Breaking News
June 19, 2018 - Study combines gene editing and stem cell technologies to predict person’s risk for heart disease
June 19, 2018 - Weight loss of 20% or greater results in better outcomes for overweight, obese adults with knee osteoarthritis
June 19, 2018 - Alnylam Reports Updated Positive Results from Phase 1/2 Study of Lumasiran in Patients with Primary Hyperoxaluria Type 1 (PH1)
June 19, 2018 - Study predicts most people with earliest Alzheimer’s signs won’t develop dementia associated with the disease
June 19, 2018 - Abnormal sleep duration linked to metabolic syndrome in new study
June 19, 2018 - Researchers develop new method to preserve fertility in boys with prepubertal cancer
June 19, 2018 - Late onset of diabetes could be indicative of pancreatic cancer
June 19, 2018 - Skin tone makes big difference in diagnosis and treatment of dermatologic conditions
June 19, 2018 - After addiction, the long road back to good health
June 19, 2018 - High blood pressure could be an early sign of dementia
June 19, 2018 - Innovative drugs and new European treatment guidelines refine, improve MS therapy
June 19, 2018 - BIDMC scientists develop new tool to benefit patients with HCV-associated liver failure
June 19, 2018 - Diabetes diagnosis may come with increased risk of pancreatic cancer for African-Americans, Latinos
June 19, 2018 - Personalized Goals, Cash Motivate Heart Patients to Exercise
June 19, 2018 - Nipah Virus (NiV) | CDC
June 19, 2018 - Genomics offers new treatment options for infants with range of soft tissue tumors
June 18, 2018 - Study shows how moderate consumption of alcohol can protect the heart
June 18, 2018 - Gene editing technology predicts heart disease risk
June 18, 2018 - Who Will and Who Won’t Get the Flu?
June 18, 2018 - Research shows effective responses to online feedback
June 18, 2018 - Scientists to focus on big data and genetics to identify risk factors for dementia
June 18, 2018 - Ultrasound-based technology for assessing overweight adolescents with liver disease
June 18, 2018 - Osteochondral knee defect treated using cell technology
June 18, 2018 - New clinical trial finds no evidence to support use of tamsulosin for kidney stones
June 18, 2018 - Study demonstrates increased levels of gum disease in people at risk of rheumatoid arthritis
June 18, 2018 - Ebola & Marburg | NIH: National Institute of Allergy and Infectious Diseases
June 18, 2018 - Brains, eyes, testes: off-limits for transplants?
June 18, 2018 - Drug used to treat myelofibrosis can awaken ‘dormant’ lymphomas in the bone marrow
June 18, 2018 - New study focuses on best, cost effective practices to bridge treatment gap for brain disorders
June 18, 2018 - New study highlights predictors that prevent from achieving remission in early RA
June 18, 2018 - Neuroscientists map feeling of cool touch to the brain’s insula in mouse model
June 18, 2018 - Study highlights potential use of blood biomarkers as diagnostic tool for sleep apnea
June 18, 2018 - Eating plant-based diet can reduce risk for heart problems in people with type 2 diabetes
June 18, 2018 - Lenabasum has acceptable safety and tolerability in diffuse cutaneous systemic sclerosis
June 18, 2018 - Study shows link between risky opioid prescriptions and increased odds of death
June 18, 2018 - Bone density scans could help determine likelihood of cardiovascular disease
June 18, 2018 - Mechanical thrombectomy appears to be important therapy for acute stroke in very old patients
June 18, 2018 - Novel compound as effective as FDA-approved antibiotics for treating deadly infections
June 18, 2018 - Ironwood Pharmaceuticals Announces FDA Orphan Drug Designation for Olinciguat for the Treatment of Sickle Cell Disease
June 18, 2018 - Surgical outcomes equivalent whether physician anesthesiologist assisted by nurse anesthetist or AA
June 18, 2018 - Studies provide insight into molecular changes prior to onset of arthritis
June 18, 2018 - Dyaco unveils specialist medical and rehabilitation equipment range in the UK
June 18, 2018 - Engineers develop algorithm to monitor joints of patients with arthritis
June 18, 2018 - Women with higher vitamin D blood levels have lower risk for breast cancer
June 18, 2018 - New studies help elucidate role of sleep in chronic pain
June 18, 2018 - Researchers link red meat sensitivity spread by ticks with heart disease
June 18, 2018 - Research explores role of autopsy in cardiovascular medicine
June 18, 2018 - Motif Bio Submits NDA for Iclaprim
June 18, 2018 - NIH-funded researchers identify target for chikungunya treatment
June 18, 2018 - Negative emotions are murkier, less distinct in adolescence
June 18, 2018 - Gut microbiome may be potential contributor to depression, anxiety in people with obesity
June 18, 2018 - Canakinumab reduces gout rate by more than half in atherosclerosis patients, study shows
June 18, 2018 - What Does the Future Hold?
June 18, 2018 - FDA Approves Keytruda (pembrolizumab) for Treatment of Refractory or Relapsed Primary Mediastinal Large B-Cell Lymphoma (PMBCL)
June 18, 2018 - School cliques don’t always click
June 18, 2018 - Three experts from The Tinnitus Clinic contribute to major review on pulsatile tinnitus
June 18, 2018 - Unwieldy health costs often stand between teachers and fatter paychecks
June 18, 2018 - Link between frailty and mortality remains unchanged despite lower death rates, study finds
June 18, 2018 - Sleep disorders appear to be first sign of serious neurological diseases
June 18, 2018 - Childhood, adult obesity raise risk of developing hip and knee osteoarthritis
June 18, 2018 - Study unravels ‘blood stem cell niche’ puzzle
June 18, 2018 - People with heart problems do not take enough exercise, shows study
June 18, 2018 - Strong Link Identified Between T2DM and Parkinson’s Disease
June 18, 2018 - Early childhood interventions show mixed results on child development
June 18, 2018 - Chronic use of opioids related to increased risk of fracture nonunion
June 18, 2018 - AHA: Family Perseveres After Losing Father to Heart Attack
June 18, 2018 - Oral propranolol seems safe for infantile hemangioma
June 18, 2018 - New study gives explanation for food’s prominence in memory
June 18, 2018 - First photoactive drug to fight Parkinson’s disease
June 18, 2018 - Patient’s self-evaluation of personality disorders not as far off as previously perceived
June 18, 2018 - Upadacitinib Monotherapy Meets All Primary and Ranked Secondary Endpoints Versus Methotrexate in a Phase 3 Study in Rheumatoid Arthritis
June 18, 2018 - Vitamin B3 has a positive effect on damaged nerve cells in Parkinson’s patients
June 17, 2018 - Sunovion Announces FDA Acceptance of New Drug Application for Apomorphine Sublingual Film (APL-130277)
June 17, 2018 - Bid to beat obesity focuses on fat that keeps us warm
June 17, 2018 - Work Stress May Increase Risk of Developing Atrial Fibrillation
June 17, 2018 - New Zealand’s secret recipe for active school travel: The neighborhood built environment
June 17, 2018 - New Medscape report reveals sexual harassment rate of physicians
June 17, 2018 - Surgical Blood Transfusions Tied to Clot Risk
June 17, 2018 - CDC chief makes $375K, far exceeding his predecessors’ pay
June 17, 2018 - Education linked to higher risk of short-sightedness
Dengue immunity can provide protection from subsequent Zika infection

