Absorption of Escherichiacoli endotoxin from the small intestines of mature non-pregnant gilts

The small intestines of 31 mature crossbred gilts were infused with $\text{Escherichia}$$\text{coli}$ endotoxin through permanent jejunostomies. A total of 86 infusions were done. The endotoxin was absorbed after 4 infusions. Evidence of absorption included variations in body temperatures, decline in white blood cell counts, detection of the endotoxin in circulating blood plasma samples by a limulus amebocyte lysate gelation test, and abnormal clinical signs. $\text{E.}$$\text{coli}$ endotoxin placed in the small intestines of normal, healthy, mature gilts does not readily cause illness.     

Does simian virus 40 DNA integrate into cellular DNA during productive infection?

Late after infection of permissive monkey cells by simian virus 40 (SV40), large amounts of SV40 DNA (30,000 to 220,000 viral genome equivalents per cell) can be isolated with the high-molecular-weight fraction of cellular DNA. Hirai and Defendi (J. Virol.9:705-707, 1972) and H?lzel and Sokol (J. Mol. Biol. 84:423-444, 1974) suggested that this SV40 DNA is covalently integrated into the cellular DNA. However, our data indicate that the high-molecular-weight viral DNA is composed of tandem, "head-to-tail" repeats of SV40 DNA and that very little, if any, of this viral DNA is covalently joined to the cellular DNA. This was deduced from the following experimental findings. The size of the SV40 DNA associated with the high-molecular-weight cellular DNA fraction is greater than 45 kilobases, based on its electrophoretic mobility in agarose gels. In this form the SV40 DNA did not produce heteroduplex structures with a marker viral DNA (an SV40 genome with a characteristic deletion and duplication). After the high-molecular-weight DNA was digested with EcoRI or HpaII endonucleases, enzymes which cleave SV40 DNA once, more than 95% of the SV40 DNA migrated as unit-length linear molecules and, after hybridization with the marker viral DNA, the expected heteroduplex structures were easily detected. Digestion of the high-molecular-weight DNA fraction with restriction endonucleases that cleave cellular, but not SV40. DNA did not alter the electrophoretic mobility of the polymeric SV40 DNA, nor did it give rise to molecules that form heteroduplex structures with the marker viral DNA. Polymeric SV40 DNA molecules produced after coinfection by two physically distinguishable SV40 genomes contain only a single type of genome, suggesting that they arise by replication rather than by recombination. The polymeric form of SV40 DNA is highly infectious for CV-1P monolayers (6.5 X 10(4) PFU per microgram of SV40 DNA), yielding virtually exclusively normal, covalently closed circular, monomer-length DNA. Quite clearly these cells have an efficient mechanism for generating monomeric viral DNA from the SV40 DNA polymers.     

Synthesis of acetylenic sugars and uronic acids via two-carbon chain extension of d-ribose

Treatment of methyl β-d-ribofuranoside with acetone gave methyl 2,3-O-isopropylidene-β-d-ribofuranoside (1, 90%), whereas methyl α-d-ribofuranoside gave a mixture (30%) of 1 and methyl 2,3-O-isopropylidene-α-d-ribofuranoside (1a). On oxidation, 1 gave methyl 2,3-O-isopropylidene-β-d-ribo-pentodialdo-1,4-furanoside (2), whereas no similar product was obtained on oxidation of 1a. Ethynylmagnesium bromide reacted with 2 in dry tetrahydrofuran to give a 1:1 mixture (95%) of methyl 6,7-dideoxy-2,3-O-isopropylidene-β-d-allo- (3) and -α-l-talo-hept-6-ynofuranoside (4). Ozonolysis of 3 and 4 in dichloromethane gave the corresponding d-allo- and l-talo-uronic acids, characterized as their methyl esters (5 and 6) and 5-O-formyl methyl esters (5a and 6a). Ozonolysis in methanol gave a mixture of the free uronic acid and the methyl ester, and only a small proportion of the 5-O-formyl methyl ester. Malonic acid reacted with 2 to give methyl 5,6-dideoxy-2,3-O-isopropylidene-β-d-ribo-trans-hept-5-enofuranosiduronic acid (7).     

