Biomedical subjects

A E Larsen

Publications and source records attributed to A E Larsen.

41 records · Page 3Linked to original sources

PubMed1969

The pathogenesis of Aleutian disease of mink. I. In vivo viral replication and the host antibody response to viral antigen.

Mink inoculated with 1 x 10(5)ID(50) of Aleutian disease virus revealed very high virus titers in the tissues 8-18 days later. The highest virus titers observed were 5 x 10(8)ID(50) per g of spleen and 1 x 10(9)ID(50) per g of liver 10 days after inoculation. Concomitant with the increase in infectious virus titers, viral antigen(s) was found in the cytoplasm of macrophages in the spleen and lymph nodes and in Kupffer cells in the liver. Antiviral antibody was assayed by indirect immunofluorescence, using sections of infected liver as the source of antigen. A few mink infected for 9 days and all those infected 10 days or more developed antibody to Aleutian disease virus antigen(s). By 60 days after infection, when hypergammaglobulinemia was marked, the mink had an exceptionally high mean antibody titer of 100,000. The pathogenesis of the glomerulonephritis of Aleutian disease is apparently related to formation of viral antigen-antibody-complement complexes which lodge in glomerular capillaries. No evidence was found that viral infection of the kidney took place, and no autoimmune responses were found. In this "slow-virus" disease the virus replicates rapidly and the morphologic and biochemical manifestations of disease are apparently due to the continuing interplay between a replicating antigen and the host immune response.

Animals↗

PubMedDate not supplied

Time-dependent disappearance of ochratoxin A residues in tissues of bacon pigs.

Crystalline ochratoxin A was administered to bacon pigs for one month. After termination of toxin exposure the pigs were slaughtered at different intervals and analyses for ochratoxin A residues in four tissues were conducted. Kidneys contained the highest concentrations, and fat the lowest, at each interval. Ochratoxin A disappeared from muscles and fat after 2 weeks, from liver after 3 weeks, and from the kidneys after 4 weeks. The toxin disappeared from tissues exponentially. All the pigs would have passed the meat inspection because no pathologic lesions were developed although tissues contained mycotoxin residues. The results of this study indicate that contamination of meat by ochratoxin A may be avoided by feeding pigs ochratoxin-free feed during the last 4 weeks before slaughter.

Animals↗

PubMedDate not supplied

False positive and false negative reactions in HLA B-27 antigen testing.

The recent commercial availability of HLA B-27 antiserum now enables laboratories without prior experience in HLA typing to test for this antigen. False positive and false negative reactions frequently occur and require judicious interpretation. In our laboratory, 30 of 100 specimens were positive for B-27 and 70 were negative. Of the 30 positive, 10 (33%) failed to react against every antiserum tested. Twenty-nine of the 70 negative specimens (41%) reacted falsely with one or more B-27 antisera. A significant cause of false positive reactions was cross-reaction of the B-7 antigen with B-27 antisera (13 of 15 B-7 positive, B-27 negative specimens). For valid B-27 testing, use of more than one B-27 antiserum is included.

False Negative Reactions↗

PubMedDate not supplied

Selection of compatible kidney donors for recipients with multiple cytotoxic antibodies.

Cytoxic antibodies developed in 33 (14.6%) of 226 renal transplant candidates while awaiting transplantation. Antibody formation was not associated with primary kidney disease, nor was the frequency of antibody formation increased following deliberate transfusion. Analysis of the HLA types of panel cells against which cytotoxic sera failed to react predicted donor kidney antigens which would be acceptable to the recipient. Crossmatching with all stored, reactive serum samples as well as a current sample, is imperative.

Antibody Formation↗

PubMedDate not supplied

A summary of the results of screening for HLA antibodies for one year.

In one year, 748 serum specimens from obstetric patients were screened for HLA antibodies. Of the 284 showing antibody activity, 179 were nonspecific and 68 were multispecific. Thirty-seven (5%) were found to be monospecific, representing 11 specificities, of which the most common were anti-B7, -B8, -A2, and -B12. Recovery of antisera for reagent use was financially feasible.

Antibody Specificity↗