An immune response is a body response to a complex sequence of antigens, to eliminate the antigen. This immune response can involve a wide range of cells and proteins, especially macrophage cells, lymphocytes, complement, and cytokines that interact with each other on a complex basis.
The body’s defense mechanisms consist of nonspecific defense mechanisms and specific defense mechanisms.
A non-specific defense mechanism is also called a nonadaptive or innate component, or natural immunity, meaning a defense mechanism that is not intended for only one type of antigen, but for a wide range of antigen.
Natural immunity has existed since the babies were born and consisted of a wide variety of non-specific elements. So it is not a special defense for certain antigens.
Specific body defense mechanisms or also known as adaptive components or immunity acquired are defense mechanisms aimed specifically at one type of antigen, therefore cannot contribute to other types of antigens.
The difference with the nonspecific body’s defenses is that the specific body defense must be contacted or inflicted in advance by a certain antigen, then it will be formed. While non specific body defenses have existed before it contacts with the antigen.
Immune Response to Extracellular Bacteria
Extracellular bacteria can cause disease through several mechanisms, namely:
Stimulating inflammatory reactions
Stimulating inflammatory reactions that cause tissue destruction at the site of infection. For example, the pyogenic cocci often caused a great suppurative infection.
Production of toxins that produce a variety of effects.
The toxin can be endotoxin and exotoxin.
Endotoxin which is a component of the bacterial wall is a lipopolysaccharide that is a powerful cytokine production stimulator, an adjuvant as well as the polyclonal activator of B lymphocytes.
Most exotoxins have a cytotoxic effect with a mechanism that is not clearly correct. For example, diphtheria toxin inhibits the synthesis of enzymatic proteins and inhibits the elongation factor required for the synthesis of all peptides.
Cholera toxin stimulates the synthesis of AMP cyclic (cAMP) by intestinal epithelium cells that cause the active secretion of chloride, fluid loss as well as severe diarrhea.
Tetanus toxin is a neurotoxin bound to a motor end plate on a neuromuscular junction that causes a very fatal persistent muscle contraction when it is hits respiratory muscles.
Clostridium toxin can cause tissue necrosis that can produce gangrene gas.
The immune response to extracellular bacteria is aimed at elimination of bacteria and neutralization of the toxin effect.
Drugs affecting the immune response
Medications that affect the immune response are used for the treatment of eczema and psoriasis. The use of systemic drugs affecting the immune system is generally under the supervision of a specialist physician in the hospital.
Oral cyclosporine can be used for severe psoriasis and severe eczema.
Methotrexate can be used for severe psoriasis, a dose adjusted according to the severity and measurement of hematology and biochemistry;
The usual dose of methotrexate is 10 to 25 mg once a week, per oral.
Folic acid may be administered to reduce the toxicity of methotrexate that may arise.
For severe psoriasis that cannot be cured with other systemic treatments and photochemotherapy or if other treatments cannot be tolerated, it can be used efalizumab, which inhibits the activation of T-cells and it is indicated for moderate and severe chronic plaques of psoriasis, or etanercept cytokine inhibitors; Etanercept and efalizumab are used for psoriatic arthritis.
Read also: How To Prevent Psoriasis
A topical pimecrolimus is indicated for mild to moderate topical eczema. Short-term use to treat symptoms while prolonged use to prevent relapse.
Topical tacrolimus is indicated in moderate to severe atopic eczema. Both are drugs those uses and safety of long-term use are still evaluated. This medication is usually not the first choice unless there is a specific reason to avoid or reduce the use of topical corticosteroids.
A topical Pimecrolimus is recommended for eczema on the neck and face of children aged 2-16 years, whereas topical tacrolimus is used for moderate to severe atopic eczema in children over 2 years.