Hemlibra for treating hemophilia

 The U.S. Food and Drug Administration today approved Hemlibra (emicizumab-kxwh) to prevent or reduce the frequency of bleeding episodes in adult and pediatric patients with hemophilia A who have developed antibodies called Factor VIII (FVIII) inhibitors. Reducing the frequency or preventing bleeding episodes is an important part of disease management for patients with hemophilia.

Hemophilia A is an inherited blood-clotting disorder that primarily affects males. According to the National Institutes of Health, hemophilia affects one in every 5,000 males born with the condition. Patients with hemophilia A are missing a gene which produces Factor VIII, a protein that enables blood to clot.

Patients may experience repeated episodes of serious bleeding, primarily into their joints, which can be severely damaged as a result. Some patients develop an immune response known as a FVIII inhibitor or antibody. The antibody interferes with the effectiveness of currently available treatments for hemophilia.

Hemlibra is a first-in-class therapy that works by bridging other Factors in the blood to restore blood clotting for these patients. Hemlibra is a preventative (prophylactic) treatment given weekly via injection under the skin (subcutaneous).

Patients treated with Hemlibra reported an improvement in hemophilia-related symptoms (painful swellings and joint pain) and physical functioning (pain with movement and difficulty walking) compared to patients who did not receive prophylactic treatment. Common side effects of Hemlibra include injection site reactions, headache, and joint pain (arthralgia).

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Dengue immunity can protect against Zika

Manifestations of Zika virus (ZIKV) infection differ drastically. Sometimes they are catastrophic, most notably when they cause microcephaly in some babies born to infected mothers. At other times, they are mild and fleeting, suggesting that unknown factors temper Zika infections' severity.

Recently, dengue virus emerged as a prime suspect because it shares many genetic and structural characteristics with ZIKV and is endemic in most of the regions affected by Zika's global spread.
Mice rendered immune to dengue show "cross-protection" from subsequent Zika infection and then identifies specific types of immune T-cells capable of defending against both viruses.

These revelations have profound implications for efforts to build a potent anti-Zika vaccine. In some parts of the world Zika is almost like a secondary infection. It has spread into Brazil/Latin America and is moving into places in Asia where people previously had dengue. Vaccines targeting either virus could be engineered to induce both T cell and antibody responses effective to protect people in these areas.

When one encounters a pathogen in real life, two arms of the immune system spring into action to neutralize it. In the so-called humoral response, B-cells begin to secrete specific antibody proteins, which latch onto and neutralize pathogens in tissue or blood. Simultaneously, a cell-mediated immunity system also becomes active, deploying cytotoxic T-cells to directly recognize and kill pathogen-infected cells.

The ideal vaccine might mimic both antibody and T cell responses to block an infectious disease. But in truth, most (26 of 28 vaccines currently licensed for human use) stimulate primarily a B-cell or antibody response, which in many cases is sufficient. Reseache team created the first "sequential" mouse model mimicking dengue-then-Zika infection. To do that, they infected mice genetically vulnerable to this family of viruses with dengue virus.

Those mice became sick, recovered from infection, and hence acquired immunity to dengue, presumably because viral infection had mobilized their immune B-cells, T-cells or both. The group then inoculated the same mice with ZIKV and waited to see if mice showed ZIKV symptoms. But overall, mice that had previously acquired dengue immunity showed protection against Zika, as evidenced by a reduced burden of ZIKV in blood and tissues, such as brain, liver or testis, compared to control mice not "pre-inoculated" against dengue.

These experiments suggest that the reason that some people infected with Zika do not come down with disease is due to prior exposure to dengue. This may explain why Zika is not passed to the unborn child of every pregnant woman in dengue-endemic countries exposed to virus. In a different experiment, the scientists isolated cytotoxic T cells from the blood of dengue-immune mice and infused them into normal mice, a procedure known as adoptive T-cell transfer.

 When infused mice were then infected with ZIKV, they also showed disease resistance, supporting the idea that the T-cell arm of the immune system can do the heavy lifting against ZIKV infection. A successful vaccine would need to include components to induce not only a B-cell response but also a T-cell response.
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Mylotarg for treating acute myeloid leukemia

Mylotarg (gemtuzumab ozogamicin) has been approved for the treatment of adults with newly diagnosed acute myeloid leukemia whose tumors express the CD33 antigen (CD33-positive AML).

AML is a rapidly progressing cancer that forms in the bone marrow and results in an increased number of white blood cells in the bloodstream.

Mylotarg is a targeted therapy that consists of an antibody connected to an anti-tumor agent that is toxic to cells. It is thought to work by taking the anti-tumor agent to the AML cells that express the CD33 antigen, blocking the growth of cancerous cells and causing cell death.

Common side effects of Mylotarg are fever, nausea, infection, vomiting, bleeding, low levels of platelets in the blood, swelling and sores in the mouth, constipation, rash, headache, liver damage, and low levels of certain white blood cells.
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Improved, safer Zika vaccine

Scientists have come up with better plant-based Zika vaccine that is more potent, safer and cheaper. It's based on key Zika protein. The vaccine works against a part of a Zika viral protein, called DIII, the part of the virus that infect people.

All flaviviruses have the envelope protein on the outside part of the virus. It has three domains. The domain III has a unique stretch of DNA for the Zika virus, this is used to generate a protective immune response that is unique for Zika.

Scientists carried out immunization experiments in mice, which induced antibody and cellular immune responses that have been shown to confer 100 percent protection against multiple Zika virus strains in a mouse.

The envelope protein were grew in bacteria, then switched to prepare the DIII protein domain in tobacco plants.
Producing plant-based vaccines, especially in tobacco plants, is safer than using chemical-based.

The protein-based vaccine uses the smallest and most unique part of the Zika virus that can still draw out a potent and good immune response.

Scientists made a pseudovirus- fake virus. The pseudovirus displays only the DIII part of the envelope protein on the surface. Making the full native envelope protein as the basis for a vaccine, it induced antibodies against DI, DII and the DIII domains of the protein.

Women were advised not to become pregnant because Zika virus can cause abnormalities in babies. It can cause
severe brain defect known as microcephaly, in which the head and brain don't develop properly.

It can also cause vision, hearing defects and learning disabilities associated with less severe infections. Gullian-Barre syndrome in adults  has also been linked to Zika virus.
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Antibody against cancer cell

 An antibody that can target regulatory T cells which in turn unleashes the immune system to kill cancer cells has been discovered.

The antibody decreased tumor growth in models of melanoma, glioblastoma and colorectal carcinoma, making it effective for cancer immunotherapy.

Tregs can be targeted by using an antibody that locks in on a molecular complex that's uniquely expressed on the cell surface of Tregs.

 anti-LAP antibodies is used to investigate the development of multiple sclerosis, but realized that it has implications on cancer.

Previous studies have shown that LAP+ cells are increased in human cancer and predict a poor prognosis. Being able to target these cells could offer a new way to treat the disease.

In the current study, the team used preclinical models to investigate how well anti-LAP antibodies could work in blocking the essential mechanisms of Tregs and restoring the immune system's ability to fight cancer.

They found that anti-LAP acts on multiple cell populations to promote the immune system's ability to fight cancer, including increasing the activity of certain types of T cells and enhancing immune memory.

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