Immunosuppresive antibodies by Dr Nikhil Bansal

1. Immunosuppresive Antibodies
Dr Nikhil Bansal
J.N.M.C.,Wardha

2. Types
 Antilymphocyte & Antithymocyte
antibodies
 Muromonab - CD3
 Immune Globulin Intravenous (IGIV)
 Anti-D Immunoglobulin
 Hyperimmune Immunoglobulins

3. Antilymphocyte (ALG) &
Antithymocyte (ATG) Antibodies
 Polyclonal antibodies
 Obtained by immunization of large animals
(horses or sheep) with human lymphoid cells.
 ATG binds to T-lymphocytes & depletes them.
 ALG acts primarily on small long lived peripheral
lymphocytes.

4. Destruction or inactivation of T-cells
Impairment of delayed HSR & cellular
immunity
*While humoral Ab formation remains relatively intact.

5. Uses
 As a potent immunosuppressant
 To suppress acute allograft rejection
episodes.
 Management of solid organ or bone
marrow transplantation.
 In induction regimens.

6. Adverse effects
 Local pain & erythema at the site of
inj(type3 HS)
 Anaphylactic reaction
 Serum sickness reactions to ALG

7. Muromonab-
CD3
 A murine monoclonal antibody against
CD3 glycoprotein

8. Binding of Muromonab-CD3 to CD-3 Ag
Obstruction of binding of MHC 2 Ag complex to the T-cell
receptor
Ag recognition is interfered
Precipitation of T-cell in immune response is prevented
T-cell rapidly disappear from circulation
IMMUNE BLOCK STAGE

9. Uses
 As induction therapy together with
corticosteroids & azathioprine with delayed
use of cyclosporine in ‘sequential regimen’ for
organ transplant
 Also valuable for steroid resistance rejection
reactions & has been use to deplete T-cells
from donor bone marrow before transplant

10. Adverse effect
 It initially may produce ‘cytokine release’
syndrome with flu like symptoms: chills, rigor,
wheezing, occasionally aseptic meningitis.
* High dose of corticosteroid pretreatment reduce the
reaction.

11. Immune Globulin Intravenous
(IGIV)
 A quit different approach to
immunomodulation is the i.v. use of
polyclonal human immunoglobulin.
 This Ig (usually IgG) is prepared from
pools of thousands of healthy donors &
no specific Ab is targeted.
 Its precise mech. of action is still
controversial.

12. Possible Mechanism Of Action
of IGIV
It includes reduction of
 Helper T-cells
 Increase of suppressor T-cells
 Decrease of spontaneous Ig production
 Fc receptor blockade
 Increase Ab catabolism &
 Idiotypic-anti-idiotypic interactions with
“pathologic antibodies”

13. Uses
It is effective in:
 Ig deficiency
 Autoimmune disorder
 HIV
 Bone marrow transplants
 SLE &
 Idiopathic, thrombocytopenic purpura.

14. Anti-D Immunoglobulin
 Human IgG having high titre of Ab
against Rh (D) antigen.
 Binds to Rh Ag & does not allow them
to induce antibody formation in Rh –ve
individuals.
 Used for prevention of post partum
formation Ab in Rh-D negative.

15. Hyper immune
Immunoglobulin
 IGIV preparations made from pools of
selected human or animal donors with
high titre of antibody against particular
agents of interest (viruses and toxins)
 Intravenous administration of hyper
immune globulins is passive transfer of
high titre antibody that either reduces
risk or severity of infection.

16. Uses
Various hyper immune IGIV are
available for treatment of Respiratory
Syncytial Virus, Cytomegalo Virus,
Vericella Zoster, Hepatitis B, tetanus,
rabies and digoxin overdose.

17. THANK YOU