Nobel Prize in Physiology or Medicine 2008: Discovery of HPV and HIV

This note covers the Nobel Prize in Physiology or Medicine 2008: who won it, how Harald zur Hausen linked human papilloma virus to cervical cancer, how Françoise Barré-Sinoussi and Luc Montagnier discovered HIV, how both discoveries unfolded, why they matter and quick facts for exams.

What was the Nobel Prize in Physiology or Medicine 2008 awarded for?

The Nobel Assembly at Karolinska Institutet split the prize between two separate discoveries about viruses that cause serious human disease. Harald zur Hausen received one half of the prize "for his discovery of human papilloma viruses causing cervical cancer".

Françoise Barré-Sinoussi and Luc Montagnier shared the other half "for their discovery of human immunodeficiency virus".

In plain words, this means one scientist showed that a common wart-causing virus, in certain forms, can trigger cervical cancer in women, while two other scientists identified the virus that causes AIDS.

Both findings came from patient studies: the viruses were hunted for and found inside diseased human cells.

The official name of the award is the Nobel Prize in Physiology or Medicine, and it is given each year by the Nobel Assembly at Karolinska Institutet in Sweden.

Who are the laureates?

Harald zur Hausen

Harald zur Hausen was born on 11 March 1936 in Gelsenkirchen, Germany, and died on 28 May 2023 in Heidelberg, Germany.

At the time of the award he worked at the German Cancer Research Center in Heidelberg, where he had been Chairman and Scientific Director. He received one half of the prize.

He spent over a decade proving that specific types of human papilloma virus (HPV), rather than the herpes virus that most researchers suspected, cause cervical cancer, and he isolated the cancer-causing types HPV16 and HPV18.

Françoise Barré-Sinoussi

Françoise Barré-Sinoussi was born on 30 July 1947 in Paris, France. At the time of the award she headed the Regulation of Retroviral Infections Unit, Virology Department, at the Institut Pasteur in Paris. She received one quarter of the prize.

Working with Luc Montagnier, she detected signs of a new retrovirus in lymph node cells from patients with early acquired immunodeficiency, a virus later named HIV.

Luc Montagnier

Luc Montagnier was born on 18 August 1932 in Chabris, France, and died on 8 February 2022 in Paris, France. At the time of the award he led the World Foundation for AIDS Research and Prevention in Paris.

He received one quarter of the prize. He and Barré-Sinoussi together isolated and characterised the retrovirus, showing it behaved like no previously known human virus.

What problems were these discoveries trying to solve?

By the 1970s, cervical cancer was recognised as the second most common cancer among women worldwide, and doctors suspected a sexually transmitted infection was behind it.

The dominant theory blamed the herpes simplex virus, but zur Hausen could not find herpes DNA in tumour samples even though his testing method had worked well for other viruses, including Epstein-Barr virus in other tumour types.

He proposed instead that an unnoticed virus, human papilloma virus, was responsible, even though at that time HPV was known mainly as the cause of harmless skin warts rather than cancer.

His approach added a strict rule to the classic test for proving a virus causes a disease: he insisted that the viral genetic material must be consistently present and active inside the tumour, not merely found nearby.

At almost the same time, in 1981, doctors in the United States began reporting a baffling new illness in young, previously healthy men: rare cancers and infections that normally only struck the very old or people on immune-suppressing drugs.

The Nobel Prize's popular information page notes this was first called Gay Related Immunodeficiency before being renamed Acquired Immune Deficiency Syndrome, or AIDS, in 1982.

Because the disease could spread through sexual contact, blood transfusion and from mother to child, researchers suspected a virus, and a global search for the cause began.

Both puzzles needed the same basic tool: a reliable way to prove that a specific, previously unknown virus was hiding inside sick human cells, without being able to simply grow large amounts of it in the laboratory the way earlier viruses had been studied.

In both cases, the usual methods of virus-hunting, such as growing the organism in culture and watching for obvious damage, did not readily work, so each team had to build an indirect route to proof from small, patchy clues.

How did zur Hausen find the cervical cancer virus?

Zur Hausen could not grow HPV in culture, so he devised an indirect method. He reasoned that if a virus caused the tumours, a piece of its genetic material, its DNA, would be sitting inside the chromosomes of the cancer cells, even if it was not actively making new virus particles.

1. He prepared short, single-stranded segments of DNA copied from viruses already known from plantar warts, to use as a chemical "bait".
2. He mixed this bait with DNA extracted from tumour samples, relying on the fact that matching DNA strands pair up with each other, a process called hybridisation.
3. Early tests on genital warts and cervical tumours gave no match, so he loosened the matching rules (low stringency hybridisation) to allow imperfect pairing between related virus types.
4. After roughly ten years of repeated searching, this approach pulled out a new type of viral DNA from cervical tumour cells, which he described as HPV16 in 1983.
5. In 1984 he identified and cloned a second cancer-linked type, HPV18, from other patients' tumours.

