Discovery, Development and Optimization of Protein Drugs Lecturer: Michael Jeltsch, Faculty of Pharmacy, University of Helsinki

Course: MPHARM-002A/PROV-105A

11. & 17. September 2025

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Protein Drug Discovery & Development

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Table of contents

TOC

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Biology

Technologies

Protein hormones, growth factors & cytokines

Enzymes

Protein toxins

Protein vaccines (“recombinant vaccines”)

Antibodies

Protein drugs & biologicals

Examples of protein drugs

Discovery of protein drugs

Generation of protein drugs

today

next week

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Biologics

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Biologic = biological drug = biopharmaceutical =

A drug that is produced by/from living organisms or contains components of living organisms

Is this a good definition?

Think about the difference between synthetic and natural vitamins or the chemical synthesis of small proteins (Merrifield Solid‐Phase Peptide Synthesis)

…the definition is changing

The FDA definition of biologics includes meanwhile small peptides if they have >40 amino acids even if they are fully-synthetically produced.

…does it matter?

Yes, since the regulatory frameworks for small molecule drugs (SMDs) and biologics are different! E.g. semaglutide is officially not a biologic even though scientifically it is!

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Different types of biologics

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Vaccines

Cell therapy

Gene therapy

Proteins

Transplants

• Viruses
• DNA
• RNA

• Stemm cells�(autologous�Regenerative medicines�
• Autologous & allogenic cells (CAR-T)

• Antibodies:�polyclonal (“antisera”) & monoclonal
• Protein hor- mones, growth factors & cytokines
• Enzymes
• Protein toxins

• cell, organ & tissue transplants (bone marrow, blood, blood products, plasma-derived medicines
• fecal transplant
• xenotransplants
• biomaterials

• Live virus
• Killed virus
• Recombinant vaccines
• DNA/RNA vaccines
• Tolerogens

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Biologics

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Although biologics are the most rapidly growing drug class, they are not new,

but are among the oldest, truly effective medical interventions.

1st vaccination performed by Edward Jenner (1796), variolation perhaps as old as 500 AD

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Different types of biologics

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Any unifying theme?

Almost all biologics need to be “injected” with the exception of viruses.

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Different types of biologics: Proteins

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Vaccines

Gene therapy

Cell

therapy

Proteins

Transplants

• Antibodies:�polyclonal (“antisera”) & monoclonal
• Protein hormones, growth factors�& cytokines
• Protein vaccines
• Enzymes
• Protein toxins

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The four major protein drug classes

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• Growth factors/cytokines/protein hormones (mostly human proteins)�- Darbepoetin alfa, erythropoietin/”epo”, Aranesp^®: stimulate red blood cell production�- Insulin (Hypurin^®, Humulin^®, Novolin^®, Fiasp^®, etc.): hormone replacement therapy for diabetics
• Toxins (bacterial, animal, plant, etc. proteins) �- Ziconotide, ω-MVIIA, Prialt^®: pain killer�- Botulinum toxin, OnabotulinumtoxinA, BOTOX^®: muscle relaxant
• Enzymes & enzyme inhibitors�- TPA (Activase^®): dissolve blood clots�- DNaseI (Dornase α/Pulmozyme^®): dissolving cystic fibrosis mucus�- Adenosine deaminase (ADA): replacement therapy for SCID

The four major protein drug classes

• Antibodies (Abs) and antibody fusion proteins�- Tetanus antitoxin (anti-tetanus toxin polyclonal Ab, “antiserum”):�passive immunization/post exposure vaccination�- Avastin™, bevacizumab (anti-VEGF-A monoclonal Ab): cancer drug

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The four major protein drug classes

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1. Growth factors/cytokines/protein hormones (mostly human proteins)
2. Toxins (bacterial, animal, plant, etc. proteins)
3. Enzymes & enzyme inhibitors
4. Antibodies (Abs) and antibody fusion proteins
5. Biomaterials (collagen, gelatin, albumin, fibrinogen and other clotting factors, etc.)
6. Protein vaccines

The four six major protein drug classes

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The four major protein drug classes

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• Growth factors/cytokines/protein hormones (mostly human proteins)
• Toxins (bacterial, animal, plant, etc. proteins)
• Enzymes & enzyme inhibitors
• Biomaterials (collagen, gelatin, albumin,�Fibrinogen and other clotting factors, etc.)
• Protein vaccines
• Antibodies (Abs) and antibody derivatives�(fusion proteins, Ab conjugates)�

• Purification
• Modification

(limited)

• Generation
• Screening

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The six major protein drug classes

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Discovery vs. understanding

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(Most) early (protein) drugs:�1. Drug discovery → 2. Mechanistic understanding

Botox cleaves SNARE proteins, which mediate membrane fusion of vesicles that carry the neurotransmitter acetylcholine.

