Serologic dissection of HLA-D specificities by the use of monoclonal antibodies

To study the gene products of the HLA complex, we produced two monoclonal antibodies, termed HU-18 and HU-23. They were active in complement-dependent cytotoxicity and detected B-cell alloantigens encoded by a locus (or loci) linked to HLA. When three types of HLA-DR4 homozygous B-cell lines with different HLA-D specificities were tested for reactivity with HU-18 and HU-23, they displayed distinct reaction patterns depending on the HLA-D specificities they possessed: EBV-Wa (HLA-DYT homozygous), negative for both HU-18 and HU-23; KT2 and KOB (HLA-DKT2 homozygous), positive only for HU-18; and ER (HLA-Dw4 homozygous), positive for both. These differential reaction patterns were further confirmed by testing against a panel of 17 HLA-DR4-positive peripheral blood lymphocytes with known HLA-D specificities. Thus, these monoclonal antibodies allow us to identify HLA-DYT, HLA-DKT2, and HLA-Dw4 solely by serologic methods. This is the first clearcut serologic identification of these three HLA-DR4-associated HLA-D specificities, which have been indistinguishable by conventional serology and identified only by cellular techniques. It is hoped that immunochemical investigations using HU-18 and HU-23 will advance our understanding of the HLA-D region on a molecular level.     

The D-JH complex is an intermediate to the complete immunoglobulin heavy-chain V-region gene

We have examined the organization of the immunoglobulin JH segments in three clones derived from a single Abelson murine leukemia virus-transformed cell. Cloning and nucleotide sequence analyses of the JH-containing fragments have revealed the rearrangement from the preformed D-JH complex to the complete VH-D-JH gene, which was accompanied by the expression of the intra-cytoplasmic mu chain. In one case a JH segment downstream to the preformed D-JH was used to create a new VH-D-JH gene. Upon the D-JH and VH-D-JH rearrangements the intervening D segments were deleted from the chromosome. One of the expressed VH genes suffered from a large deletion of the 3' portion (including the 95th cysteine residue) of the VH segment. We discuss the possible mechanism of the allelic exclusion.     

COMPARISON OF THE FATTY ACIDS OF LIPIDS OF SUBCELLULAR BRAIN FRACTIONS

Abstract— Rat brain grey and white matter were fractionated to yield myelin, nerve terminal, synaptic vesicle, nerve terminal 'ghost', and microsomal fractions of white and grey matter. Ester-type glycolipids were found in all fractions except myelin, while cerebrosides occurred in significant concentrations only in myelin and white microsomes. Comparison of the fatty acid profile of the ethanolamine- and serine-containing phospholipids showed marked differences between myelin and the particles from grey matter, while the microsomes of white matter were of intermediate composition. Docosahexaenoic acid, a minor acid in myelin, was a major fatty acid in microsomes of grey and white matter. The fatty acid composition of sphingomyelin was distinctly different in the fractions derived from grey and white matter, clustering about stearate and nervonate in the latter, but only about stearate in the grey. Marked differences in the positional distribution of fatty acids were seen within phosphatidyl choline from myelin and nerve terminals. Ribonucleic acid was found in nerve terminal and synaptic vesicle fractions. The sphingosine found in the ganglioside from microsomes of both grey and white matter was similar with respect to distribution of the C₁₈ and C₂₀ homologues.
The possibility is discussed that microsomes furnish characteristic lipids for the synthesis or renewal of specific membranes, and that these lipids are accumulated somewhat before being released.     

