The specificity and sensitivity of an indirect and two (an 'ordinary' and a 'rapid') double sandwich enzyme-linked immunosorbent assay (ELISA) procedures for the quantitation of Calloselasma rhodostoma (Malayan pit viper) venom were examined. The three assays were equally sensitive and the accuracy of the assays was not substantially affected by individual variation in the venom composition. The specificity of the assays was examined against 26 venoms from snakes of the families Viperidae and Elapidae. While the double sandwich ELISA procedures were sufficiently specific to be used in the clinical immunodiagnosis of C. rhodostoma bite in Malaysia, the indirect ELISA procedure exhibited extensive cross-reactivity with other Malaysian pit viper venoms. Attempts were made to improve the specificity of the indirect ELISA procedure for the quantitation of C. rhodostoma venom. A 'low ELISA cross-reactivity' venom fraction (termed VF52) was isolated from C. rhodostoma venom by repeated Sephadex G-100 gel filtration chromatography. The indirect ELISA procedure using antibodies to VF52 as immunoreagent showed an improvement in specificity. The use of the indirect ELISA procedure for the detection of C. rhodostoma antibodies was also examined and the results show that the assay was sufficiently specific to be used for retrospective diagnosis of C. rhodostoma bite in Malaysia, in particular when VF52 was used as the coating antigen.
Myeloperoxidase (MPO) is present in azurophilic granules which appear in the promyelocyte stage of differentiation and is expressed in granulomonocytic cells. MPO is usually detected by cytochemistry. The demonstration of peroxidase in at least 3% of bone marrow blasts defines an acute leukaemia as acute myeloblastic leukaemia (AML). MPO is important in distinguishing acute myeloblastic leukaemia (AML) from acute lymphoblastic leukaemia (ALL). It is difficult to diagnose AML with minimal evidence of myeloid differentiation (AML- M0) by conventional light microscopy. However, these AML-M0 blasts can be detected by monoclonal antibodies. Anti-MPO recognizes the enzymatically inactive precursor forms of MPO. There are a few commercially available monoclonal antibodies against MPO. In this study, we evaluated two monoclonal antibodies against MPO from different commercial sources.
1. The hypotensive effect of cross-fostering in spontaneously hypertensive rats (SHR) is thought to involve adjustments in renal function. However, its association with renal anti-oxidant/oxidant balance during cross-fostering is not known. 2. The present study examined the effect of cross-fostering and in-fostering of 1-day-old offspring between SHR and Wistar-Kyoto (WKY) dams on renal anti-oxidant/oxidant status and systolic blood pressure (SBP). Renal anti-oxidant/oxidant status and SBP were determined in the offspring from 4-16 weeks of age. 3. Cross-fostered SHR had significantly lower SBP than in-fostered SHR at 6, 8 and 12 weeks, but not at 16 weeks (127 ± 1 vs 144 ± 2, 138 ± 1 vs 160 ± 1, 174 ± 2 vs 184 ± 2 and 199 ± 2 vs 194 ± 3 mmHg at 6, 8, 12 and 16 weeks, respectively). No differences in SBP were evident between cross-fostered and in-fostered WKY rats. There were no significant differences in levels of thiobarbituric acid-reactive substances (TBARS), protein carbonyl and total anti-oxidant status (TAS) or superoxide dismutase, catalase, glutathione peroxidase (GPx), glutathione S-transferase and glutathione reductase activity between cross-fostered and in-fostered SHR or WKY offspring. However, compared with WKY rats, catalase activity was higher at 6 and 16 weeks, TAS was higher at 16 weeks and GPx activity and TBARS were lower at 16 weeks in SHR. 4. It appears that cross-fostering of SHR offspring to WKY dams during the early postnatal period causes a transient delay in the rise in blood pressure in SHR and that this does not involve the renal anti-oxidant/oxidant system.