Interferons and interleukins are cytokines that play an important role in the immune system. Interferons are proteins produced by cells in response to viral infections that activate immune responses in other cells. The three main types are alpha, beta, and gamma interferons. Interleukins are cytokines that are primarily produced by lymphocytes and macrophages to mediate communication between immune cells. There are over 30 identified interleukins that activate immune responses. Both interferons and interleukins have therapeutic applications for treating viral infections and cancers by enhancing immune activation. They are administered through intravenous or subcutaneous injection.

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2.  An antiviral substance & is the first line of defence against
viral attacks.
 Term ‘interferon’ orginated from the ‘interference’ of this
molecule on virus replication.
 Interferons are a family of host coded proteins produced by
cells on induction by viral or non-viral inducers.
 Interferons by itself has no direct action on viruses but it acts
on other cells of the same species, rendering them refractory to
viral infection.
INTERFERONS
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3.  Interferons are inactivated by proteolytic enzymes but not by
nucleases or lipases.
 They resist heating at 56-60oC for 30-60mins & stable over a
range of pH 2-10, except gamma IFN which is liable at pH 2.
 Mol.wt of 17000 Da - non dialysable & non-sedimentable.
 Poorly antigenic, so no routine tests are available for their
detection & estimation.
 Interferon assay-based on its biological activity, such as ability
to inhibit plaque formation by sensitive virus.
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4.  Potency of IFN is expressed as International Units(IU) per mL.
 Interferons are non-toxic, non-antigenic, diffuses freely in the
body & has a wide spectrum of antiviral activity.
 So it is an ideal candidate for use in prophylaxis & treatment of
viral infection.
 Interferons are stored at 2 – 8°c
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5.  Proteins in nature & many of them are glycoproteins.
 Broadly classified into 3 groups- structure & function.
INTERFERONS
Interferon-α
(INF-α)
Interferon-β
(INF-β)
Interferon-γ
(INF-γ)
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6.  Alpha interferon
• Also known as Leukocyte interferon.
• Produced by leukocytes following induction by suitable
viruses.
• Non-glycosylated protein.
• Atleast 16 antigenic subtypes have been identified.
 Beta interferon
• Fibroblast interferon.
• Produced by fibroblasts & epithelial cells following stimulation
by viruses or polynucleotides.
• Is a glycoproteins.
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7.  Gamma interferon
• Immune interferon
• Produced by T-lymphocytes on stimulation by antigens or
mitogens.
• Is a glycoprotein.
• More concerned with immunomodulatory & antiproliferative
functions than with antiviral defence.
• It also differs from alpha & beta interferons in having a
separate cell receptor.
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8. GENERAL ACTION OF INTERFERONS
Tissue cell is infected by a virus
Releases interferon
Interferon will diffuse to the surrounding
cells & binds with receptor.
Production of a protein that prevents the
synthesis of viral proteins.
Prevents the spread of the virus
throughout the body.

9. PRODUCTION OF RECOMBINANT
INTERFERONS
 The complementary DNA(cDNA) was synthesized from mRNA
of a specific interferon.
 Inserted to a vector(plasmid) which is introduced into E.coli or
other cells.
 IFN can be isolated from culture medium. This is the basic
mechanism of producing recombinant IFNs.
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10. THERAPEUTIC APPLICATION OF IFNs
 Used for treatment of a large no:of viral diseases & cancers.
 Alpha IFNs Hepatitis B & C, chronic myeloid leukemia,
multiple myeloma, Kaposi’s sarcoma, melanoma.
 Beta IFNs Multiple sclerosis
 Gamma IFNs Chronic granulomatous disease, renal cell
carcinoma, chronic myeloid leukemia.
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11.  IFNs cause the death of cancerous cells by stimulating the
action of natural killer(NK) cells, a specialized form of
lymphocytes that can destroy cancer cells.
 Also used for the treatment of common cold & influenza. For
this purpose, IFNs can be used as nasal sprays.
 Common side effects of IFNs fever, malaise, fatigue,
muscle pains. High levels of IFNs cause kidney, liver, bone
marrow & heart toxicity.
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12. MARKETED FORMULATIONS
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BRAND NAME TYPE USE
Alferon N Human leukocyte–
derived interferon alfa-
n3
Genital and perianal
warts
Roferon-A Recombinant interferon
alfa-2a
Hairy cell
leukemia,AIDS
Intron A Recombinant interferon
alfa-2b
Hairy cell
leukemia,AIDS
Avonex, Rebif Recombinant interferon
beta-1a
Multiple sclerosis
Betaseron Recombinant interferon
beta-1b
Multiple sclerosis