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Discovery vs. understanding

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(Most) current (protein) drugs:�1. Mechanistic understanding → 2. Drug discovery/development

10-15% of SCID (Severe Combined Immunodeficiency)�cases are caused by Adenosine deaminase (ADA) deficiency;

1. Metabolic poisoning by adenosine, dexyadenosine and dATP
2. dATP inhibits ribonucleotide reductase, which is needed to make DNA

ADA deficiency is curable since 1990 by retroviral gene therapy (drug: Strimvelis)!

commons.wikimedia.org/wiki/File:OSC_Microbio_19_04_SCID.jpg

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Discovery vs. understanding

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Target identification and validation for protein drugs does not really differ much from other drug types:

Making sure that the target is instrumental in the disease process (not only a byproduct of the disease)!

Alzheimer’s disease: Are β-amyloid plaques cause or consequence?

#1 β-amyloid plaques

cell damage & death

#2 unknown process

The antibodies lecanemab and donanemab “tag” the βA for removal, thus reducing plaques. While they successfully treat Alzheimer’s, #1 and #2 are not exclusive…

βA

upload.wikimedia.org/wikipedia/commons/4/4f/Alzheimer_dementia_%282%29_presenile_onset.jpg

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The four major protein drug classes

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• Growth factors/cytokines/protein hormones (mostly human proteins)�Replacement or supplementation therapy�- Insulin: hormone replacement therapy for diabetics
• Toxins (bacterial, animal, plant, etc. proteins)�Identification by screening, loss of biodiversity limits our future possibilities �- Botulinum toxin: muscle relaxant
• Enzymes�- TPA: dissolve blood clots�- DNaseI: dissolving cystic fibrosis mucus�- Adenosine deaminase: replacement therapy for SCID
• Antibodies (Abs)�Inhibition or neutralization therapy�- Tetanus antitoxin: passive immunization/post exposure vaccination�- Trastuzumab (anti-HER2 monoclonal Ab): cancer drug

drug discovery = basic biomedical research = understanding the molecular basis of disease

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Examples of protein drugs

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BOTOX

Bevacizumab

Avastin

Insulin

Erythropoietin

Interferon-ɑ

Herceptin

Trastuzumab

Aflibercept

Eylea

Aranesp

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Justinus Kerner (1786 – 1862)

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• Justinus Kerner, “inventor of BOTOX”
• After self experimentation, the German poet was in 1820 the first to suggest that botulinum toxin (“sausage poison”) could be used therapeutically to block the “sympathetic nervous system”
• This proposal became reality 150 years later, when various muscle spasms were successfully treated with local botulinum toxin injections.

https://doi.org/10.1212/WNL.53.8.1850

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BOTOX^®

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Botox^® (OnabotulinumtoxinA)

Botulinum toxins (BTs)

• A group of neurotoxic proteins produced by some species in the bacterial genus Clostridium.
• Size: ~150 kDa
• Botulinum toxin type A is the most lethal, naturally occurring toxin known to man.

https://doi.org/10.1016%2Fj.coph.2004.12.006

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BOTOX^®

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• Indications: different spasms, chronic migraine, strabismus (“crossed eyes”)
• Available in Finland: yes
• Company: Allergan, Inc (US) →
• Interesting: Used as a bioweapon
• Market introduction: late 1970s

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Unit definition

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• Google search results seem to avoid the scientific definition of the unit:

1 unit = mouse LD50 (female Swiss-Webster mice after single intraperitoneal injection)

• Mouse assay is the accepted “gold standard”, not a very handy assay (compare to Corona-PCR assay!)