Lymphokines in sensitized rats. III. Influence of prednisolone treatment of lymph node and spleen architecture in sensitized rats and upon MIF release in vitro.

The influence of prednisolone (corticosteroid, C.S.) treatment upon established cell-mediated immunity (CMI) induced by complete Freund's adjuvant (CFA) has been studied in rats by using in vitro migration inhibitory factor (MIF) assays, type IV skin reactions, and regional lymph node and spleen histology. Additionally, changes in the mononuclear-polymorphonuclear ratio of peripheral blood and T-cell accumulation in bone marrow in response to C.S. treatment have been determined. These results have been evaluated by comparison with equivalent experiments upon animals treated with anti-rat lymphocyte serum (ALS), oxisuran, or 2-[(methylsulfinyl)-acetyl]pyridine, which selectively suppresses CMI. The results suggest the existence of a population of “educated” T-cells in the thymic cortex of sensitized rats, and they suggest that prolonged C.S. administration does not suppress T-effector cells involved in established CMI but, rather, affects lymphocyte and monocyte migration patterns, including the migration of educated T-cells from the thymic cortex into other tissue compartments.     

Both interleukin-1 alpha and interleukin-1 beta are involved as accessory signals in primary antigen (tetanus toxoid) induced human T-cell activation

The function of interleukin-1 alpha and interleukin-1 beta (IL-1 alpha, IL-1 beta) in tetanus toxoid (TT) induced T-cell proliferation in cultures of peripheral blood mononuclear cells (PBL) obtained from healthy donors was assessed by using neutralizing antisera to IL-1 alpha and IL-1 beta. The neutralizing capacity and the specificity of the IL-1 antisera were tested by the use of the thymoma EL-4 NOB-1 cell line. Antisera to IL-1 beta effectively neutralized the proliferative capacity of human recombinant IL-1 beta but not of human recombinant IL-1 alpha and vice versa. Addition of either anti-IL-1 beta or anti-IL-1 alpha antiserum to the culture medium hardly affected TT induced T-cell proliferation. However, the proliferative T-cell response was consistently attenuated when a combination of IL-1 alpha and IL-1 beta antiserum was used. The antisera were never capable of completely abolishing the T-cell response to TT. We conclude that (a) IL-1 alpha and IL-1 beta are both necessary accessory signals for T-cell proliferation to antigen in vitro; (b) in T-cell proliferation IL-1 alpha and IL-1 beta are interchangeable; and (c) T-cell proliferation to antigen is only partially dependent on IL-1 as signal.     

Streptococcal cell wall-induced arthritis and adjuvant arthritis in F344----Lewis and in Lewis----F344 bone marrow chimeras

Streptococcal cell wall (SCW)-induced arthritis and adjuvant arthritis (AA) are rat models for chronic, erosive polyarthritis. Both models can be induced in susceptible Lewis rats, whereas F344 rats are resistant. In AA as well as in SCW arthritis, antigen-specific T lymphocytes have been demonstrated to be crucial for chronic disease. In this communication we describe our studies to probe the cellular mechanism responsible for the difference in susceptibility of Lewis and F344, using bone marrow chimeras. By transplanting bone marrow cells from F344 into lethally irradiated Lewis recipients, Lewis rats were rendered resistant to SCW arthritis induction. F344 rats reconstituted with Lewis bone marrow, i.e., Lewis----F344 chimeras, develop an arthritis upon SCW injection. For AA comparable results were obtained. These data suggest that both resistance and susceptibility to bacterium-induced chronic arthritis are mediated by hemopoietic/immune cells and that the recipiental environment does not influence the susceptibility to chronic joint inflammation.