasma of human donors who have been immunized with tetanus toxoid; used in the prophylaxis and treatment of tetanus.
thyronine-binding globulin (TBG) (thyroxine-binding globulin) an acidic glycoprotein that is the main binding protein in the blood for thyroxine, and less firmly for triiodothyronine.
vaccinia immune globulin a specific immune globulin derived from the blood plasma of human donors who have been immunized with vaccinia virus smallpox vaccine; used as a passive immunizing agent.
varicella-zoster immune globulin (VZIG) a specific immune globulin derived from plasma of human donors with high titers of varicella-zoster antibodies; used for prevention or amelioration of varicella in immunocompromised patients exposed to the disease and in neonates whose mothers develop varicella in the perinatal period.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

antithymocyte globulin

An agent used for immunosuppression in organ transplantation.
See also: globulin
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
Lawendowski et al., "Polyclonal rabbit antithymocyte globulin exhibits consistent immunosuppressive capabilities beyond cell depletion," Transplantation, vol.
Caption: Figure 6: CD3+ and CD19+ lymphocyte subset studies shows depletion of T cells and B cells immediately after induction with rabbit antithymocyte globulin and rituximab.
Abbreviations ANC: Absolute neutrophil count ATG: Antithymocyte globulin (ATG) AZA: Azathioprine CTACE: Common terminology criteria for adverse events EC-MPS: Enteric-coated mycophenolate sodium G-CSF: Granulocyte colony stimulating factor GM-CSF: Granulocyte-monocyte colony-stimulating factor HHV-6: Herpesvirus-6 IL2-R antagonist: Interleukin receptor antagonist KTR: Kidney transplant recipients LON: Late-onset neutropenia MTOR inhibitors: Mammalian target of rapamycin inhibitors MMF: Mycophenolate mofetil PVB19: Parvovirus B19 CMV: Cytomegalovirus EBV: Epstein-Barr virus TMP-SMZ: Trimethoprim-sulphamethaxazole.
She received alemtuzumab with her first allogeneic transplant and conditioning with antithymocyte globulin before her second transplant, resulting in significant in vivo T-cell depletion; she was also receiving adrenal corticosteroids.
Successful treatment of acquired amegakaryocytic thrombocytopenic purpura refractory to corticosteroids and intravenous immunoglobulin with antithymocyte globulin and cyclosporin.
Immunosuppressive agents included azathioprine, cyclosporine, antithymocyte globulin, antilymphocyte globulin and later tacrolimus, antiCD25 (T-cell receptor) monoclonal antibodies basiliximab and dacluzumab, and mTOR (mammalian target of rapamycin) inhibitors, sirolimus and everolimus.
Patients were then immunoablated with a combination regimen of high-dose cyclophosphamide, a total of 200 mg/kg, along with equine antithymocyte globulin to eliminate T cells.
Starzl Transplantation Institute treated 82 patients with rabbit antithymocyte globulin for T-cell depletion just before transplantation and with only 1 immunosuppressant after transplantation, rather than the usual 2- or 3-drug cocktail.
The next 57 patients received these two drugs with their cell transplants plus the immune suppressant, a protein called antithymocyte globulin. These patients fared better, says study coauthor Francoise Bernaudin of Saint Louis Hospital in Paris.
Immunosuppression consisted of Imuran [R], prednisone, cyclosporine, and antithymocyte globulin. Insulin therapy was utilized postoperatively and gradually reduced over 2 months.
Studies have shown that basiliximab reduces acute rejection rates better than placebo and has a comparable effect on acute rejection rates as antithymocyte globulin (ATG) or alemtuzumab in low risk patients; but, ATG and alemtuzumab are more efficacious in reducing acute rejection rates in high risk patients [9-16].
Induction was done with antithymocyte globulin in the dose of 3 mg/kg and triple immunosuppression was given with tacrolimus, mycophenolate mofetil, and prednisolone.