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Heydrich assassination

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• BT has been used in warfare already early on and the most famous assassination where BT was allegedly used was of the Holocaust mastermind Reinhard Heydrich.
• Heydrich (Reichsprotektor of Bohemia- Moravia, was killed by the British intelligence service in 1942 in an attack with a specially prepared grenade.
• The claim that the grenade was altered to contain BT was never proven and is likely a hoax or exaggeration of the British bacteriologist Paul Fildes, who first succeeded weaponizing BT in 1941.

https://doi.org/10.1212/WNL.0000000000004066

Bundesarchiv, Bild 146-1969-054-16 / Hoffmann, Heinrich

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Insulin

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Insulin

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• First human successful treatment in 1922 with bovine (= cow) insulin (team Banting, Best & Collip)*
• Size: ~5.8 kDa
• Since 1982: human insulin (recombinant human insulin produced in E. coli bacteria)

https://doi.org/10.3389/fendo.2018.00613

*The fact that pancreatic insulin-containing extracts were able to treat diabetes had been discovered three times independently before (by George Ludwig Zuelzer in 1906, Israel Kleiner in 1915, Nicolae Paulescu in 1916).

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Isolation from natural sources vs. recombinant protein production

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• Protein purification from “natural” sources: “pig/cow insulin”, BOTOX

• Recombinant protein production, requires recombinant DNA technology (“genetic engineering”)

https://commons.wikimedia.org/wiki/File:Show_Pig_(18097041013).jpg

https://www.flickr.com/photos/56598064@N06/5283861272

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Recombinant DNA technology (simplified)

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WHY?

Because a recombinant production cell produces a s***load of protein compared to what can be found in natural sources

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Recombinant DNA technology (aka “Cloning”)

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en.m.wikipedia.org/wiki/File:The_Stokes_Twins_2021.png

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Protein drug examples

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Growth factors/cytokines/protein hormones/toxins

• Protein purification from “natural” sources (“pig/cow insulin”, BOTOX)
• Improvements by limited modification�

Antibodies (Abs)

• Generation
• Screening

PROV-409 & PROV-410 “Cloning Course” (Recombinant DNA technology in therapeutic protein engineering)

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Rapid-acting insulins by preventing dimerization/multimerization

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How are intermediate & long-acting insulins made?

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Insulin profiles

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Degludec Insulin (t_½ = 17-25h)

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How to “optimize” a protein: In-vitro/directed evolution

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Modified from https://commons.wikimedia.org/wiki/File:DE_cycle.png

In-vitro evolution

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Example: Making a super vascular endothelial growth factor (super-VEGF)

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DNA shuffling

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https://doi.org/10.1074/jbc.M511593200

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Synthetic or natural insulin? Nomenclature confusion

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Synthetic, man-made, human insulin: unclear usage, has historically been used to designate recombinant insulin as opposed to insulin from animal sources

Biosynthetic insulin: recombinant insulin

Fully synthetic insulin: by chemical synthesis in-vitro (“test tube”)

Insulin analogs (lispro, aspart, glulisine): recombinant insulin with modifications

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• 1963 first fully synthetic insulin (Meienhofer et al. 1963, Z Naturforsch 18b: 1120f)
• 1978 fully synthetic insulin (Giba-Geigy) used for therapy (Teuscher 1979, Schweiz Med Wochenschr 109: 743ff)
• 1978 first recombinant insulin from E. coli (Genentech, Goeddel et al. 1979, PNAS 76: 106ff)

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Human Insulin as Good as Costly Synthetic Versions

https://www.embibe.com/study/production-of-genetically-engineered-human-insulin-concept

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Modifications to “improve” proteins

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• Modify (reduce or increase) biological half-life: adding glycosylation (“glycoengineering”, most therapeutic proteins are naturally glycosylated as they are produced in eukaryotic cells), e.g. the erythropoietin homolog darbepoetin alfa

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Aranesp^® (Darbepoetin alfa)

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Aranesp^® (Darbepoetin alfa)

• Homolog of the endogenous protein hormone erythropoietin (“Epo”)
• Five point mutations to create NXT/S sites to increase the biological half life
• Stimulates red blood cell production

https://doi.org/10.1002/dta.1341

>sp|P01588|EPO_HUMAN Erythropoietin OS=Homo sapiens OX=9606 GN=EPO PE=1 SV=1

MGVHECPAWLWLLLSLLSLPLGLPVLGAPP

N T

RLICDSRVLERYLLEAKEAENITTGCAEHC

SLNENITVPDTKVNFYAWKRMEVGQQAVEV

VN T

WQGLALLSEAVLRGQALLVNSSQPWEPLQL

HVDKAVSGLRSLTTLLRALGAQKEAISPPD

AASAAPLRTITADTFRKLFRVYSNFLRGKL

KLYTGEACRTGDR

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Aranesp^® (Darbepoetin alfa)

