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When used simultaneously, latex proteins Hev b 2 and Hev b 7 reacted significantly with specific serum IgE in 80% of health care workers and 92% of spina bifida patients with latex allergy by ELISA technique, while this combination gave lower positivity when the RASTs were used. By the addition of Hev b 3, specific IgE was detected in all spina bifida patients with latex allergy. Both RASTs failed to show specific IgE in the control subjects, while the ELISA showed significant latex-specific IgE in 22% of controls.

A novel actin binding protein has been isolated from chicken gizzard muscle. When isolated, a pair of proteins with apparent molecular weights of 79 kDa and 103 kDa are obtained; both proteins have a pI near 9.3. Peptide mapping indicates that these proteins are related. Antibodies against this protein cross-reacted with proteins from other smooth muscle containing tissues as well as skeletal and heart muscle. Traces of cross-reactive material were also detected in brain and kidney tissue. The affinity of this protein for actin is ca. 1x10(6) M(-1). Interestingly, this actin binding protein is a potent actin-bundling agent. A partial sequence analysis confirmed that there were no previously reported homologues in smooth muscle. However, considerable homology was found with the protein synaptopodin that is found in nervous tissue and kidney but is absent from muscle tissue. It is likely that the new protein is a member of the synaptopodin family. We call the smooth muscle actin binding protein fesselin.

The 2 major allergenic proteins in vespid venoms are antigen 5s and phospholipases (PLs). Vespid PLs have a molecular weight of about 34,000 and have been previously shown to have an A₁B specificity, unlike the A₂ specificity of bee PLs. The complete amino acid sequences of the venom PL from the yellow jacket, Vespula maculifrons, and the more acidic isoenzyme from the white faced hornet, Dolichovespula maculata, have been determined by sequencing overlapping peptides isolated from enzyme and chemical digests of the proteins. Ves m 1 is composed of 300 amino acids, with variants found at 3 positions. Dol m 1.02 is composed of 303 amino acids with variants at 2 positions. Comparison with the sequence of Dol m 1.01 determined by cDNA sequencing gave 66.7% identity with Dol m 1.01 with almost all variation in the first 131 positions. Ves m 1 showed 69% identity with Dol m 1.01 and 38.7% with Dol m 1.02. Comparison of the PL sequences with the Protein Identification Resource data base showed many similarities with the lipase family, but very little relationship to known PLs. The amount of structural similarity between Dol m 1 and Ves m 1 is similar to that found among antigen 5 molecules of different genera, and is sufficient to account for antigenic cross-reactivity. There appear to be a number of highly conserved regions of the PL molecules, especially in the C-terminal 168 residues. These regions may from common epitopes found in several species and genera of vespids. Antibodies against these common epitopes will not be able to distinguish among PLs from various vespids. The finding of 2 significantly different sequences for Dol m 1 is parallel to the finding for Dol m 5.

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