Redistribution of Lyt-bearing T cells in acute murine experimental allergic encephalomyelitis: selective migration of Lyt-1 cells to the central nervous system is associated with a transient depletion of Lyt-1 cells in peripheral blood

Experimental allergic encephalomyelitis (EAE) was induced in SJL/J mice by using two injections of spinal cord homogenate in incomplete Freund's adjuvant supplemented with mycobacteria. Analysis of circulating Lyt-bearing subsets by indirect immunofluorescence during the course of acute EAE revealed the following: 1) during the pre-clinical phase of EAE (1 to 2 days before the onset of paralysis), there was a decrease in the percentage of Lyt-1- but not of Lyt-2-bearing cells in peripheral blood, and of both Lyt-1- and Lyt-2-bearing cells in spleen; 2) with the onset of clinically evident EAE, there was a decrease in both Lyt-1 and Lyt-2 cells in peripheral blood and an increase in the percentage of Lyt-1-bearing cells in pooled inguinal and axillary lymph node; and 3) after these early changes, there was a rapid reconstitution of the percentages of total Lyt-bearing cells and of both Lyt-1- and Lyt-2-bearing cells in peripheral blood. Immunohistochemical analysis of the central nervous system infiltrate revealed that the earliest lesions consisted predominantly of Lyt-1 T lymphocytes, with few Lyt-2 cells present. These results demonstrate that the influx of cells of the Lyt-1 inducer subset to the central nervous system in acute EAE is accompanied by a transient decrease in Lyt-1 cells in peripheral blood.     

Evaluation of H2O activity in the free or phosphorylated catalytic site of Ca2+-ATPase

The sarcoplasmic reticulum Ca2+-ATPase catalyses a reversible calcium transport coupled to phosphate transfer between ATP and water. It has been proposed [Biochemistry (1980) 19, 4252-4261] that the reactivity of the acyl-phosphate bond is dependent on the water activity within the catalytic site. We have tested this hypothesis and found that the polarity in the free catalytic site is lower than that of water, a further and large decrease is observed when the enzyme is phosphorylated by Pi. Phosphorylation by ATP indicates that this polarity change is specifically associated with the formation of the ADP-insensitive phosphoenzyme.     

CCK nerve terminals in the rat striatal and limbic areas originate partly in the brain stem and partly in telencephalic structures

After direct injection of colchicine into the rat rostral caudateputamen, levels of cholecystokinin-like immunoreactive (CCK-IR) material in this part of the nucleus are significantly lowered, and CCK-IR neuronal cell bodies are not demonstrable in the caudateputamen, although numerous ones are revealed in some adjacent telencephalic regions. Direct injection of kainic acid into the rostral caudate-putamen is not followed by a decrease of CCK-IR material in the lesioned region. Twenty one days after injection of 6-hydroxydopamine into the rat ventral mesencephalon, a significant decrease of CCK-IR material is observed in the frontal pole, the pyriform cortex, the nucleus accumbens and the ventral mesencephalon itself, but not in the caudate-putamen. After brain stem hemitransection, no decrease in CCK-IR material is observed in the rostral caudate-putamen.     

Interleukin 2-dependent natural killer (NK) cell lines from patients with primary T cell immunodeficiencies

Bulk cultured cell lines with natural killer (NK) activity were derived by in vitro culture with interleukin 2-containing conditioned medium (IL 2-CM) of peripheral blood mononuclear leukocytes (PBL) from patients with primary T cell deficiencies. Lines were developed from three patients with severe combined immunodeficiency (SCID) and one patient with Nezelof's syndrome and contained several populations of cells with distinct phenotypes. All lines contained a cell population expressing the Leu-5 (50K) (sheep red blood cell receptor), 3A1 (40K), and OKT10 antigens, but lacking the pan T cell antigens Leu-1 (67K) and Leu-4 (19K) as well as the markers of T cell subsets Leu-2a (32K) and Leu-3a (56K). These cells failed to express the Leu-7 antigen and only weakly expressed OKM1. In addition, one line contained a population of Leu-5+, 3A1+, OKT10+, Leu-2a+, Leu 1-, and Leu 4- cells. Three of the lines also contained populations with classic T cell (Leu-1 and-Leu 4+) phenotypes. The lines were enriched in NK activity compared with the PBL from which they were derived. Their growth was strictly dependent on IL 2-CM. Highly purified IL 2, lacking any other detectable protein contaminants or lymphokine activities, was capable of supporting the growth of the Leu-5+, 3A1+ "null" cell populations from these lines without alteration in their functional activity or phenotype. Thus, studies of in vitro expanded cell lines from patients with severe disorders of T cell function and thymic involution indicate that this "null" cell population does not require thymic maturation to develop its effector function. This "null" cell population can be maintained in vitro in the presence of IL 2. This finding is analogous to the data obtained from study of NK cells in athymic (nude) mice.     