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• Indications: several types of anemias
• Available in Finland: yes
• Company: Amgen (US)
• Interesting: The name erythropoietin was coined in Finland by Eeva Jalavisto & Eva Bonsdorf
• Market introduction: 2001

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Modifications to “improve” proteins

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• Modify (reduce or increase) biological half-life: adding glycosylation (“glycoengineering”, most therapeutic proteins are naturally glycosylated as they are produced in eukaryotic cells), e.g. the erythropoietin homolog darbepoetin alfa
• Improve biological activity (e.g. receptor binding affinities): e.g. consensus interferon is many times more effective than any single specific 𝛼-interferon (for Hepatitis C virus infection)

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Interferons

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The big IF (1980 US documentary film)

• The full video: https://www.youtube.com/watch?v=wgKOl-mM4dU
• The part that Finland played (starting at 16min 40sec): https://www.youtube.com/watch?v=wgKOl-mM4dU&t=16m40s

Link to the Flash Gordon comic strip

(due to copyright issues, the comic strip must not be embedded into this presentation)

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Consensus interferon

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Modifications to “improve” proteins

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• Modify (reduce or increase) biological half-life: adding glycosylation (“glycoengineering”, most therapeutic proteins are naturally glycosylated as they are produced in eukaryotic cells), e.g. the erythropoietin homolog darbepoetin alfa
• Improve biological activity (e.g. receptor binding affinities): e.g. consensus interferon is many times more effective than any single specific 𝛼-interferon (for Hepatitis C virus infection)
• Reduce size (proteins: high solubility, low permeability): reducing the size of antibodies (~140 kDa to ~25 kDa) for better tumor penetration

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Development of smaller E. coli-produced anti-VEGF-A protein drugs

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• More active ingredient/injection
• Better diffusion/reach

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Statistics “Name one biological drug”

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Immune system

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Immune system

Cell-mediated immunity

Humoral immunity

(proteins in body fluids):

• Antibodies
• Complement System
• Antimicrobial peptides

Innate immunity

Adaptive/Acquired immunity

• Antibodies (in humans)
• CRISPR/Cas systems (in bacteria)

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Antibodies: a part of our immune system

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Antibodies:

Highly specific protein drugs that the body generates on demand to fight everything non-self (mostly other non-self proteins)

Antigen: the molecule that the antibody targets

Immunogen: a molecule that can elicit an immune response (e.g. the generation of antibodies

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Antibodies: a part of our immune system

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• Largest pools of antibodies in the human body: 1) mucous membranes 2) blood
• Because each of us encounters many different immunogens, our blood con- tains a complex, unique, and constantly changing mixture of antibody proteins.

Antiserum*

Blood without cells & clotting factors. Antibodies (= immunoglobulins) are the 2^nd most abundant blood proteins after albumins, ~15mg/ml.

Polyclonal antibody

All immunoglobulins that react with a specific antigen

Monoclonal antibody

One specific Ig protein with a defined amino acid sequence

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And the 2025 winner is …

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Antibody (Immunoglobulin) structure (IgG)

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100-120

amino acids

antigen

binding

site

(paratope)

hinge region

Light chain

Heavy chain

C = constant

V = variable

complementary determing regions (CDR) 1-3

F_C region

(effector

function)

Fab region

(antigen

binding)

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Antibody in action

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antigen

antigen

Fc receptor

Effector cell (lymphocyte, mast cell, etc.)

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Antibody in action

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Neutralization of toxins and pathogens (“neutralizing/blocking” antibody)

Primary function of antibodies

SARS-CoV-2

Host cell membrane

ACE2

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Antibody classes

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IgG

secretory IgA

IgE

IgM

IgD

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Generation of antibody diversity

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• Millions of different antigens, but only 4 immunoglobulin genes: IGH (Ig heavy chain), IGK, IGL (light chains Ig Kappa and Ig Lambda) and IGJ (joining chain)
• Each of us has <4x10⁸ different antibodies, roughly the same magnitude as B cells in the blood
• How does the body generate so many different antibodies?

