James G. Hirsch

Effects of cytochalasin B on polymorphonuclear leucocyte locomotion, phagocytosis and glycolysis☆

Abstract Observations have been made on the inhibitory action of cytochalasin B (CB) on locomotion, phagocytosis and glycolysis in human, horse, and rabbit polymorphonuclear leucocytes (PMNs). Locomotion in all three species was suppressed by as little as 0.3 μg/ml CB and completely blocked by 3 μg/ml, as judged by direct observation or by a Millipore filter assay system. Phagocytosis was evaluated morphologically as well as in a bactericidal system. Three μg/ml CB suppressed, but did not completely block, phagocytosis by horse and human cells; increasing the concentration of CB to 40 μg/ml exerted little additional suppression of phagocytic capacity. Rabbit exudate cells ingested and killed certain species of bacteria Staph. aureus or Salmonella less effectively than did horse or human cells; in these instances CB did not alter the killing rate significantly CB did inhibit the killing of E. coli by rabbit cells. Three μg/ml CB resulted in a partial inhibition of several glycolytic parameters, i.e., glucose utilization, lactate production, and CO 2 production from C-1 or C-6 labeled glucose. These parameters were inhibited more than 75 % by 10 μg/ml CB. Studies made thus far indicate that CB probably suppresses glycolysis by interfering with glucose transport or phosphorylation. Comparison of the inhibition of various parameters by CB and by other metabolic inhibitors suggests that the glycolytic inhibition by CB is probably not the primary drug action responsible for the altered locomotion and phagocytosis.

Cytochalasin B: Inhibition of D-2-Deoxyglucose Transport into Leukocytes and Fibroblasts

Cytochalasin B inhibits transport of D-2-deoxyglucose and of glucosamine into kukocytes, but does not impair uptake of kucine by these cells. This inhibitory action is rapid and reversible, and results in suppression of glycolysis. Cytochalasin B also blocks transport of D-2-deoxyglucose, but not of leucine, into mouse L strain fibroblasts.

Copper on Intrauterine Devices Stimulates Leukocyte Exudation

Metallic copper in the uterine or abdominal cavities of rats or monkeys stimulates an impressive local exudation of polymorphonuclear leukocytes. This cellular response to copper persists for at least 7 months, without significant local tissue damage or detectable systemic effects on the test animal. This finding provides a possible explanation for the capacity of copper to increase impressively the antifertility effect of polyethylene intrauterine contraceptive devices.

Restoration of Antibody-Forming Capacity in Cultures of Nonadherent Spleen Cells by Mercaptoethanol

Populations of mouse spleen cells, without those cells that adhere to glass or plastic, exhibit little or no capacity for formation of antibody to sheep erythrocytes in the Mishell-Dutton culture system. When 5 x 10-5M mercaptoethanol is added to the culture medium, the antibody-forming capacity of these nonadherent spleen cells is restored to that of unfractionated spleen cells.

ADRENAL STEROIDS AND INFECTION: THE EFFECT OF CORTISONE ADMINISTRATION ON POLYMORPHONUCLEAR LEUKOCYTIC FUNCTIONS AND ON SERUM OPSONINS AND BACTERICIDINS*

Abundant clinical and laboratory experience has established clearly the increased susceptibility to certain infections of animals receiving large doses of cortisone (1-3). There is general agreement that excessively high levels of glucocorticoid hormones diminish the efficiency of host resistance to microbial invasion, but considerable uncertainty remains as to the precise alterations and mechanisms involved (4, 5). Suppression of the inflammatory reaction, impaired function of phagocytic cells, and lowering of antibody levels have all been incriminated to explain the reduced ability to handle microbes of the animal receiving large doses of cortisone. Host resistance to infections is based ultimately on the activity of many systems: phagocytic cells (polymorphonuclear leukocytes, fixed and wandering macrophages) ; serum factors (bactericidins, complement, antibody); and the microenvironment of tissue spaces (vascular and neural functions, chemical composition). This communication presents the results of experiments in which the effect of cortisone administration was studied on function of certain of these host resistance systems-namely, the polymorphonuclear leukocyte and serum bactericidins and opsonins.