Draw a strand of tumour cell DNA and a short labelled "bait" DNA strand approaching it; show the bait pairing up only where the sequences match, like a hook catching a loop, to represent how zur Hausen searched for HPV DNA inside cancer cells.

Later work explained why only some infections turn cancerous. Two viral genes, called E6 and E7, are the culprits: E7 switches off a cell gene that normally controls cell division, and E6 blocks a protective protein called p53 that would otherwise force an abnormally dividing cell to self-destruct.

With both safety checks disabled, infected cells can divide unchecked, and over ten to thirty years this can develop into a tumour.

How did Barré-Sinoussi and Montagnier find HIV?

Barré-Sinoussi and Montagnier suspected a retrovirus, a type of virus that carries its genes as RNA rather than DNA and must convert that RNA into DNA using an enzyme called reverse transcriptase before it can enter a host cell's genome.

1. They obtained lymph node samples from a patient showing early signs of the immune deficiency, since lymph nodes were known to hold far more virus than blood.
2. They cultured lymphocytes from the sample in dishes, treating the cells to encourage them to behave as if inflamed, which boosted any virus production.
3. Every third day for two weeks they centrifuged the culture fluid and tested it for reverse transcriptase activity, a telltale sign of a retrovirus.
4. They confirmed the enzyme needed magnesium ions rather than manganese ions, which the popular information page says ruled out a mitochondrial enzyme and pointed clearly to a true retrovirus.
5. Using an electron microscope they watched new virus particles budding directly from the surface of infected cells, revealing its shape as that of a lentivirus, a "slow" virus.

They found the virus infected and fused together a type of white blood cell called T helper lymphocytes, explaining why patients lost this vital immune cell type.

Unlike earlier cancer-causing retroviruses, this new virus did not make cells grow uncontrollably; instead it needed the cell to be active in order to replicate, and it killed the cells it infected.

They published their results in 1983, first calling the virus Lymphadenopathy Associated Virus, and by 1984 had traced it in sexually infected patients, haemophiliacs, mother-to-infant cases and transfusion patients. It was later renamed HIV-1 by an international taxonomy group.

Draw an infected T lymphocyte with small round virus particles pinching off, or "budding", from its outer membrane, to show how Barré-Sinoussi and Montagnier observed new HIV particles forming under the electron microscope.

How did the discovery unfold?

Why does it matter?

Zur Hausen's discovery made HPV16 and HPV18 available to other scientists, which the sources say paved the way for prophylactic vaccines that give high protection against infection by these two high-risk types.

The committee noted the vaccines may also reduce the need for surgery and the global burden of cervical cancer, which affects around 500,000 women a year.

The HIV discovery allowed rapid cloning of the virus's genome, which led to blood-screening tests that limited the spread of infection through transfusions, and to the development of several classes of antiretroviral drugs.

The sources state that combined prevention and treatment have substantially cut the spread of the disease and dramatically raised life expectancy for treated patients, although no complete cure exists and the virus can still hide inside host cell DNA, making eradication difficult even after long-term treatment.

Open questions mentioned in the sources include how long vaccine protection against HPV will last and whether other HPV strains might become more important causes of cancer as the main ones are controlled by vaccination.

The sources also describe HIV as having produced an unprecedented global pandemic: around 60 million people have been infected and around 25 million have died of AIDS, with the epidemic now most prevalent in sub-Saharan Africa, where heterosexual transmission dominates and young women are particularly vulnerable.

Cloning the virus also allowed scientists to trace its origins, with later studies suggesting that the virus passed from chimpanzees to humans in West Africa, probably through contact with hunted animals, long before the epidemic was recognised.

The sources further note that antiviral drugs have become steadily cheaper, which has widened access in poorer countries, even though distribution problems and gaps in patient knowledge meant that not everyone who needed treatment could obtain it.

How does this connect to what you study?

This prize links directly to biology topics on viruses, the immune system and cell division.

Human papilloma virus and HIV are both shown here as agents that hijack a host cell's own genetic machinery, HPV by switching off tumour-suppressing controls, and HIV by targeting the immune cells meant to fight infection.

Understanding DNA hybridisation, the pairing of matching genetic sequences, also connects to any lesson on how genetic material is identified and compared in a laboratory, since the same base-pairing rule, A with T and C with G, underlies many modern genetic tests.

The idea that a virus's genes can sit inside a human chromosome for years without producing new virus particles is a useful way to understand how infections can cause long-term disease rather than only short, obvious illness.