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V-D-J recombination (heavy chain, simplified)

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V-D-J recombination & class switching (heavy chain)

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Human heavy chain:

50 V�25 D

6 J

9 C

Human lambda light chain:

30 V�4 J

7 C

Human kappa light chain:

40 V�5 J

1 C

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Methods to generate antibody diversity

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1. Assembly of the heavy chain by recombination from V +D + J + C genes
2. Assembly of the light chain by recombination from V + J (+C), two different sets: kappa & lambda
3. Heavy and light chain combinations
4. Addition and deletion of nucleotides during recombination (“junctional diversity”)
5. Somatic hypermutation upon B cell activation by AID (activation-induces cytidine amidase) enzyme
6. Diversity between people (thousands of different alleles), Ig genes are the most polymorphic genes in humans

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Antibody drugs are not new!

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• Antibody drugs are the oldest efficient drug class that were purposefully developed.
• Effective antibody therapies have been developed and used in Germany as early as 1890 against deadly diseases like diphteria, tetanus, rabies and snake bites.
• Emil Behring (1854–1917) : Antiserum therapy (serum = blood without blood cells and without clotting factors*). Developed in guinea pigs, large-scale produced in horses.
• Still important for the production of anti- venom (snake, insect, scorpion) and anti-toxin (botulinum, anthrax, tetanus)
• Behringwerke (since 1952 part of Hoechst AG ➜ Sanofi-Aventis)

Illustration by Fritz Gehrke (1905)

• https://www.youtube.com/watch?v=I8ARFXkjAyo

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How are antibodies generated?

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Polyclonal antibody (“antiserum”) production

Ingredients for immunization (more or less unchanged for the last 100 years)

1. Antigen: (highly) purified protein, synthetic peptides (up to� ~100 aa)

2. Host: Rabbit, Mouse, Goat, Horse, Human (“convalescent� serum”)

3. Adjuvants (Freund’s complete adjuvant (FCA)*, aluminium� salts): to be mixed (mostly emulgated) with the antigen to� boost the immune response

4. Injection syringe for subq (intradermal, intraperitoneal,� footpad, intramuscular) injection

5. Pre-immune serum sample

6. Repeat injection (“booster”): e.g. up to 5 times in rabbits in 3-week-intervals, many different protocols

7. “Test bleeds” (e.g. starting from 2 weeks after 2nd booster) for analysis

8. For small hosts mostly “final bleed”, for larger animals (incl. humans): repeated blood donation/plasmapheresis

https://commons.wikimedia.org/wiki/File:Rabbit_in_the_farm-1.jpg

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How to make monoclonals?

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Köhler & Milstein 1975 Nature.

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mouse (murine) mAbs

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What happens if you inject mouse monoclonal antibodies (mAbs) into humans?

They are eliminated by an immune response!

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How to make human monoclonals?

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How to make human monoclonals?

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Image credit: Bioshore / CC BY-SA

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B cell receptor

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B cell receptor =

membrane-bound version of IgM

Igα

Igβ

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Engineered antibody formats

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Phage display of scFv fragments

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Phage display work-flow

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Drawbacks of phage display antibodies

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• No affinity maturation by somatic hypermutation�(counter-measure: mega-libraries)
• No elimination of antibodies with disfavorable physical attributes (aggregation, protease-sensitive, low protein expression levels, etc.)
• Converting scFv antibodies into IgG (or other) formats

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Ig-humanized mice

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Ig-humanized mice

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• XenoMouse: Cell Genesys/Amgen, https://doi.org/10.1038/nbt1337
• HuMab mouse: Gen­Pharm/Medarex/Bristol Myers Squibb
• VelociImmune mouse (Regeneron): piece by piece in-place replacement, https://doi.org/10.1073/pnas.1324022111
• OmniRat^® (OmniMouse^®/OmniChicken^®): OMT/Pfizer/Ligand: human V + rat C regions https://doi.org/10.1038/s41598-020-57764-7
• Alloy Gx™: Alloy Therapeutics Inc., royalty-free and proprietary, new player
• Kymouse™: Kymab Ltd./Wellcome Trust, human V + mouse C regions, https://doi.org/10.1038/nbt.2825
• Harbour Antibodies™: Harbour BioMed, normal (“H2L2”) and heavy chain only (“HCAb”), https://doi.org/10.1073/pnas.0601108103
• Trianni Mouse™: Trianni Inc., in-place replacement of V regions, https://www.nature.com/articles/d42473-018-00011-5

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Eliminating immune response to therapeutic mAbs

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https://en.wikipedia.org/wiki/Nomenclature_of_monoclonal_antibodies

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How to make human monoclonals?