13. INTERLEUKINES
 These are a large group of cytokines produced mainly by T cells,
although some are also produced by mononuclear phagocytes
(or) by tissue cells.
 The interleukins were first described as signals for
communication between white blood cells (leuk- from
leukocytes).
 Currently, it is well-known that these molecules are produced and
used as signalling molecules in many cells of the body, in
addition to immune cells.
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14.  Interleukins are secreted rapidly in response to an infectious agent,
it travels to its target cell and binds to the receptor molecule on the
cell’s surface that triggers a cascade of signals within the target cell
altering the cell’s behaviour.
 Interleukins represent a broad family of cytokines that are made by
hematopoietic cells and act primarily on leukocytes.
 Interleukins are stored at 2 – 8°c
 There are currently 35 well-known interleukins, however, there are
many more to be found and characterized.
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15. MECHANISM OF ACTION AND DOSE
 Mechanism of action;
 Immunotherapy with IL activates cytotoxic T-cell against RCC
 Dose and adminstration;
 Interleukin administered via intravenous (iv) injection as high
dose (usually defined as 600,000 – 720,000 units/kg).
 Lower dosage iv and subcutaneous IL-2 are also prescribed for
kidney cancer.
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16. TYPES OF INTERLEUKINES
Interleukin Primary Cell Structure Primary Activities
IL –1α/IL-1β Macrophages, NK Cells, B
cells
Inflammation
IL-2 T cells Activates T cells
IL-3 T cells Haematopoietic growth
factor
IL-4 T cells B cell growth
IL-5 T cells Eosinophil & B cell
growth
IL-6 T cell & fibroblasts Inflammation
IL-7 Stromal cells B & T cell growth
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17. Continued ……
Interleukin Primary Cell Structure Primary Activities
IL-8 Macrophages Chemoattractant for
neutrophils
IL-9 Activated T cells T cell growth &
Potentiates IgM, IgG & Ig
E
IL-10 B cells, T cells B cell growth / inhibition
of cytokine synthesis by T
cells
IL-11 Bone marrow stromal
cells
Haematopoietic co-factor
IL-12 Macrophages, B cells Induction of cell
mediated immunity
IL-13 T cells B cell growth
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18. PRODUCTION OF INTERLEUKINES
•Antigen is internalized and
degraded by the macrophages,
processed, and then presented on
the macrophage surface to the
resting T lymphocyte in conjunction
with an MHC molecule.
•Once the T-cell receptor engages the
MHC molecule plus antigen, the T
cell becomes activated and secretes
IL-2, IL-3, IL-4, IL-5, and IL-6.
•Interleukins 2,4, 5, and 6 enable
activated T cells to undergo clonal
expansion.
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19. THERAPEUTIC APPLICATION OF
INTERLEUKINES
 Used to enhance T-cell activation in immunodeficiency
diseases.
 Used in the treatment of cancers and other infectious diseases.
 Used to reduce graft rejection.
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20. MARKETED FORMULATIONS
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BRAND NAME TYPE USE
ALDESLEUKIN Recombinant human IL-
2 (rIL-2)
Chronic hepatitis C,
and Chronic hepatitis B
OPRELVEKIN Recombinant human IL-
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Hairy cell
leukemia,AIDS
MUPLESTIM IL-3 Hairy cell
leukemia,AIDS
SIGOSIX IL-6 Multiple sclerosis

21. CONCLUSION
Interferons(IFN) are cytokines that are responsible for the
activity of the immune system .
Interleukins are biologically active glycoproteins derived
primarily from activated lymphocytes and macrophages.
They mediate their action by binding with high affinity to
receptors which belong to a limited number of structural
families
Immunity are produced mainly by activated macrophages
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22. REFERENCES
 Johnson, Howard M., Fuller W. Bazer, Brian E. Szente, et al. "How
Interferons Fight Disease." Scientific American (May 1994): 68–76.
 Meulen, Volkerter, N. Stefan. "Inhibition of Major
Histocompatibility Complex Class II-Dependant Antigen
Presentation by Nutralization of Gamma Interferon Leads to
Breakdown of Resistance against Measles Virus-Induced
Encephalitis." Journal of Virology 75 (2000):1–13.
 Seppa, Nathan. "Interferon Delays Multiple
Sclerosis." Science News 158 (November 2000): 280–281.
 Interferons and Interferon Therapy, R.Priyanka et al /J. Pharm. Sci.
& Res. Vol. 6(12), 2014, 400-403
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