Microbes in the News Assignment: Post #3

Article and link: “Too Clean for Our Children’s Good? The Checkup’ by Perri Klass, MD, The New York Times, April 17, 2017.

https://www.nytimes.com/2017/04/17/well/family/too-clean-for-our-childrens-good.html?rref=collection%2Ftimestopic%2FBacteria&action=click&contentCollection=science&region=stream&module=stream_unit&version=latest&contentPlacement=3&pgtype=collection&_r=0

Summary: This article talks about the many various ways in which our children are protected from interaction with microbes, including giving birth by caesarian section, bottle-feeding, and possible exposure to antibiotics. Such protection on the one hand affords protection from disease but on the other hand offers greater risk that children may experience complications of the “built environment.’ It is a concern that living in such a clean, controlled environment could lead to an underdeveloped immune system and subsequent health problems which may have otherwise been avoidable had the body been exposed to a diverse array of microbes at a young age. In order to combat this problem, it is recommended that young children be introduced to these microbes in the outside environment through “controlled exposures’ in the form of either “natural exposure’ consisting of interaction with their environment or through a type of vaccine yet to be developed.

 

Connections: This article include discussion of the development of the human microbiome, its importance in the overall health of an individual, the avenues by which children are typically first exposed to microbes, and also the concept of vaccination with microbes in order to improve health. All of these are topics which have been mentioned or discussed over the course of the semester.

 

Critical analysis: I liked the contrast that the author provided between the microbes found outdoors as opposed to those found within the “built environment.’ While I had naturally assumed that the inside of a house or apartment may be “cleaner’ than the outside world, I had not given much thought to the members of the microbial populations to be found in each of the two environments; in reality, the inside of a dwelling is not necessarily any more microbe-free than the outside, it is instead simply inhabited by a different, and possibly narrower, variety of microbes. I did not detect anything scientifically inaccurate or confusing in this article, and think that it did perform an adequate job in relaying this information to the public. The author did not get too technical in any of their explanations, yet clearly stated the anticipated problem, reasons behind that belief, and also the possible solutions to the problem.
Question: Are researchers suspecting that the health problems mentioned are primarily due to inadequate exposure to pathogenic bacteria? Or do interactions with the non-pathogenic bacteria also play a role in shaping the immune system of children? What kinds of “natural exposures’ are parents advised to pursue in order to assist their child’s immune system to develop properly?

A2: Microbes in the News!

Fungi have enormous potential for new antibiotics

https://www.eurekalert.org/pub_releases/2017-04/cuot-fhe041917.php

Summary: This article explores recent research into the genome of 24 different fungal species in order to identify antibiotic and other bioactive compound production genes. This study has resulted in the discovery of over 1000 pathways for generation of bioactive compounds with pharmaceutical application.

Connection:  The article could be characterized as part history of the use of antibiotics and the rise of antibiotic resistance. We have at length discussed the prevalence and mechanisms for bacterial antibiotic resistance as well as the known pathways for antibiotic production in microbes like fungi.

Critical Analysis:  The studied referenced in the article shows the promise of new antibiotic and even anti-cancer medications as a result of identifying these genomic pathways in fungi. The researchers believe that the knowledge gained from these sequences will also improve the efficiency of production and efficacy of existing antibiotics. At one point in the article, they refer to the predictive capability of the researchers experiments with the new sequencing data, claiming that not only could they predict the chemicals these fungi were capable of making, but identifying new versions of the same antibiotic chemicals. The reader must infer from the phrasing of this part that the researchers were able to trace the gene and find fungi that were previously unknown to have the ability to produce that particular antibiotic. The implications of information like that open the door wide to not only new means of production, but new variants of chemicals that have otherwise been fighting an uphill battle against antibiotic resistance.

Question:  If it is true that the researchers found antibiotic production previously undiscovered in some fungi, they use the example of the chemical yanuthone, are these inactive genes that must be activated, and how are they accurately and consistently activating these genes to produce this chemical?

Microbes in the News Assignment: Post #2

Article and link: “New HIV reservoir discovered: Findings reveal a second target for cure research’, Science Daily (it should be noted that the article on Science Daily sites the University of North Carolina Health Care as their source and mentions that the original findings were published in Nature Medicine on this same date), April 17, 2017.

