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“Some of the protective systems of the human organism as they operate in the body’s defense against disease.
The commentator discusses social and economic tragedies resulting from infectious diseases. As a bacteriologist is shown at work, the commentator says that ultimate victory in the fight against disease requires continued study of the organisms causing disease and of the complicated interplay of defensive mechanisms operating within the body. Accompanying a view of the skin, the commentator states that, as long as this protective coating remains uninjured, bacteria cannot break through easily. The commentator says that the mucous membrane that lines walls of breathing channels and digestive passages is a part of the body’s primary defense. Animation shows a blanket of sticky mucus riding on cilia beneath. An object is carried by ciliary action along the mucous membrane of a frog’s throat. There are views of nasal passages through which mucus passes to the stomach. As a section of the stomach is shown, the commentator explains that the mucous membrane acts as a barrier to bacteria. Accompanying a drawing of the viscera, the commentator states that the mucous lining continues through the intestines and that injury to this delicate membrane may result in local inflammation.
That such inflammation in the region of the appendix may result in appendicitis in human beings is illustrated by contrasting views of normal, inflamed, and ruptured appendixes.
Protective and defensive mechanisms that operate after the skin is punctured are illustrated by drawings of leucocytes leaving capillary walls to move toward bacteria. Microscopic views show the manner in which phagocytes surround and devour the bacteria. A pus-filled abscess forms as blood fluids leak through the vessel wall and support the walling-off action of the phagocytes.
By drawings of the lymphatic passages, the beginnings of the second line of defense are shown. Bacteria from a nail wound enter lymphatic passages and are carried in the lymph to filtering bodies called lymph nodes. Within these are mazelike passages lined with phagocytic cells. The following scenes show the distribution of these nodes in various parts of the body.
The third line of defense is introduced by a drawing of the circulatory system. There follow views of bacteria passing through the circulatory system, finally reaching the liver and the spleen. Here they are engulfed as they run the gantlet of devouring kupffer cells.
A title states that during all these processes the body tissues have been stimulated to produce invisible chemical substances called “antibodies” which enhance the capacity of the body to resist further attacks by bacteria of the same kind. There follow scenes that demonstrate the action of serum upon typhoid bacteria as it causes them to agglutinate, thus facilitating phagocytosis. This same process is demonstrated with the use of cholera germs. Vaccination, by which antibody production is artificially induced, and antitoxin injection, by which antibodies are injected into the blood stream, are demonstrated.”
Public domain film from the Prelinger Archive, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied.
The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).
The immune system is a system of biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, from viruses to parasitic worms, and distinguish them from the organism’s own healthy tissue.
Pathogens can rapidly evolve and adapt, and thereby avoid detection and neutralization by the immune system, however, multiple defense mechanisms have also evolved to recognize and neutralize pathogens…. These mechanisms include phagocytosis, antimicrobial peptides called defensins, and the complement system. Jawed vertebrates, including humans, have even more sophisticated defense mechanisms, including the ability to adapt over time to recognize specific pathogens more efficiently…
Disorders of the immune system can result in autoimmune diseases, inflammatory diseases and cancer. Immunodeficiency occurs when the immune system is less active than normal… In contrast, autoimmunity results from a hyperactive immune system attacking normal tissues as if they were foreign organisms. Common autoimmune diseases include Hashimoto’s thyroiditis, rheumatoid arthritis, diabetes mellitus type 1, and systemic lupus erythematosus. Immunology covers the study of all aspects of the immune system…
