Spinal muscular atrophy (SMA) and Lymph Nodes

A lymph node is a small ball or an oval-shaped organ of the immune system, distributed widely throughout the body including the armpit and stomach/gut and linked by lymphatic vessels. Lymph nodes are garrisons of B, T and other immune cells. Lymph nodes act as filters or traps for foreign particles and are important in the proper functioning of the immune system. They are packed tightly with the white blood cells called lymphocytes and macrophages.
Lymph nodes also have clinical significance. They become inflamed or enlarged in various conditions, which may range from trivial, such as a throat infection, to life-threatening such as cancers. In the latter, the condition of lymph nodes is so significant that it is used for cancer staging, which decides the treatment to be employed, and for determining the prognosis.
Lymph nodes can also be diagnosed by biopsy whenever they are inflamed. Certain diseases affect lymph nodes with characteristic consistency and location.
The lymph fluid inside of the lymph nodes contains lymphocytes, a type of white blood cell, which are continuously recirculated through the lymph nodes and the bloodstream. Molecules found on bacteria cell walls or chemical substances secreted from bacteria, called antigens, may be taken up by dedicated antigen presenting cells such as dendritic cells into the lymph system and then into lymph nodes. In response to the antigens, the lymphocytes in the lymph node make an antibody which will go out of the lymph node into circulation, seek, and target the pathogen producing the antigen by targeting it for destruction by other cells and complement. Other immune system cells will be made to fight the infection and “sent” to the lymph nodes. The increased numbers of immune system cells fighting the infection will make the node expand and become “swollen.”

The anterior horn of the spinal cord (also called the anterior cornu, anterior column or ventral horn) is the ventral (front) grey matter section of the spinal cord. The anterior horn contains motor neurons that affect the axial muscles while the posterior horn receives information regarding touch and sensation. The anterior horn is where the cell bodies of alpha motor neurons are located.

Spinal muscular atrophy (SMA) is an incurable autosomal recessive disease caused by a genetic defect in the SMN1 gene which codes SMN, a protein necessary for survival of motor neurons, and resulting in death of neuronal cells in the anterior horn of spinal cord and subsequent system-wide muscle wasting (atrophy).
Spinal muscular atrophy manifests in various degrees of severity which all have in common general muscle wasting and mobility impairment. Other body systems may be affected as well, particularly in early-onset forms. Spinal muscular atrophy is the most common genetic cause of infant death.

Monday, Apr 30, 2012
YourHealth, AsiaOne

What do you do when your 6-month-year-old daughter is diagnosed within incurable genetic disease, and will very likely not live long beyond her second birthday?
For Mike and Laura Canahuati, they chose to write a blog in her name – detailing their daily joys and trials with her, accompanied with a ‘bucket list’ of things to accomplish before her death.
Baby Avery was diagnosed with Spinal Muscular Atrophy (SMA) Type 1 on a Good Friday, June 4, 2012.

This means that little Avery, who has already lost her ability to move her legs, will eventually lose the ability to move her arms and her head.
When this happens, it will become increasingly difficult, and in the end impossible, for her body to pump air through her lungs.
This is why most babies diagnosed with SMA Type 1 have a life expectancy of less than two years of age.
There is even the possibility of dying a few months or even weeks after birth. Even with the help of a respirator, life expectancy can only be stretched till ten years of age.
One in 6,000 babies is born with one of the four types of SMA, with Type Zero the worst. However, that usually occurs with fetuses, the couple said.
Much of the blog, written in the first person in Avery’s voice, is the work of the father, Mike.
He writes: “My mommy, daddy, and grandparents have chosen to help me fight this disease, while embracing this news and helping me chronicle my “bucket list” experiences through this blog.
“So at this point, my family & friends can either sit back and watch me die and let my life be about doctors visits and tear filled days, or everyone can embrace what my future holds and we can make each day I’m here a memorable one…starting now.”
Light-hearted and humorous, the blog and the bucket list is written as though Avery will live far beyond her estimated life expectancy and experience life’s milestones.
In her wish-list, ‘Avery’ writes her hopes of ‘attending a sleep over’, ‘going hiking’, to ‘play dress up in my mommy’s closet and have a photo shoot’ and ‘celebrate my real 1st birthday’.
Others include:

  • Lose my first tooth and get a present from the tooth fairy
  • Meet Santa Claus
  • Dress up for Halloween and go trick or treating
  • Get a tattoo
  • Have a father daughter dance while watching Father of The Bride

You need to study the molecular structure level to understand how to engineer new cells that can replace those that has been affected by the disease. – Contributed by Oogle.