 

https://www.sciencedaily.com/releases/2017/04/170417114806.htm

 

Summary: This article describes scientists’ recent discovery that there is another cell within the human body which can act as a reservoir for HIV in addition to T cells: the macrophage. This discovery that macrophages are susceptible to infection by HIV is very important to current research focusing on the treatment of AIDS: this tells researchers that a successful treatment or cure would have to be effective in ridding the virus from both T cells and macrophages. One investigation found that viral replication within macrophages is effectively repressed when antiretroviral therapy is administered; however, the study also found that this effect is only temporary. Following treatment conclusion, macrophages still act as reservoirs for the virus and therefore remain capable of reinfecting the host. More research must be conducted in order to find the most effective way to resolve HIV infection of macrophage cells.

 

Connections: This relates to information we have discussed over the course of the semester in that it discusses a virus, HIV, and also cells involved in the immune response (T cells and macrophages). It also relates to the resolution of disease through treatment and also the ways in which viral cells can find ways to persist inside a host even following treatment; both of these are subjects which were briefly touched on in class this semester.

 

Critical analysis: I found it interesting to learn that HIV can also afflict host macrophage cells in addition to the host’s T cells. It has been known for some time that HIV targets T cells, but I had not heard of any other types of cells being specifically targeted by the virus. I also found it interesting that the antiretroviral therapy typically used in treating HIV infections in T cells does not work effectively on macrophages. I expect that the story is scientifically accurate as I have not seen indications to the contrary. I also did not find anything confusing in the article that would need to be corrected.  I believe that they did a good job in relating this news; it seemed as though they kept their audience in mind, and focused on relating the pertinent details and implications of this discovery without making the article too technical for those who may not have the background to understand a technical explanation.
Question: What are the most significant differences in terms of structure between T cells and macrophages which would cause antiretroviral therapeutic (ART) agents to be effective on T cells but ineffective in macrophages? Which ART’s were tested on the macrophages? What is their mechanism of action? Are scientists already aware of the specific reason that the ART does not work on macrophages?

Microbes in the News Assignment: Post #1

Article and link: “Zika-Fighting Sterile Mosquitoes Released Near Key West’, NBC News, April 19, 2017.

https://www.nbcnews.com/storyline/zika-virus-outbreak/experimental-sterile-mosquitoes-released-near-key-west-n748251

Summary: This article aims to describe the testing of new experimental methods for the reduction of Aedes aegypti mosquito populations, a species which has been previously linked to the spread of multiple diseases, including the Zika virus. The ultimate goal of this testing is to control the spread of the Zika virus through controlling these insect vector populations. One such method has recently been tested in Key West, Florida, where lab-raised male mosquitoes infected with Wolbachia spp. of bacterium were released into habitats known to harbor populations of Aedes aegypti. The lab-raised male mosquitoes will breed with the wild female mosquitoes; however, due to the Wolbachia spp. carried by the male parent, the young produced by this coupling cannot survive to adulthood. While this method involves the use of microbes, there is another technique mentioned which instead involves genetic modification of lab-raised male mosquitoes to obtain a similar result.

Connections: This article related to the material in class through its association with Zika virus, which was covered both in our course material and also in the guest lecture given by Dan Stinchcomb. The use of these microbes by humans to alter a detrimental aspect of an environment is also an example of microbes functioning in environmental bioremediation, another topic covered in class.

Critical analysis: I found this method for mosquito population control extremely interesting. We had learned in class that certain microbes can be used to confer certain health benefits to a host organism through the transfer of particular genes, but I had not yet heard much of this particular strategy involving using members of a population as hosts for the microbe with the aim of stopping the spread of a disease from an insect vector to a human population. Both this method as well as the genetic engineering process mentioned towards the end of the article, if such methods prove effective in their goal and also harmless to the environment, would be extremely useful in inhibiting the spread of the Zika virus and thereby preventing further human infections.

This article was written in such a way as to inform the general public. As such, the scientific details and mechanisms behind the ideas discussed are not mentioned in great detail. In terms of the limited scientific details provided, I believe the article was scientifically accurate, though somewhat vague. The explanation of the science involved was somewhat simplified, and I did not detect any confusing aspects. While I personally feel that they could have included more detail behind the processes mentioned, I can see that the inclusion of too much detail could have been confusing to someone not well-versed in biological concepts. I think the article adequately communicated the highlights of the science to the public, as it stuck to the main ideas and results of the testing in an attempt to be clear and to communicate their ideas effectively.