Dengue immunity can provide protection from subsequent Zika infection

image_pdfDownload PDFimage_print

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.

A study published the November 13, 2017, issue of Nature Communications by La Jolla Institute for Allergy and Immunology (LJI) investigator Sujan Shresta, Ph.D., now addresses interplay between dengue and ZIKV infections. It reports that 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,” says Shresta, an associate professor in LJI’s Center for Infectious Disease. “Our new work suggests that 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.

In theory, 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. But Shresta’s new work confirms what many vaccinologists are beginning to suspect, namely that protection against thus far intractable pathogens will likely require rallying both B-cells and T-cells.

Specifically, Shresta’s team created the first “sequential” mouse model mimicking dengue-then-Zika infection. To do that, they first infected mice genetically vulnerable to 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,” says Shresta. “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.

Jinsheng Wen, Ph.D., a professor at Wenzhou Medical University in Wenzhou City, China, was the study’s first author. Wen says the results from this work are a powerful lesson to vaccinologists currently wrestling with how to design an effective Zika vaccine: “Our work strongly suggests that a successful vaccine would need to include components to induce not only a B-cell response but also a T-cell response.” Today, anti-dengue vaccines that primarily evoke antibody responses are in clinical trials or starting to be licensed in certain countries but show only moderate success. And, there are no approved Zika vaccines, although the US government is partnering with pharmaceutical companies to develop candidates.

Shresta hopes work like hers will guide those efforts. “Approved vaccines for many diseases work by inducing antibody responses. But now we are dealing with problematic diseases, like dengue and Zika for which we cannot rely solely on raising antibodies. Certain pathogens are likely to also require a T-cell response.”

Tagged with:

About author

Related Articles