Nuclear activity during oogenesis in sea urchins

Summary Early meiotic stages of Arbacia punctulata oocytes have revealed the presence of synaptinemal complexes in the chromosomes, which persist through zygotene-pachytene. The synaptinemal complexes conform broadly to the usual tripartite structures found in other higher forms. In addition, nuclei at these stages consist of a small nucleolus and dense bodies of varying sizes. The nucleolus is fibrillar in texture throughout and does not seem to incorporate Uridine-5-³H after pulse labeling, whereas the chromosomes are labeled. The nucleolar label is visualized at diplotene stages and onwards. The nuclear envelope differentiates by the appearance of numerous nuclear pore complexes with dense material in the annuli, and the chromosomes become markedly diffused. At vitellogenesis stage the nucleolus and chromatin become highly labeled after pulse incorporation of Uridine, indicating synthesis of ribosomal and chromosomal RNAs.This investigation was supported by grants No. A-5049, A-3624 and D-17 from National Research Council, Canada, grant No. DRB-9340-05 (U6) from Defense Research Board, Canada, and grant No. DRG-918 AT from Damon Runyon Memorial Fund for Cancer Research.     

The utilization ofL-amino acids as carbon source by yeasts of the generaHansenula andTrichosporon

The assimilation of singleL-amino acids as carbon source in the absence of added nitrogen has been studied for all the described species in the generaHansenula andTrichosporon. The range in the number of amino acids used by individual species varied in the two genera, inHansenula from 0 to 6, inTrichosporon from 0 to 16. These characters were considered in relation to the phylogenetic scheme and ecological origin ofHansenula.     

Arginine utilization by Chlorella autotrophica and Chlorella saccharophila

Chlorella saccharophila can utilize the amino acids arginine, glutamate. ornithine and proline as sole sources of nitrogen for growth. By comparison C. autotrophica utilized only arginine and ornithine. Following osmotic shock of Chlorella autotrophica from 50 to 150% artificial seawater rapid synthesis of proline (the main osmoregulatory solute in this alga) occurred in cells grown on arginine or citrulline. However, little proline synthesis occurred in ornithine-grown cells. Distribution of radiolabelled carbon from [¹⁴C]-arginine assimilation following osmotic shock of C. autotrophica agrees with the following pathway of arginine utilization: arginine→citrulline→ornithine→glutamate semialdehyde→pyrroline-5-carboxylate→proline. These 4 steps are catalysed by arginine deiminase (EC 3.5.3.6), citrullinase (EC 3.5.1.20), ornithine transaminase (EC 2.6.1.13) and pyrroline-5-carboxylate reductase (EC 1.5.1.2), respectively. Of these 4 enzymes, only arginine deiminase and pyrroline-5-carboxylate reductase were detected in the crude extract of the 2 Chlorella species. Arginine deiminase did not require specific cations for optimal activity. The deimi-nase showed maximal activity at pH 8.0 and followed Michaelis-Menten kinetics with an apparent K_m for L-arginine of 0.085 m M for the C. autotrophica enzyme and 0.097 m M for that of C. saccharophila. The activity of arginine deiminase was not influen-ced by growing C. saccharophila on arginine. Ornithine competitively inhibited arginine deiminase with an apparent K, of 2.4 m M for the C. autotrophica enzyme, and 3.8 m M for that of C. saccharophila . Arginine utilization by Chlorella is discussed in relation to that of other organisms.     

Steroid and gonadotropin hormone levels in young African women with filarial infection

Serum levels of dehydroepiandrosterone sulfate (DHEAS), testosterone (T), progesterone (P), estradiol (E2), prolactin (PRL), cortisol (F) and gonadotropins (FSH, LH) were analysed by radioimmunoassay for 125 schoolgirls aged 14-16, in a zone of endemic filariasis 3 days after menses. Two groups were identified: the infected group in which 38 subjects had circulating Loa loa and or Mansonella perstans microfilariae as determined by the Knott's concentration technique, and the non-infected group (87 subjects without microfilaremia). All results are expressed as the mean +/- SD. No significant difference was found between the two groups for age (14.47 +/- 1.37 yr vs 14.50 +/- 1.37 yr) or for body wt (46.10 +/- 8.45 kg vs 47.06 +/- 8.26 kg). There was a tendency to lower levels of DHEAS in the infected group by comparison with controls (54.92 +/- 37.34 micrograms/dl vs 66.80 +/- 47.18 micrograms/dl) while in the same infected group more subjects had higher levels of prolactin by comparison with the control group (10.85 +/- 14.16 ng/ml vs 9.80 +/- 5.56 ng/ml). Testosterone, progesterone, estradiol levels and the LH/FSH ratio were lower in the infected group than in the non-infected group (P: 0.25 +/- 0.12 ng/ml vs 0.33 +/- 0.20 ng/ml, P less than 0.025; T: 0.55 +/- 0.17 ng/ml vs 0.62 +/- 0.19 ng/ml, P less than 0.05; E2: 32.95 +/- 19.63 pg/ml vs 66.98 +/- 54.83 pg/ml, P less than 0.001; LH/FSH: 0.91 +/- 0.44 vs 1.30 +/- 0.84, P less than 0.005) respectively. No significant difference was found between the two groups for F; however FSH levels correlated negatively with F levels only in the microfilaremia group (r = -0.38, n = 38, P less than 0.05). Our results suggest that the presence of microfilaremia in our subjects may have contributed to reduced steroid levels, perhaps by involvement of the cyclic AMP kinase system. These observations may explain the delayed menarche and androgen secretion found during puberty in a similar population living in the same zone of endemic filariasis. Microfilaremia should therefore be considered an environmental factor which mediates endocrine disorders in subjects living in tropical filariasis areas.