Antibodies humoral immune response

IL-2 acts as a critical autocrine growth factor for T-cells, and the magnitude of the T-cell response is largely dependent upon the level of IL-2 produced. IL-2 also serves as a growth factor for activated B-lymphocytes. In addition to promoting proliferation of these cells, IL-2 (as well as some other interleukins) stimulates enhanced antibody production and secretion. In this way, it effectively potentates the humoral immune response. 

TABLE 15.5. Antibodies Involved in the Humoral Immune Response... 

As described previously, the humoral immune response results in the proliferation, activation, and subsequent production of antibodies by B cells following antigenic exposure and stimulation. The functionality and interplay between the three primary types of immune cells (macrophage, B cells, and T cells) required to elicit a humoral response can be assessed through various in vitro assays using cells from the peripheral blood or lymphoid tissues. 

MUCl peptide was able to trigger a humoral immune response generating speeifie antiMUCl antibodies (34). 

Antibody a protein produced by plasma cells as part of the humoral immune response that has the ability to recognize and bind to the antigen that elicited it. 

In addition, a distinction is made between cellular and humoral immune responses. The T lymphocytes (T cells) are responsible for cellular immunity. They are named after the thymus, in which the decisive steps in their differentiation take place. Depending on their function, another distinction is made between cytotoxic T cells (green) and helper T cells (blue). Humoral immunity is based on the activity of the B lymphocytes (B cells, light brown), which mature in the bone marrow. After activation by T cells, B cells are able to release soluble forms of their specific antigen receptors, known as antibodies (see p. 300), into the blood plasma. The immune system s memory is represented by memory cells. These are particularly long-lived cells that can arise from any of the lymphocyte types described. 

Humoral Immune Response in Chronic Inflammatory Processes. The specificity of the diagnostically relevant intrathecal antibodies depends on the underlying cause of the disorder. In the case of chronic infective processes, the antibodies are exclusively targeted against the causative organism (F5). Increased IgC levels are found in about 30% of patients with chronic meningitis or encephalitis from various causes, such as bacteria, virus and protozoa, and in diseases like polyradiculitis, sarcoidosis, and chronic myelopathy (LI). 

To initiate a T-cell immune response, antigen presenting cells have to display antigenic peptides com-plexed with the major histocompatibility complex (MHC) on their cell surface. The T-cell receptor of CDS cells is specific for the peptide-MHC class I complex while the CD4 cell receptor binds the peptide-MHC class II complex. This binding of the peptide-MHC II complex stimulates CD4 cell proliferation and subsequent lymphokine release. This CD4 cell response can initiate a delayed hypersensitivity reaction. However CD4 activation and the production of various lymphokines is also needed for the generation of cytotoxic T-cells and for the differentiation of plasma cells from B-lymphocytes and the antibody response by these plasma cells. For their role in also the humoral immune response CD4 cells are called T-helper cells. 

Mechanism of Action Antibodies of multiple specificities interact with lymphocyte surface antigens, depleting numbers of circulating, thymus-dependent lymphocytes and interfering with cell-mediated and humoral immune responses... 

The proteins at the heart of the humoral immune response are soluble proteins called antibodies or immunoglobulins, often abbreviated Ig. Immunoglobulins bind bacteria, viruses, or large molecules identified as foreign and target them for destruction. Making up 20% of blood protein, the immunoglobulins are produced by B lymphocytes, or B cells, so named because they complete their development in the feone marrow. 

There are also cells that appear as 10 pm circles with large round nuclei and a narrow rim of cytoplasm these are the lymphocytes, present in a concentration of about 2 x 106 per cm3. Lymphocytes (including both B lymphocytes and T lymphocytes) are responsible for a great variety of the functions that are known as cellular and antibody (humoral) immunity, as well as for the regulation of those functions. The third (and most frequent) group of leukocytes occurs... 

Acquired immunity is immunity that develops with exposme to antigens the immune system builds a defence that is specific to that antigen. B-ceU lymphocytes, produced in the stem cells of the bone marrow, synthesise and release antibody they oversee the humoral immune response. T-ceU lymphocytes, produced in the bone marrow but sensitised in the thymus, are the basis of the ceU-mediated immune response. 

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