Live viral vaccines in a DiGeorge syndrome patient.

We report a case of pneumonia in a 13 month old male child with partial DiGeorge syndrome who died after inadvertently receiving live viral vaccines. Although live viral vaccines have been used safely in some children with DiGeorge syndrome, there are insufficient data to recommend their routine use in those with severe immunodeficiency.

Psoriatic arthritis joint fluids are characterized by CD8 and CD4 T cell clonal expansions appear antigen driven.

The CD8 alphabetaT cell receptor repertoire in joint fluid of individuals with active psoriatic arthritis contained an average of 32 major oligoclonal expansions in many variable genes of the TCR beta chain (BV) families, as shown by beta-chain CDR3 length analysis. Interestingly, a small number of oligoclonal expansions were shared between simultaneous samples of joint fluid and blood; however, most expansions found in joint fluid were not identifiable in blood emphasizing the immunologic specificity of the clonal events for the inflamed joint at a given point of time. The CD4 T cell joint fluid repertoire contained fewer and smaller oligoclonal expansions also largely restricted to the joint, suggesting that CD4 T cells participate perhaps by interacting cognitively to generate the CD8 clones. The inferred amino acid sequence of a single CD8 oligoclonal expansion revealed that they usually are composed of one or a few structurally related clones at the amino acid sequence level with beta-chains that encode identical or highly homologous CDR3 motifs. These were not shared among patients. Moreover, several clones that encoded the same amino acid sequence were found to be structurally distinct at the nucleotide level, strongly implying clonal selection and expansion is operating at the level of specific TCR-peptide interactions. The findings support a model of psoriatic arthritis inflammation involving extensive and selective Ag, likely autoantigen, driven intra-articular CD4, and CD8 T cell clonal expansions.

Myoglobin in the heart tissue of fishes lacking hemoglobin.

Myoglobin has been identified in the heart tissue of three species of antarctic icefish, Chaenocephalus aceratus, Pseudochaenichthys georgianus and Chaenodraco wilsoni. Quantitative analysis shows myoglobin concentrations that are substantially lower than other teleost fish. A simple and accurate method for the direct measurement of myoglobin in tissue is described.