Lessons on the cell cycle and tumour suppressor proteins, such as p53, are brought to life by the HPV story, because the E6 and E7 viral proteins work by directly disabling the very controls that a biology course describes as keeping normal cell division in check.

Similarly, any study of the immune system, including the roles of lymphocytes and T helper cells, is strengthened by seeing how HIV causes disease precisely by destroying the white blood cells that would otherwise organise the body's defence.

The idea of a retrovirus, which copies its RNA into DNA using reverse transcriptase before inserting itself into a host genome, also gives a concrete example of how genetic information can flow in directions other than the usual DNA-to-RNA-to-protein pattern taught in molecular biology.

Finally, the development of HPV vaccines and HIV blood tests shows students how basic laboratory discoveries about a virus's structure can be translated, over years, into public health tools used around the world.

Quick facts for exams

The Nobel Prize in Physiology or Medicine 2008 was announced on 6 October 2008 by the Nobel Assembly at Karolinska Institutet.

It was divided between Harald zur Hausen, who received one half for discovering that human papilloma viruses cause cervical cancer, and Françoise Barré-Sinoussi and Luc Montagnier, who jointly received the other half for discovering the human immunodeficiency virus (HIV).

Zur Hausen worked in Germany; Barré-Sinoussi and Montagnier worked in France. The prize carried a cash amount of 10,000,000 Swedish kronor, split according to each laureate's share.

Note: Source. The prize facts in this note are from the Nobel Prize's official site, nobelprize.org.

Glossary

• Human papilloma virus (HPV) — a family of viruses, some types of which can cause skin or genital warts, and certain high-risk types of which can cause cervical cancer.
• Retrovirus — a virus whose genetic material is RNA, which it converts into DNA inside a host cell using reverse transcriptase.
• Reverse transcriptase — an enzyme that copies RNA into DNA, used by retroviruses including HIV to enter a host cell's genome.
• Hybridisation — a laboratory technique in which a known piece of DNA is used to find and pair with a matching, unknown DNA sequence.
• Lentivirus — a slow-acting subgroup of retroviruses, of which HIV is the first type found to infect humans.
• AIDS — Acquired Immune Deficiency Syndrome, the disease caused by HIV infection destroying immune cells.
• T helper lymphocytes — white blood cells essential to the immune system that are the main target destroyed by HIV.
• E6 and E7 genes — two HPV genes that disable a cell's normal division controls and protective proteins, allowing uncontrolled cell growth.
• p53 — a cell protein that normally forces abnormally dividing cells to self-destruct, blocked by the HPV E6 protein.
• Prophylactic vaccine — a vaccine given to prevent infection before it occurs, as developed against high-risk HPV types.
• Cervical cancer — cancer of the cervix, described in the sources as the second most common cancer among women worldwide.
• HIV-1 — the official name given in 1985 to the human immunodeficiency virus discovered by Barré-Sinoussi and Montagnier.

Common errors and misconceptions

• Misconception: HPV always causes cancer. Correct: most HPV infections clear up on their own and only certain high-risk types are linked to cervical cancer.
• Misconception: zur Hausen discovered HIV. Correct: zur Hausen discovered the cancer-causing papilloma viruses; HIV was discovered separately by Barré-Sinoussi and Montagnier.
• Misconception: the 2008 prize was for a vaccine. Correct: the prize recognised the discovery of the viruses, which later made vaccine and drug development possible.
• Misconception: HIV was grown easily in the laboratory from the start. Correct: the scientists had to repeatedly add fresh healthy cells to keep infected cultures alive long enough to study the virus.
• Misconception: AIDS can now be completely cured. Correct: the sources state there is no complete cure, though antiviral drug combinations allow a near-normal lifespan.
• Misconception: all three laureates shared the prize equally. Correct: zur Hausen received one half, while Barré-Sinoussi and Montagnier shared the other half equally.

Exam-style questions with model answers

Q1. Name the three laureates of the Nobel Prize in Physiology or Medicine 2008. [2 marks]

1. Harald zur Hausen, Françoise Barré-Sinoussi and Luc Montagnier received the 2008 prize for their virus discoveries.

Q2. What was Harald zur Hausen's citation for the prize? [2 marks]

1. His citation was "for his discovery of human papilloma viruses causing cervical cancer".

Q3. Explain the hybridisation technique zur Hausen used to find HPV DNA. [4 marks]

1. Zur Hausen prepared short single-stranded DNA segments copied from known wart viruses to act as bait.
2. He mixed this bait with DNA from tumour cells, relying on matching DNA strands pairing together.
3. When exact matches failed, he loosened the matching conditions, called low stringency hybridisation, to catch related but not identical virus DNA.
4. This approach eventually isolated the new cancer-linked viral DNA called HPV16 from cervical tumours.

