Role of Immune Response in Stress and PTSD

The assignment content discusses the role of stress and immune response, with a focus on post-traumatic stress disorder (PTSD). It explores the relationship between stress, immune modulators, and the brain, highlighting the importance of cortisol in PTSD. The content also touches on the technology available today that could facilitate testing, including brain imaging, blood chemistry tests, and DNA mapping.

STRESS AND THE IMMUNE RESPONSE
1. Observation and generalization
The first part i.e., introduction of assignment addresses the generalized background of the
topic. It states that about the role and regulation of immune cells under normal conditions.
The antigen or pathogen if any enters into body is going to be destroyed via inflammatory
mediators. The consequences could be vasodilatation and enhancing the vascular
permeability leading to an increase the blood flow at the injured region to mitigate the
adverse reactions by phagocytosis. Examples are cited to show the immune response. Most
content is related to the immune responses rather stress.
2. Formulation of hypothesis
The hypothesis behind in the said topic is shown as a part in posttraumatic stress disorder
(PTSD) and the complement system and remaining part in ‘inflammatory response and the
brain’. However the hypothesis is not clearly demonstrated in the respective sections. A
marginal description is provided in the sections based on available information. The
evidences comprise of an increase in the activity of complement pathway, immune
modulators (IL-1b, Il-6) and involvement of alternative pathways leading to signaling the
phagocytosis stimulation and other immunization reaction. The assumptions of stress is
related to the alterations of these pathway can contribute for the diseases (schizophrenia,
Alzheimer’s diseases, Hovhannisyan, 2010). Another assumption is that there exists an
interconnection between immune system and inflammation processes. The utilization of
energy for immune response made the individual to reduce their behavior leading to
disruption of hippocampus activity. In addition, the adaptation of defense against the
pathogens increases the activity of CNS for the redirection of the organism’s resources. These
are the hypotheses behind the immune response
3. Did your hypothesis contain information that can be accepted as the absolute truth?
If not, what information was missing? (HINT: Think back to the studies about cortisol
and PTSD.) Based on the information that was missing from your hypothesis, what
could you test in order to obtain more information on the unknown piece?
No, the hypothesis pertaining to the details have to be improved substantially. The details are
superficially provided and a deep emphasis should have been provided. For instance, the role
of stress contributing hormones and their influence by immune modulators is missing. The
stress is thought to contribute to both initiation and relapse with the use or presence of
external modulators (Ranabir & Reetu, 2011), certain neuronal and hormonal responses. The
hormone, cortisol is thought to release and increase from the pituitary-adrenal axis due to
stress. The chronic dysregulation of the hormone could cause a functional impairment leading
to the development of ‘psychologically traumatized’ and post-traumatic stress disorder
(PTSD) (Sherin & Nemeroff, 2011). The neuroendocrine hormones of the hypothalamic-
pituitary-adrenal (HPA) axis influence the expression of PTSD. One of the essential
hormones that contribute for the cause of PTSD is cortisol (Van Voorhees et al., 2014). The
neuroinflammation because of inflammatory process releases the neuropeptides such as
substance P or other inflammatory mediators leading to activation of mast cells. The insight
of another hypothesis is based on stressful situations that induce corticosterone secretion that
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in turn reduces the immune reactions via diverse mechanisms (Stier et al., 2009). Both the
sections of the assignment describes with varying modes of assumptions. Instead the
preceding details have to be covered in hypothesis.
4. Do a bit of research on the technology available today that could facilitate this test.
Examples of new technology include brain imaging, blood chemistry and hormone level
tests, CAT scans, MRIs, and DNA mapping. What step of the scientific method does this
require?
Yes, the available methods can be utilized for the characterization and assessment of
contributing factors for the stress and PTSD. Quantitative method is available for the
estimation of cortisol and is based on the liquid chromatography tandem mass spectrometric
assays (LC-MS/MS) (Turpeinen & Hamalainen, 2013). The PTSD can be diagnosed by a
recurrent and intrusive distress of recollections of the event including images utilizing
computerized tomography or magnetic resonance imaging. In addition, the psychology of
individual has to be evaluated. The psychological parameters pertaining to the behavior,
cognitive skills and perceptions should be determined. The assessment can be done by a step-
by-step method and comprises of identification of signs and symptoms of patient, estimation
of blood chemistry for the identification of contributing factors utilizing immunoassay
method and chromatographic methods. Stastical methods such as design of experiments can
be implemented to perform the experiments in the cause identification. Control experiments
can be included to avoid bias and compare the test under consideration for significance.
5. Now that you have some additional information, briefly and in simple terms, describe
how you would test the missing information and which step of the scientific method this
accomplishes
A systematic procedure is missing in the case therefore, can be implemented for the testing
and implementation of scientific method. First, the suspected individual can be subjected for
psychological evaluation. The biological samples so collected from the individual can be
subjected for the assessment of immune modulators, antigens and pathogenic substances. The
biological samples can be tested for microbiological testing. The chemistry of blood and
serum for hormones such as cortisol can be determined utilizing chromatographic methods.
The radiological images of brain and nervous system can be made using CT scan and MRI
scans to identify the defects in the central nervous system. The link in the case provided is
missing pertaining to the interpretation of immune modulators and damage of brain tissue.
Therefore, the data has to be interpreted with the causes identified from chemical evaluation
and images of brain and nervous system. The advanced brain imaging techniques can help in
differentiating the post-traumatic stress disorder (PTSD) from those with mild traumatic brain
injury (MTBI). A typical image of patient with PTSD disorder is shown in Fig-1. In case of
difficulty in identification of disease, hybrid imaging with positron emission tomography and
computed tomography (PET/CT) can be used. The advanced methods can be used to
characterize the pituitary region of the brain to distinguish the two conditions.
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Fig-1: A typical image that differentiate the PTSD and mild brain injury
References
HovhannisyanLP., et al. (2010). Alterations in the complement cascade in post-traumatic
stress disorder. Allergy Asthma ClinImmunol, 6(1), 3.
Ranabir, S., & Reetu, K. (2011). Stress and hormones. Indian Journal of Endocrinology and
Metabolism, 15(1), 18–22. http://doi.org/10.4103/2230-8210.77573
Sherin, J. E., & Nemeroff, C. B. (2011). Post-traumatic stress disorder: the neurobiological
impact of psychological trauma. Dialogues in Clinical Neuroscience, 13(3), 263–278.
Stier, K.S., Almasi, B., Gasparini, J., Piault, R., Roulin, A & Jenni, L (2009) Effects of
corticosterone on innate and humoral immune functions and oxidative stress in barn
owl nestlings. J Exp Biol. 212(13), 2085-91. doi: 10.1242/jeb.024406.
Turpeinen, U & Hamalainen, E (2013) Determination of cortisol in serum, saliva and urine.
Best Pract Res Clin Endocrinol Metab. 27(6), 795-801. doi:
10.1016/j.beem.2013.10.008. Epub 2013 Oct 25.
Van Voorhees, E. E., Dennis, M. F., Calhoun, P. S., & Beckham, J. C. (2014). Association of
DHEA, DHEAS, and cortisol with childhood trauma exposure and posttraumatic
stress disorder. International Clinical Psychopharmacology,29(1), 56–62.
http://doi.org/10.1097/YIC.0b013e328364ecd1
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