Complement Requirement of the Neutralizing Antibody Appearing After Immunization with Smallpox Vaccine

Abstract

A sensitive solid phase radioimmunoassay method was established for the specific quantitative determination of secretory IgA (sIgA) by taking advantage of the dual antigenicities of sIgA, one specific for α‐chain and the other for secretory component (SC). The sIgA and IgA in the sample were first bound by anti‐IgA antibodies coated on the polystyrene tube, then the amount of bound sIgA was quantified by the use of 125I‐labeled anti‐SC antibodies. This method is quite sensitive and allows us to distinguish sIgA from IgA and free SC which usually coexist in exocrine secretions. Linear relationship was observed between the bound radioactivity of radioiodinated anti‐SC and the amount of sIgA in the range of 5 to 60 ng of sIgA. With this method, the urinary sIgA levels in normal children and adults were measured. Urinary sIgA was detected in half of infants within 7 days after birth, while it could be demonstrated in almost all of the infants by 14th day. Then, it gradually increased and reached about a half of the adult level by the age of puberty. This method will be useful for the sensitive and specific measurement of sIgA in various exocrine secretions.

Absence of an All‐or‐None Type of Complement Requirement in Early Neutralizing Antibody against Western Equine Encephalitis Virus

“…In the case of herpes virus, early CRN antibody frequently far exceeds N antibody in level and, as a consequence, enhancement by C' of the neutralizing activity of such a serum is almost of the all-or-none type. A similar fact has been noted with vaccinia [23], bovine parainfluenza [17] and simian her-pes SA 8 viruses [29]. For other viruses, occurrence of a similar response either remains undetermined or is denied [11].…”

“…The present results have indicated that the all-or-none type of C' enhancement of early neutralizing antibody as observed in the case of herpes simplex [9,[40][41][42] and some other viruses [17,23,29] cannot be seen in the immunization of rabbits or guinea pigs with WEE virus. The fact that the 2 species of animals tested exhibited a similar response to the immunization, as well as the failure of the rabbit antiserum to neutralize the closely related Sindbis virus, may deny the possibility that a hitherto unknown virus, which is antigenically closely related to WEE virus, had previously infected the animals and caused a secondary response upon the immunization with WEE virus.…”

“…It is also reported that an artificially produced monovalent 7S antibody to a bacteriophage possesses a lower neutralizing activity than natural bivalent antibody [16]. Whether the above possibility is valid or not must be deter- [23], and so did inoculation of ckickens with Newcastle disease virus [35]. However , these cases may have expressed a secondary response, because the hosts can be supposed to have received previous immunization by vaccination or natural infection , and therefore cannot disprove the above explanation.…”

“…Investigations with rubella [26], Japanese encephalitis [13,24], vaccinia [23], bovine parainfluenza [17], Newcastle disease [21,35], respiratory syncytial [2], certain group B arbo [36,37] and simian herpes SA 8 viruses [29] have revealed occurrence of similar phenomena. However, the data presented have not necessarily coincided as to the extent to which the neutralizing activity of early serum is enhanced by C' as compared with that of late serum.…”

Studies on the Neutralization of Herpes Simplex Virus

“…The effect of C' was especially marked with early serum against relatively large viruses such as herpes [9,31,32], simian herpes [21] or vaccinia [17]. In the case of cytomegalovirus, early and late IgG were equally enhanced by C' [8].…”