Maternal antibody

Where HIV antibody testing suffice for adults in children les than 18 months of age, a positive HIV antibody test is not sufficient to confirm an HIV diagnosis since maternal antibodies cross the placenta... 

Rodent species (i.e., rat or mouse) are cheaper and easier to house and handle than rabbits, particularly for the required postnatal examinations. The use of a rodent species must be justified by demonstrating an adequate exposure of the fetus to the induced maternal antibodies. The rabbit generally shows a greater degree of maternal immunoglobulin transport across the placenta (8) and therefore is often the preferred species (Fig. 1). 

Once or twice before mating, as necessary to induce a peak in maternal antibody titers during pregnancy (see Note 3). 

A preliminary study is often necessary to select the appropriate species for the main study, based on a species comparison of the pre- and postnatal transmission of the maternal antibodies to the offspring. A typical study design may be as follows ... 

In developing countries, measles can be a very severe disease, with mortality rates as high as 10 percent. Hence, vaccination is recommended for all children at the earliest possible age. Currently, the WHO recommended nine months as the age for measles vaccination, taking into account maternal antibody levels and vaccine intake, as well as disease incidence. 

The innate system is of special importance during early infancy. Prior to birth and for at least 4-12 months after birth a child s immune system is poorly developed. It may not become fully competent until age 5.34 35 During the prenatal period maternal antibodies are transferred to the child. IgG crosses the placenta and enters the fetal circulation. Breast milk provides IgA, which remains largely in the child s gut, as well as other protective proteins. UNICEF and the World Health Organization recommend breast-feeding to two years or beyond 34... 

Neonatal lupus is caused by cross-reaction between maternal antibodies and fetal tissue. It is particularly interesting because it provides a unique opportunity for studying the pathogenic role of autoantibodies. 

Although an association between maternal connective tissue disease and cardiac involvement in neonatal lupus was suspected as early as 1901 (M22), the association between skin disease in an infant and maternal autoimmune disease was not reported until more than 50 years later. McCuistion and Schoch (M13) described an infant with a scaly erythematosus rash whose mother had systemic lupus erythematosus. The typical association of maternal antibodies to Ro/SSA was described for congenital heart block (CHB) several decades later in 1983 (R5, S8). 

Coe CL, Lubach GR, Izard KM. Progressive improvement in the transfer of maternal antibody across the order primates. Am J Primatol 1994 32 51-5. 

Sabin, A. B., Flores Arechiga, A., Fernandez de Castro, J., Albrecht, P., Sever, J. L., and Shekarchi, I. (1984), Successful immunization of infants with and without maternal antibody by aerosolized measles vaccine. II. Vaccine comparisons and evidence for multiple antibody response, JAMA, 251, 2363-2371. 

PlPlAl-negative platelets are used to treat neonatal alloimmune thrombocytopenic purpura, a rare, transient, but severe thrombocytopenia in the newborn due to platelet destruction by maternal antibody (1). The mother is usually a PlPlAl-negative person who has produced anti-PIPIAI as a result of previous blood transfusions or pregnancy. The antibody crosses the placenta and destroys the PIPIAI-positive platelets of the neonate. 

Maternally acquired antibodies will react not only with antigen associated with a threatening infection but also with antigens introduced to the body as part of an immunization programme. Premature immunization, i.e. before degradation and elimination of the maternal antibodies, will therefore reduce the potency of an administered vaccine. This aspect of the timing of a course of vaccinations is discussed later. 

Vaccination against viruses, such as influenza and measles, commonly involves parenteral (subcutaneous or intramuscular) administration of a live, attenuated virus or a killed virus. The inhalation route is being examined as a means of immunizing patients because it circumvents logistical problems associated with parenteral administration, such as needle sterility issues, patient aversion to needles, and the need for administration by a health care professional. In very young children, maternally derived IgG antibodies may prevent successful immunization [118]. The inhalation route may allow vaccination of these children because the immunological response of the airways is less likely to be influenced by maternal antibodies [118], Aerosol immunization has been shown to be effective against measles [119] and, in some respects, is more efficacious than parenteral immunization [120],... 

In the newborn infant, resistance to infectious agents is first achieved by maternal antibodies that cross the placenta during fetal development or antibodies from mammary gland secretions transferred to a nursing infant. Subsequent antibody-mediated protection is provided by antibodies synthesized by the B cells of the individual as described above. Following this natural sequence, the focus on molecules and how molecular structures account for biological function begins with antibody structure. 

The age of the recipient is another important determining factor in vaccine and toxoid response. In the first few months of life, maternal antibodies acquired via transplacental transfer during the third trimester of gestation protect an infant. However, the maternal antibody also inhibits the immune response to live vaccines because the circulating antibodies neutralize the vaccine before the infant has the opportunity to mount an immune response. For this reason, live vaccines are not administered until maternal antibody has waned, generally by age 12 months. ... 

The measles vaccine is administered subcutaneously as a0.5-mL dose in the arm (or in the thigh if the patient is younger than 15 months of age). The vaccine is administered routinely for primary immunization to persons 12 to 15 months of age, usually as the MMR vaccine. The measles vaccine is not administered earlier than 12 months (except in certain outbreak circumstances) because persisting maternal antibody that was acquired transplacentally late in gestation can neutralize the vaccine virus before the vaccinated person can mount an immune response. A second dose of MMR is recommended when... 

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