Cells with a low density of parasite-specific antigens on their surface are postulated to be susceptible to a cell-mediated attack but not to effector mechanisms normally activated following the binding of specific antibody to the infected cell. It is further postulated that such infected cells normally induce a cell-mediated response, and that cells infected with slow-growing intracellular parasites have a low density of parasite-specific antigens on their surface. Despite these general postulates, cell-mediated immunity is not invariably induced following natural infection by certain slow-growing parasites, such as those responsible for leprosy, tuberculosis, and the leishmaniases, and antibody can be induced that is exclusive of a strong, cell-mediated response. It is proposed that certain events in such cases subvert the normal regulatory processes that control the class of immunity induced. In these cases, the parasite-infected cells, bearing a low representation of parasite antigens, induce antibody even though they are not susceptible to antibody-dependent effector mechanisms, and so they are not eliminated. In this case, chronic infection and uncontrolled growth of the parasite occurs, often with fatal consequences.
BT - Immunology and cell biology C1 - http://www.ncbi.nlm.nih.gov/pubmed/1478700?dopt=Abstract DA - 1992 Oct DO - 10.1038/icb.1992.44 J2 - Immunol. Cell Biol. LA - eng N2 -Cells with a low density of parasite-specific antigens on their surface are postulated to be susceptible to a cell-mediated attack but not to effector mechanisms normally activated following the binding of specific antibody to the infected cell. It is further postulated that such infected cells normally induce a cell-mediated response, and that cells infected with slow-growing intracellular parasites have a low density of parasite-specific antigens on their surface. Despite these general postulates, cell-mediated immunity is not invariably induced following natural infection by certain slow-growing parasites, such as those responsible for leprosy, tuberculosis, and the leishmaniases, and antibody can be induced that is exclusive of a strong, cell-mediated response. It is proposed that certain events in such cases subvert the normal regulatory processes that control the class of immunity induced. In these cases, the parasite-infected cells, bearing a low representation of parasite antigens, induce antibody even though they are not susceptible to antibody-dependent effector mechanisms, and so they are not eliminated. In this case, chronic infection and uncontrolled growth of the parasite occurs, often with fatal consequences.
PY - 1992 SP - 343 EP - 51 T2 - Immunology and cell biology TI - An hypothesis to explain why cell-mediated immunity alone can contain infections by certain intracellular parasites and how immune class regulation of the response against such parasites can be subverted. VL - 70 ( Pt 5) SN - 0818-9641 ER -