9.14.2012

Talking of Chimps and hearing of Gerbils!

There is a lot of very useful information to be found via the internet. Of course it depends on where you look for your information.

Back in 2011, comments were filed by FASEB to the United States Fish and Wildlife Service about a petition to list all chimpanzees (captive, US based) as endangered.

I do not intend on arguing here about the status of Pan Troglodytes as being endangered or not, but I do want to show you some of the arguments put forward in the document as to what chimps are used for in research.

Note that according to FASEB at the time of writing there is a breeding moratorium in effect for chimpanzees owned by the National Institutes of Health (NIH). Currently, less than a thousand chimpanzees remain in NIH facilities in the U.S., and the number of animals available for research is decreasing by about 3% each year.

If you or a relative happens to suffer from or are afflicted by the below diseases or viruses, you may just want to DO THE RIGHT THING and voice your support towards animal research and that includes those of us that care about wild ape populations too!
FASEB feels that the status of captive chimpanzees should not be changed because this would both eliminate the important research needed to advance the public’s health and severely hamper research that is critical to the conservation of wild great ape populations.
Research involving chimpanzees has been and continues to be important for biomedical and behavioral research that will advance the public’s health. Because chimpanzees are the only animals susceptible to many diseases that afflict humans and share many of the same physiological characteristics, they have been crucial in the study of hepatitis, in the development and safety testing of monoclonal antibody therapies, in investigating other pathogens such as malaria, in the development of bioterrorism countermeasures, and in contributing to the conservation of wild great ape populations. This document will discuss some of the past, present and future needs for chimpanzees in research; identify some of the inaccuracies within the petition to reclassify captive chimpanzees; and provide information about the current status of the United States (U.S.) research chimpanzee population.
Hepatitis
Chimpanzees are the only animals other than humans susceptible to all five hepatitis viruses: A, B, C, D, and E [1]. It is well-documented that research on chimps led to the development of diagnostic tests for hepatitis A, B, and C and vaccines for both A and B [2-4]. Because of these diagnostic tests, the spread of these diseases through blood transfusion has virtually been eliminated. Due to the development of vaccines, hepatitis B is now nearly unknown in children born in the U.S., and hepatitis A rates in the U.S. have declined by 92% since the vaccine was introduced in 1995 [5, 6]. A 1997 National
Academy of Sciences report underscored the importance of the chimpanzee in the development of a vaccine for hepatitis B, concluding that they provided a source of virus and viral antigens and made it possible to evaluate the safety and the effectiveness of candidate vaccines [7].
Current work with chimpanzees continues to teach us a great deal about the immediate antiviral immune responses following hepatitis C infection [8]. These events can be studied in a way that is not possible in acutely infected humans, since human subjects remain asymptomatic directly following exposure to the virus. In addition, some chimpanzees that were infected with the B and C virus 30 years or more ago have developed cirrhosis and liver cancer similar to that seen in chronically infected humans [personal communication, Robert Purcell]. This underscores the importance of chimpanzees in the study of chronic hepatitis C.
One of the most important breakthroughs in finding a cure for hepatitis C has been the development of new antiviral therapies. Almost 200 million people suffer from chronic hepatitis C infection and are at risk for liver failure and liver cancer [9]. Many of the drugs currently in human clinical trials were tested in chimpanzees for safety and efficacy prior to their use in humans [personal communication, Robert Lanford]. The long awaited therapeutic validation of antisense technology came from a novel therapy for hepatitis C first tested in chimpanzees [personal communication, Robert Lanford]. Antisense technology is a therapy that inactivates genes responsible for disease. This same technology can now be applied to many other diseases, including cancer. Despite these successes, a vaccine to combat hepatitis C has yet to be developed, in part due to the complex nature of this particular virus and the large number of strains presents in different regions of the globe.
According to the Centers for Disease Control and Prevention (CDC), approximately 17,000 Americans are newly infected with the hepatitis C virus each year [9], and liver cancer due to chronic hepatitis C infection is now the most rapidly increasing cause of cancer death in the U.S. Current predictions suggest that the incidence of liver cancer (due primarily to chronic hepatitis C infection) will increase by four-fold over the next 10-20 years. A 2010 Institute of Medicine report on hepatitis and liver cancer concluded that studies to develop a vaccine to prevent chronic hepatitis C virus infections should continue [10]. Chimpanzee research will be essential in moving this work forward.
Monoclonal Antibodies 
Chimpanzees are of great importance in developing and testing monoclonal antibody therapies for autoimmune diseases and cancers such as non-Hodgkin’s lymphoma because their receptors and their cytokine profiles are virtually identical to humans [11-19]. These similarities make chimpanzees especially important for testing the safety of monoclonal antibodies [17].
The importance of this can perhaps best be underscored in the case of the TGN1412 monoclonal antibody [20]. This is a targeted humanized monoclonal antibody that was developed in Germany to treat multiple sclerosis, rheumatoid arthritis, and certain cancers. However, it nearly killed six men who voluntarily took the therapy during a 2006 Phase I clinical trial in the United Kingdom. Administration of the antibody evoked a cytokine storm that caused multi-organ failure in all six participants. This occurred despite the fact that the company and the UK’s Medicines and Healthcare Products Regulatory Agency deemed the product safe for human trials after testing in both rabbits and monkeys produced no harmful effects. However, it was not tested in the chimpanzee. Had the chimpanzee model been used, this life-threatening outcome might have been averted since the chimp and human immune systems are extremely similar [17, 21].

Other diseases
The scientific justification for the continued use of chimps is not limited to their value in hepatitis research and monoclonal antibody development. Despite the small number of publications on chimpanzees (0.25% of research utilizing animals), they are crucial in understanding disease progression, analyzing genetic similarities between chimps and humans, developing pharmaceutics, testing the safety and efficacy of pharmaceuticals, and understanding behavior (Figure 1). Chimpanzees have been and continue to be essential in studying the diseases listed below.