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commons.wikimedia.org/wiki/File:Isolation_of_human_monoclonal_antibodies._.tif

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Big Business

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10.1186/s12929-019-0592-z

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Judah Folkman (1933 – 2008)

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Folkman, Dvorak, Ferrara

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1997

1971

Judah Folkman proposes the concept

of antiangiogenic tumor therapy

1992

1983

Napoleone Ferrara generates neutralizing

mouse antibodies against VEGF

​

​

Harold Dvorak isolates Vascular Endothelial Growth Factor (VEGF)

​

​

Clinical trials start with the humanized

anti-VEGF antibody (“bevacizumab”)

2004

Bevacizumab receives FDA approval

for treatment of colon cancer

©

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Avastin^®

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Avastin^® (Bevacizumab)

• Humanized mouse monoclonal antibody
• Suppresses the growth of blood vessels (“anti-angiogenic”)
• Hypothesis: Tumors need blood vessels to grow big

https://doi.org/10.1016/j.bbrc.2005.05.132

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Avastin^®

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• Indications: different cancers (colorectal, lung)
• Available in Finland: yes
• Company: Genentech (US) → Roche
• Interesting: This drug was predicted in 1971 by Judah Folkman
• Market introduction: 2004

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VEGF growth factors and receptors

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Antibody fusion proteins: Eylea^®

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Eylea^® (Aflibercept)

• Soluble VEGF-A receptor, works like Avastin (antibody)
• Suppresses the growth of blood vessels (“anti-angiogenic”)
• 3-part fusion protein from VEGFR-1(D2), VEGFR-2(D3), and IgG₁Fc

https://doi.org/10.1007/s40123-013-0015-2

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Antibody fusion proteins: Eylea^®

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• Indications: wet macular degeneration, diabetic retinopathy (~ growth of blood vessels from the choroid into the retina)
• Available in Finland: yes
• Company: Regeneron (US)
• Interesting: a successful “me-too-drug”
• Market introduction: 2011

https://www.flickr.com/photos/90767393@N00/1612670215

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Herceptin^®

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Herceptin^® (Trastuzumab)

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​

Antibody against ERBB2 (HER2)

• ErBB2 = tyrosine kinase receptor
• Overexpressed in ~15-30% of breast cancers
• One of the oldest mAbs still in use

https://www.gene.com/stories/her2/

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Herceptin^®

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• Indications: ERBB2⁺ breast cancer
• Available in Finland: yes
• Company: Genentech (US) →
• Interesting: ERBB2 is a receptor, but it has no known ligands, several biosimilars available since 2017
• Market introduction: 1998

10.3390/cancers11121826

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Biosimilars

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• Biosimilars copy biologics and are typically launched after the original drug’s patent-protection has ended.
• Different regulatory framework compared to original biologics and small molecule drug generics
• Lots of antibody drugs’ patent protections will end over the next years: lots of biosimilars
• Reducing prices and increasing availability of biologics

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Herceptin - The first personalized drug?

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Stratified medicine/Precision medicine

“One-size-fits-all” medicine

Personalized medicine

Jeltsch Lab & UH

What happens after a ligand or an antibody binds a receptor?

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What happens after an activating ligand has bound to a receptor?

1. Signaling
2. Receptor/ligand complex internalization (negative feedback loop) into endosomes
3. Signaling vs. dephosphorylation
4. Sorting of ligand and receptor in late endosomes
5. Dissociation of ligand and receptor in late endosomes, ubiquitylation
6. Recycling of receptor to the cell surface (via transport vesicles)
7. Targeting of ligand (and receptors) to lysosomes for degradation

Jeltsch Lab & UH

Attaching a “payload” to an antibody

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Problem:

All of these

groups occur

multiple�times in�most�proteins!