The brachial plexus of a capuchin monkey (Cebus capucinus)

Brachial plexuses of an adult female capuchin monkey (Cebus capucinus) were observed macroscopically. The main characteristic features of the organization of the plexus were as follows:Substantially the same organization was observed in the plexuses on both sides. The plexuses were formed by the union of the 5th–8th cervical nerves and the 1st thoracic nerve. The component from C5 contributed only to the superior posterior division; consequently the superior trunk in the strict sense was lacking. The medial cord was a peripheral extension of the inferior anterior division and formed a common trunk with the lateral root of the median nerve. Therefore, the medial root of the median nerve in the strict sense was absent, and the median nerve arose from the common trunk with the ulnar nerve. In the plexus on the right side, a long aberrant branch was found, which arose as an extra anterior divison of the middle trunk and joined peripherally the medial cord at a point where the cord formed the common trunk with the lateral root of the median nerve.These findings were compared with previous data obtained from other primates.     

Purification and Chemical Composition of Reticulate Bodies of the Meningopneumonitis Organisms

Reticulate bodies of the meningopneumonitis (MP) microorganism were purified from L cells 18 hr after infection by the combination of differential centrifugation in 30% sucrose solution and potassium tartrate density gradient centrifugation. It was ascertained by electron microscopy that purified preparations of reticulate bodies obtained were almost entirely free of host-cell components and of infectious elementary bodies of MP microorganisms. Purified reticulate bodies were easily disrupted by mechanical agitation, and it was observed in shadowed preparation that ribosome-like particles 15 mmu in diameter were scattered from broken reticulate bodies. In shadowed preparations, reticulate bodies were found to range in size from 1.0 to 1.6 mu in diameter, but in cross-section the range was 0.5 to 1.0 mu. In these preparations, the purified reticulate bodies were irregular in shape, round or oval, and were composed of rather homogenous, amorphous, or reticulate material with moderate density. Some particles exhibited a less-dense internal structure, in which a coarse fibrous reticulum was seen. Chemical fractionation of (32)P-labeled purified reticulate bodies showed that they contained three times more ribonucleic acid (RNA) than deoxyribonucleic acid, with the RNA being composed primarily of 21S, 16S, and 4S RNA. No infectivity of purified reticulate bodies could be demonstrated.     

A new species and a new subspecies of the stargazer genusGnathagnus from Northwestern Australia

Heretofore the genusGnathagnus (Uranoscopidae) has been composed of three species:G. elongatus (Temminck et Schlegel) from northern Australia to Japan,G. innotabilis (Waite) from Australasia, andG. egregius (Jordan et Thompson) from the western Atlantic Ocean. In this paper, a new species and a new subspecies from northwestern Australia are described and a key to the known species and subspecies of the genus is presented.     

Quantitative analysis of serum IL-6 and its correlation with increased levels of serum IL-2R in HIV-induced diseases

We have devised a luminescence sandwich ELISA for the quantification of IL-6 in both sera and cell culture supernatants, which had a detection limit of 100 fg/ml of test sample. By using the luminescence sandwich-ELISA, low but measurable levels of IL-6 (9.5 pg/ml on average) were found in the sera from normal individuals. The serum levels of IL-6 were elevated in HIV-seropositive asymptomatic carriers (55.5 pg/ml on average), and the IL-6 levels were correlated with the degree of HIV-induced disease progression (AIDS-related complex 106.8 pg/ml on average and (AIDS 283 pg/ml). IL-6 immunoreactivity in the sera of AIDS patients eluted at a 25,000 m.w. major peak, which was biologically active and heat-stable, and a 500,000 m.w. minor peak in size-exclusion HPLC. Interestingly, a significant correlation was observed between the serum IL-6 levels and soluble IL-2R levels. In vitro, HIV infection of PHA-activated PBMC led to enhanced release of IL-6 into the culture supernatants. Moreover, soluble IL-2R release was markedly increased by adding exogenous IL-6, whereas it was decreased by adding the neutralizing anti-IL-6 mAb to the cultures. These results demonstrate that increased IL-6 levels are significantly associated with sIL-2R levels, and suggest a cause of the increased levels of this receptor in patients with HIV infection. Furthermore, both serum IL-6 and serum IL-2R levels in HIV infection reflect the stage of the HIV-induced disease.