Question: What is the mechanism by which Wolbachia spp. inhibits the development of the next generation of mosquito? Would the inhibition of mosquito populations through such methods reduce their numbers to the point where other organisms in the food chain might be affected (most specifically those organisms in the food chain which utilize mosquitoes as a food source)? In reference to the genetic engineering method for the control of mosquito population, what is altered or added in the genome of the mosquitoes in order to obtain the desired effect?

A2: Microbes in the News

Article title: Scientists turn food poisoning microbe into powerful cancer fighter

Date: Feb 8, 2017

Author :Michael Price

Source: Science

Link: https://www.sciencemag.org/news/2017/02/scientists-turn-food-poisoning-microbe-powerful-cancer-fighter

 

Assignment author: Morgen Southwood

 

Summary-

Cancer cells are not attacked by our immune system because they are considered to be ‘self.’ There has been some successful research into marking cancer cells for immune system attacks through the use of bacteria. One such treatment for bladder cancer is already approved by the FDA. Bacteria can target cancer cells because they tend to be necrotic and oxygen depleted, which is the kind of weekend tissue pathogens naturally target.     This article focuses on a study on the use of Salmonella. In mouse studies it has been found to eliminate/reduce tumors, and even help prevent secondary tumor formation from human colon cancer metastases injected into mice. The Salmonella used in the studies was altered to produce FlaB which is the protein the spurs the elevated immune responses.

Connection-

This article strongly related to the lectures we are having on immunity. One element of the lectures that is particularly relevant is the way that the immune system has an amplified response the second time it encounters an antigen, and the specificity of antigen identification. From what I understand, this treatment would only deal with tumors that are present as long as the altered Salmonella is present. Since the Immune system is attacking Salmonella, and hasn’t been taught that the cancer cells were the danger all along, this treatment can not cure or prevent future cancers.

Critical analysis-

I really enjoyed the level of detail that this article went into, it described relevant methods and results in a clear and concise manner. I think the terminology used, the explanations provided made this article accessible and informative for the public. What I learned from this article is the targeting mechanism involved in bacterial cancer treatment. I find it very interesting that bacteria can be so relied upon to target the necrotic oxygen depleted cancer cells, and not healthy ones.  One thing I noticed in this treatment is that it has a narrow application. This is not the cure for cancer, it is only one more weapon. I do not this this treatment could be used on an immune compromised person, or on cancers that have morphological of physiological characteristics that cant be targeted by bacteria.

Question-

They have performed an experiment where they injected colon cancer cells into 20 mice. They used the treatment on half of them and observed them for 120 days to see if the cancer remained. In the next experiment they injected metastasizing colon cancer cells into six mice and after 27 days the six treatment mice and 7 control mice were examined for tumors. Briefly, describe what the next experiment on this treatment should entail.

Discovery of an HIV reservoir marker: New avenue toward eliminating the virus

Date: March 15, 2017

Source: CNRS (Délégation Paris Michel-Ange)

Summary:  A protein marker has been discovered that allows cells carrying dormant HIV viruses to be distinguished from healthy cells. This will allow the isolation, and hopefully the destruction of such HIV reservoir cells in order to make remission possible.

Link: https://www.sciencedaily.com/releases/2017/03/170315144033.htm

Connection: We have recently been discussing the reproductive cycles of viruses and how some varieties have the ability to go dormant for periods of time and remain undetected by the host.The dormant viruses inside of reservoir cells may reemerge at any given time.In the case of HIV, the ability of the virus to do so is the reason why patients must receive treatments for the rest of their lives in order to suppress the virus.

Analysis: This article is relatively short, but informative. The writing is easy to follow in layperson terms, but still conveys the discovery effectively. The journal is cited at the bottom of the page, so if one wanted to read the entire discovery in scientific terms, they would be able to. It appears to be scientifically sound, and considering it was published in Nature, that is another mark of its credibility. The fact that something like this has been discovered poses great possibilities in eventually curing HIV, and it was exciting to see this when I was looking up articles.

However, they did have a very small study group, and I hope to see this expanded upon in future studies. Only 12 HIV-positive individuals were checked for the marking protein, and while it was found in all the individuals, I think that for good  science it should have more verified successes before considering it a solidly proven fact.

Question: How long has this research been in progress? It states that the idea of identifying reservoir proteins has been around since 1996, so has this research been in progress for the last 21 years?