Malaria
Malaria is a parasitic infection that affects an estimated 190-311 million people a year with 700,000-1,000,000 deaths. Chimpanzees have been important for the development of in vitro assays for drug development [22], phylogenetic analyses [23], and vaccine development [24, 25].

Norovirus
Chimpanzees have been shown to be an excellent model for the study of and vaccine development for noroviruses [26]. Noroviruses are the most common cause of viral gastroenteritis in humans.

Poliovirus
Chimpanzees were instrumental in the study of and vaccine development for poliovirus [27-29]. Since development of the vaccine, polio has nearly been eradicated in humans.

Respiratory syncitial virus
Due to their genetic similarity to humans, chimpanzees have been and continue to be a useful mode for the study of respiratory syncitial virus (RSV) and vaccine development [30, 31]. RSV is a common respiratory virus that can cause severe and sometimes fatal infections in infants and the elderly.

Cytomegalovirus
The chimpanzee has the closest cytomegalovirus (CMV) variant to the human, thus making it an important animal model [32, 33]. Human CMV is the most significant viral cause of birth defects in industrialized nations and produces high morbidity and mortality rates in immunocompromised individuals.

Dengue fever
Due to changes in the earth’s climate, dengue fever, which was primarily restricted to tropical and subtropical regions, is now expanding into regions within the U.S. Between 2000 and 2007, reported cases of dengue fever within the U.S. have tripled, and there is currently no vaccine available to prevent it or therapy to treat it. Chimpanzees infected with the dengue virus develop high concentrations of neutralizing anti-viral antibodies [34], and since chimpanzee immunoglobulins are close to 98% homologous to those of humans [19], they make a good source of monoclonal antibodies [35] that could potentially be used to treat the disease.

Bioterrorism countermeasures
Research involving chimpanzees could also be vital for the development of countermeasures against bioterrorism attacks. An October 2011 "Bio-Response Report Card" by the bipartisan Weapons of Mass Destruction Terrorism Research Center indicated that the U. S. is unprepared to respond to a global outbreak of a deadly virus for which we have no medical countermeasures [36]. The U.S. was given an F (fails to meet expectations) on medical countermeasure development and production for a global, contagious biological event. In an emergency, rapid access to a research population of chimpanzees could be needed in order to quickly develop and test prophylactic and therapeutic strategies against these dangerous agents to ensure the safety of our population.
The use of chimpanzees in biosecurity preparedness is evident in two recent publications. Chen and colleagues at the National Institute of Allergy and Infectious Disease used chimpanzees to develop neutralizing antibodies against the vaccinia virus (smallpox) [37, 38]. These chimpanzee studies were important because they provided a mechanism to create immediate passive immunity should we be attacked using smallpox as a biological weapon.

Research for wild ape populations
Chimpanzees are susceptible to many of the same pathogens as humans, including the common cold, pneumonia, poliomyelitis, tuberculosis, chicken pox, respiratory disease, and influenza among others. As such, they are useful models to study the pathogenesis of the diseases and potential therapeutics. Moreover, due to increased ecotourism in Africa, the likelihood of humans transmitting diseases to the wild ape populations is escalating [39]. Continued biomedical research will not only benefit humans but also conservation efforts to sustain the great ape population.

Ebola
In February 2011, researchers at the New Iberia Research Center in Louisiana began a safety study on chimpanzees in order to test an Ebola vaccine for wild gorillas and chimpanzees [40]. The researchers inoculated six chimpanzees and were able to establish that the Ebola vaccine elicits a strong immune response. The urgency of these studies is highlighted by the fact that Ebola is ravaging the great ape population in the wild and has killed about one-third of all gorillas [41-43]. The first controlled vaccine trial on wild apes began in April 2011 [44].

Heart disease
Heart disease is a major cause of morbidity and mortality in the human and chimpanzee population. Sudden cardiac death has been shown to be the predominant cause of death in captive chimpanzee populations [45, 46]. Lammey and colleagues have implanted electrocardiogram recorder to investigate and diagnose cardiac arrhythmias in unanesthetized chimpanzees and have identified biomarkers to detect cardiovascular and renal disease in chimpanzees [45, 47].

Immunodeficiency viruses
Until recently, it was thought that SIVcpz, the immediate precursor to human immunodeficiency virus type 1 (HIV-1), was not pathogenic (i.e., did not cause death) in chimpanzees. Of late, however, it has been demonstrated that wild chimpanzee populations have been dying as a result of infection with this virus [48-50]. Previous research using the chimpanzee as a model for HIV may be beneficial in understanding the pathogenesis of SIVcpz and developing therapeutics.


To read the text in full and find the references follow this link.

Of course if you do not believe animal research leads to medical advancement for humans and or other animal species, the following may not be of interest to you either.
However for those of us to whom it does matter please do take a look at how stem cells are being used to improve hearing using gerbils. A small step but a leap towards getting closer to new or improved therapies. Thank You Marcelo Rivolta et Al ! 

http://www.timescolonist.com/health/Stem+cells+used+restore+hearing/7235648/story.html

and

http://www.nature.com/news/human-embryonic-stem-cells-restore-gerbil-hearing-1.11402












 

2 comments:

  1. Journal of Pharmaceutics and Drug Research is an international multidisciplinary open access journal founded by Ke-He Ruan. This Journal is chiefly devoted to publishing high-quality papers focused on all aspects of pharmaceutics and drugs that are critical to the discovery and development of new drugs and therapies.
    Pharmaceutics and Drug Research

    ReplyDelete
    Replies
    1. Welcome and good luck 🍀 with your endeavours. Impressive editorial board!

      Delete