The treatment of sarcoidosis with chloroquine

Abstract Chloroquine has been administered to seven patients with chronic sarcoidosis. In each instance there was considerable improvement of the cutaneous lesions. Regression of extracutaneous lesions was more variable, but improvement was often observed; this was particularly true of mucous membrane and thoracic node involvement. Associated with the clinical response, elevated sedimentation rates and high gamma globulin levels returned toward normal. It is suggested that chloroquine may be a useful drug for the treatment of many patients with sarcoidosis, and further studies are in progress to define the situations in which its use is of most benefit.

Studies on attachment and ingestion phases of phagocytosis of Mycoplasma pulmonis by mouse peritoneal macrophages.

Summary Studies have been made on factors which influence attachment of Mycoplasma pulmonis to the surface of mouse macrophages in vitro, and on factors which determine whether or not the attached microorganisms are ingested. Attachment of mycoplasmas exhibited few specific requirements. Attachment occurred in media containing no broth, serum, or divalent cations, and it was not blocked by proteolytic enzymes, neuraminidase, lysozyme or by exposure of the mycoplasmas to glutaraldehyde, to heat, or to repeated freezing and thawing. Only glutaraldehyde fixation of both the macrophages and the mycoplasmas, or use of a nonionic sucrose medium prevented attachment. In enriched tissue culture medium, the attached mycoplasmas resisted ingestion by the macrophages. This resistance was lost if the mycoplasmas were damaged or killed in various ways. Mycoplasmas treated with proteolytic enzymes under conditions not lethal for the organisms became susceptible to ingestion by macrophages, suggesting the presence of an antiphagocytic surface protein. Mycoplasmas were also rendered susceptible to ingestion on exposure to nonlethal concentrations of antimycoplasma IgG antibody; F(ab′)2 fragments did not promote engulfment, suggesting that the Fe portion of the antibody molecule was important in the ingestion process, probably by reacting with Fc receptor sites on the macrophage.

Studies on transport of macromolecules and small particles across mesothelial cells of the mouse omentum: I. Morphologic aspects

Abstract The central portion of the mouse omentum is a fenestrated, membrane-like structure composed of two sheets of mesothelial cells enclosing a thin (1–2 μm) connective tissue space which contains collagen and a few mast cells and macrophages. The mesothelial cells are large and flat with a central elongated nucleus and a large expanse of thin cytoplasm. Mesothelial cells are connected to one another by junctions of the adherent type. The thin cytoplasmic regions contain huge numbers of small vesicles about 100 nm in size, many of which are connected to the connective tissue or the peritoneal surface by narrow necks. Various electron-opaque products were administered intraperitoneally, and observations were made on their transport into the omentum. At 5 min, Thorotrast was localized mainly at the peritoneal surface and in mesothelial cell vesicles connecting with or near to the peritoneal surface; 10–20 min after injection Thorotrast was also found in the connective tissue space and in mesothelial cell vesicles opening into this space. Similarly 10–20 min after ferritin injection, the particles were distributed in vesicles throughout the mesothelial cell and in the collagen layer. The observations indicate that certain macromolecules and small particles are transported by vesicles across mesothelial cells of the omentum.

Studies on transport of macromolecules and small particles across mesothelial cells of the mouse omentum: II. Kinetic features and metabolic requirements☆

Abstract A method has been devised for maintaining mouse omentum in vitro for several hours with preservation of its transport function and retention of the transported macromolecular material. The uptake of ferritin- 55 Fe was essentially linear during the first 2–3 h, at a rate proportional to the concentration in the medium. Transport of the ferritin- 55 Fe was moderately suppressed by the presence of an excess of unlabelled ferritin, by reduction of the temperature to 15 °C, by 8 × 10 −4 M fluoride, and by 1 × 10 −3 M 2, 4-dinitrophenol. Transport was somewhat inhibited by 60 μg/ml cycloheximide and by 1–10 μg/ml puromycin. Sodium azide at 5 × 10 −4 M did not significantly alter transport. These findings suggest that transport of ferritin across mesothelial cells is an active process, perhaps accompanied by a minor element of diffusion.

Ciliocytophthoria Relationship to Viral Respiratory Infections of Humans

Summary1) Sputum specimens from patients with acute and chronic pulmonary diseases were examined cytologically by the Papanicolaou technic. Certain abnormalities in exfoliated ciliated epithelial c...