→Site-specific

conjugation!

Jeltsch Lab & UH

Trastuzumab → Trastuzumab emtansine (Kadcyla)

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• Current methods of antibody conjugation are not site-�specific and therefore inefficient and expensive (some antibodies get no cargo, others too much).
• The desired drug-to-antibody ratio (DAR) for Kadcyla is 3-4; heavily over- and underconjugated molecules needs to be purified away.
• Many companies are working on site-specific conjugation, where the cargo is attached to one or a few specific amino acid side chains.

Jeltsch Lab & UH

Kadcyla = Herceptin + toxic payload

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m-maleimidobenzoyl-N-hydroxysuccinimide ester (MBS, links to N-terminal amino group and lysines side chains on one end and cysteines at the other end, typical use: antibody-enzyme linking, heterobifunctional

�Example of heterobifunctional linker use in antibody production use: ADC trastuzumab emtansine (T-DM1, Kadcyla®, price ~70000 €/14 treatment cycles à 3 weeks).

Fair use

Jeltsch Lab & UH

Popular biologics

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jkjk

1. TNFalpha mAbs: Adalimumab, etc.
2. mAbs against migraine (calcitonin gene-related peptide & its receptor)
3. GLP-1 agonists: Ozempic, liraglutide, etc.

Jeltsch Lab & UH

Neurogenic or vasculogenic origin of migraine?

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10.1186/s10194-023-01644-8

Anti-CGRP monoclonal antibodies prevent migraine by blocking the calcitonin gene–related peptide (CGRP) pathway, which is a key driver of pain signaling and neurogenic inflammation in the trigeminovascular system.

Jeltsch Lab & UH

CGRP is one of several targets

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10.1186/s10194-023-01644-8

• CGRP inhibition does not stop the root cause of migraine (neurogenic), but interferes with migraine pain pathways.
• Amylin and its receptor are legitimate migraine drug targets (e.g. CGRP can bind one type of amylin receptor, amylin analogs can provoke headaches)

Jeltsch Lab & UH

Antibodies against migraine

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Calcitonin gene-related peptide (CGRP)-blocking monoclonal antibodies

• Target: CGRP
1. Fremanezumab (s.c)
2. Galcanezumab (s.c)
3. Eptinezumab (i.v)
• Target: CGRP receptor
• Erenumab (s.c.)
• Long biological half life in the blood: 1x monthly - 1x every 3 months
• On average a 35 % reduction in monthly migraine days (non-responders!)
• Alternatively Gepants (small molecule inhibitors of the CGRP receptor)
• To get a prescription in Finland, you need to have ≥2 weekly episodes + 2 prior failed other treatments (costs: 7-14k€/year, depending on the necessary dose)

Jeltsch Lab & UH

More to read and watch

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• Basics about B cells: https://www.ibiology.org/immunology/b-cell-development/#part-1
• Erichsen Geld und Gold E158, in German 😕: Impfstoff-Aktien vor hohen Verlusten (27.08.2020): https://podcasts.google.com/feed/aHR0cHM6Ly9lcmljaHNlbi5wb2RpZ2VlLmlvL2ZlZWQvbXAz
• Freakonomics Radio E430: Will a Covid-19 vaccine change the future of medical research? (27.08.2020): https://freakonomics.com/podcast/vaccine/
• The (in)complete list of all coronavirus vaccine development efforts: https://www.who.int/docs/default-source/coronaviruse/novel-coronavirus-landscape-covid-19-(3).pdf
• Very good, but old review about Ig-humanized mice: https://doi.org/10.1038/nbt1135

Jeltsch Lab & UH

Questions, contact

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• My laboratory: mjlab.fi (https://www.helsinki.fi/en/researchgroups/lymphangiogenesis-research-and-antibody-development)
• Core facility for protein production and purification: b3p.it.helsinki.fi
• jeltsch.org (private rumblings)
• jeltsch.org/science (private rumblings without the non-scientific stuff)
• Questions to: michael@jeltsch.org or michael.jeltsch@helsinki.fi, Consultation hours (also without appointment): Fri 9-12 Viikinkaari 5E, 4th floor, room 4051 (also via Zoom)
• This presentation: mjlab.fi/pddd, (jeltsch.org/teaching)

Jeltsch Lab & UH