Q4. How did Barré-Sinoussi and Montagnier confirm they had found a retrovirus? [4 marks]

1. They cultured lymph node cells from a patient with early immune deficiency and tested the fluid for an enzyme called reverse transcriptase.
2. Finding this enzyme active was a direct sign of retrovirus replication inside the cultured cells.
3. They confirmed the enzyme needed magnesium ions rather than manganese ions, ruling out a non-retroviral source.
4. Electron microscopy then showed new virus particles budding from the infected cells, confirming it as a retrovirus of lentivirus shape.

Q5. Discuss how the discoveries of HPV and HIV changed medical treatment and prevention. [5 marks]

1. Zur Hausen's isolation of HPV16 and HPV18 made these viruses available to other scientists, who developed prophylactic vaccines giving strong protection against the two types responsible for about 70 percent of cervical cancers.
2. This has reduced reliance on surgery and offers hope of lowering the global burden of cervical cancer, which affects roughly 500,000 women a year.
3. Barré-Sinoussi and Montagnier's discovery of HIV allowed rapid cloning of its genome, which revealed details of how the virus replicates and interacts with host cells.
4. This knowledge led to blood-screening tests that limited transfusion-related spread and to the development of several classes of antiretroviral drugs.
5. Combined prevention and treatment have substantially cut disease spread and dramatically increased life expectancy for people living with HIV, although no complete cure yet exists.

Q6. What genes allow high-risk HPV to cause cancer, and how do they work? [4 marks]

1. Two viral genes, E6 and E7, are responsible for the cancer-causing activity of high-risk HPV types.
2. The E7 protein switches off a cell gene that normally controls how often the cell divides.
3. The E6 protein blocks the protective protein p53, which would normally force an abnormally dividing cell to self-destruct.
4. With both safety mechanisms disabled, the infected cell can divide uncontrollably and, over years, may develop into a tumour.

Q7. State the affiliation of each 2008 Medicine laureate at the time of the award. [2 marks]

1. Zur Hausen was at the German Cancer Research Center in Heidelberg, Barré-Sinoussi was at Institut Pasteur in Paris, and Montagnier led the World Foundation for AIDS Research and Prevention in Paris.

Q8. Why was it initially difficult to identify the cause of AIDS? [3 marks]

1. The disease produced a wide range of unusual infections and cancers that did not obviously point to one single cause.
2. Patients included groups as varied as homosexual men, haemophiliacs and recipients of blood products, making the pattern of spread unclear at first.
3. No virus had yet been isolated, so scientists had to hunt for an unknown retrovirus using indirect laboratory signs such as enzyme activity.

Key takeaways

• The 2008 Nobel Prize in Physiology or Medicine recognised two separate virus discoveries affecting global health.
• Harald zur Hausen proved that certain human papilloma virus types cause cervical cancer, after a decade of persistent research.
• Françoise Barré-Sinoussi and Luc Montagnier discovered HIV, the retrovirus responsible for AIDS, in 1983.
• Zur Hausen's work enabled the development of prophylactic vaccines against high-risk HPV types.
• HIV's discovery allowed blood screening and the development of antiretroviral drugs that greatly extend patients' lives.
• Both viruses attack by interfering with normal cell control, HPV by disabling tumour suppression and HIV by killing immune cells.
• Despite major progress, there is still no complete cure for AIDS and open questions remain about long-term HPV vaccine protection.

Test yourself

Who shared the other half of the 2008 Medicine prize with Harald zur Hausen?

Françoise Barré-Sinoussi and Luc Montagnier shared the other half for discovering the human immunodeficiency virus.

What technique did zur Hausen use to search for HPV DNA in tumour cells?

He used DNA hybridisation, pairing bait DNA strands from known viruses with matching viral DNA in tumour samples.

What enzyme signalled that Barré-Sinoussi and Montagnier had found a retrovirus?

They detected reverse transcriptase activity, the enzyme retroviruses use to convert RNA into DNA.

Which two HPV types are most strongly linked to cervical cancer?

HPV16 and HPV18 are the two types found in about 70 percent of cervical cancer cases.

What cell type does HIV mainly destroy?

HIV mainly infects and kills T helper lymphocytes, white blood cells essential to the immune system.

What major medical advance resulted from the HPV discovery?

The discovery led to the development of prophylactic vaccines that protect against infection by high-risk HPV types.

Where were Barré-Sinoussi and Montagnier based when they made their discovery?

They worked at the Institut Pasteur in Paris, France, where they isolated the new retrovirus from patient lymph nodes.

Is there currently a complete cure for AIDS, according to the sources?

No, there is no complete cure, though antiretroviral drug combinations allow patients to survive for a near-normal lifespan.