B-32. Immunophacology III. (antibodies and fusion proteins). Flashcards
Polyclonal antibody therapies
- ) Intravenous Immunoglobulin (IVIG)
- ) Anti-Rho (D)
- ) Polyclonal Antibodies
- ) Hyperimmune globulins
Intravenous Immunoglobulin (IVIG) MOA
- )Neutralizes superantigens and autoantibodies
- ) Blocks macrophages FcRs
- ) Inhibits complement/immune complex-mediated tissue destruction (isolated from blood of healthy donors)
Indication of Intravenous Immunoglobulin
- ) Immune Thrombocytopenic Purpura
- Platelet surface antigen autoantibodies (anti-GP-IIb/IIIa, etc.) - ) Kawasaki disease and other vasculitis
- ) Guillain-Barre syndrome
- Muscle weakness beginning distally (C. jejuni and CMV-related) - ) Polymyositis
- unknown auto-antigen - )SLE
- ) Immunoglobulin deficit
- as in X-linked agammaglobulinemia etc.
Intravenous Immunoglobulin side effects
allergy
Indication for Anti-Rho
Given to Rh- mothers after delivery of Rh+ baby to suppress mother’s antibody production
Polyclonal Antibodies includes
Anti-lymphocyte and thymocyte globulins
Polyclonal antibodies MOA
Polyclonal antibodies from rabbit/horse immunized by human lypho-/thyomocytes that kill/block human lymphocytes
Indication for polyclonal antibodies
Transplants prevent acute rejection and used wen rejection of organ is likely.
Also a pretreatment of BM rafts with anti-lymphocyte globulins reduces incidence of GVHD
Side effects of polyclonal antibodies
- ) Dyspnea
- ) Serum sickness
- ) Fever and GI issues
What are hyperimmune globulins like? How are they different? What are they used for?
Hyperimmune globulins are similar to IVIG but isolated from donors with high titers of Ab specific to certain antigens.
Used for passive immunization of viral infections (CMV, VZV, HBV, rabies) and toxicological issues (dioxin, snake venom, etc.)
-momab means?
100% mouse
-ximab means?
chimeric; 75% human
-zumab means?
95% human
-umab means?
100% human
Anti-T cell mAbs names
- ) Muromonab-CD3
2. ) Basiliximab (Daclizumab, a humanized version)
Muromonab-CD3
MOA?
Indication?
Side effect?
Muromonab-CD3 is the first mAb drug; against CD3 (a TCR coreceptor) causing rapid reduction of T cell count.
Indication is kidney transplant, against acute rejection
Side effect is cytokine release syndrome, flu-like, sometime shock
Basiliximab MOA? Indication? Side effecs? What is Daclizumab?
MOA: Antibody against IL-2 receptor (specific CD-25, the alpha chain of IL-2R) inhibiting T-cell activation
Indication: transplants against acute rejection (less effective than anti-lymphocyte and thymocyte globulins)
Side effects: GI symptoms
Daclizumab, a humanized version, was withdrawn due to enecephalitis risk
Rituximab and Ocrelizumab MOA
Binds CD20 B cell antigen (malignant and normal B cells, but not plasma cells). A single treatment reduces B cell count for more than a month via complement and cell mediated B cell destruction.
Indications of Rituximab and Ocrelizumab
1.) B-cell lymphomas- of lower malignancy
2.) CLL
3.) Rheumatoid arthritis (2 doses in 2 weeks; again after 6 months break)
4.)Vasculitis
Off-label: treatment resistant AI diseases
5.) MS- ocrelizumab for progressive or relapsing-remitting types
Rituximab and Ocrelizumab side effects
- ) Infusion reactions- avoidable with steroid, paracetamol+ anti-HA prophylaxis
- ) Infections (and increased risk of lymphoma if given with TNF-alpha antagonist)
Other anti-CD20 mAbs
- ) Obinutuzumab (CLL, follicular lymphoma)
- ) Ofatumumab (CLL, FL, diffuse large B-cell lymphoma, RA, MS)
- ) Y90-Ibritumomab-tiuxetan
- ) Veltuzumab (NHL, non-Hodgkin lymphoma)
Alemtuzumab MOA
- Anti-CD52 mAb.
- CD52 is a glycoprotein on B-, T-, NK cells and macrophages
- Possible function as anti-adhesion molecule increased cellular movement.
Alemtuzumab indication
Used for MS, no longer used for B-cell CLL (withdrawn)
Side effect of Alemtuzumab
myelosuppresion
Anti-TNF alpha drugs
- ) Etanercept
- ) Infliximab
- ) Adalimumab
- ) Golimumab
- ) Certolizumab pegol
Etanercept is a? Binds? Given how and how often?
- A fusion protein of 2 TNF alpha receptor and IgG Fc portions
- binds free TNF alpha
- given s.c. 1-2x/week
Infliximab is a? Given how and how often?
- Chimeric mAB
- given i.v. 1-2x/month
Adalimumab is a? Given how and how often?
- human mAb
- given s.c. 1-2x/week
Golimumab is a? Given how and how often?
- human mAb
- given s.c. 1x/month