The effect of antimicrobial agents on leukocyte chemotaxis

Treatment of generalized bullous pemphigoid with oral tetracycline

BACKGROUND

Although bullous pemphigoid (BP) is a benign self-limited disease, the mainstay of treatment remains systemic steroids, often in combination with immunosuppressive agents. This therapy has considerable potential toxicity, particularly in elderly patients with preexisting problems.

OBJECTIVE

The purpose of this study was to evaluate the efficacy of oral tetracycline as first-choice therapy in patients with BP.

METHODS

Every patient newly diagnosed with generalized BP was treated with oral tetracycline and a midpotency topical steroid.

RESULTS

In all five patients, blister formation was stopped and reepithelialization completed within 1 to 3 weeks. There was no relapse or toxicity noted; follow-up ranged from 16 to 24 months.

CONCLUSION

Oral tetracycline was found to be rapidly efficacious in all patients and devoid of toxicity.

Erythromycin reduces neutrophils and neutrophil-derived elastolytic-like activity in the lower respiratory tract of bronchiolitis patients

Diffuse panbronchiolitis (DPB) is a disease of adults characterized by chronic inflammation of the respiratory bronchioles and the infiltration of chronic inflammatory cells. The clinical efficacy of erythromycin therapy has been demonstrated in DPB patients, but the mechanism of action of this drug is unknown. We investigated the localization of neutrophils in lung biopsy specimens, as well as the cell population and elastolytic-like and chemotactic activity of bronchoalveolar lavage (BAL) fluid, before and after treatment with erythromycin or ampicillin in 11 DPB patients (six biopsy-proven and five clinically diagnosed) and one follicular bronchiolitis patient. These bronchiolitis patients had a high percentage of neutrophil and a high neutrophil-derived elastolytic-like activity in BAL fluid compared with chronic bronchitis patients and normal control subjects. The number of neutrophils and the neutrophil-derived elastolytic-like activity in BAL fluid decreased significantly after treatment with erythromycin along with a significant improvement in pulmonary function studies, although there was no significant change in the chemotactic activity of BAL fluid. No significant reduction in BAL fluid neutrophilia was found in the ampicillin-treated patients. These results suggest an important role for the neutrophil in the pathogenesis or development of bronchiolitis, and also suggest that erythromycin may be useful for the treatment of bronchiolitis through its direct action upon host phagocytic cells.

Dapsone suppresses integrin-mediated neutrophil adherence function

The anti-inflammatory influence of dapsone may involve suppression of neutrophil chemotaxis to selected attractants, but other actions of the drug are likely also involved. We have discovered that dapsone may suppress migration of neutrophils to extravascular sites through inhibition of adherence functions required for neutrophil recruitment. Neutrophil adherence mediated by integrins (CD11/CD18 or Mac-1 family receptors) was measured in vitro in terms of binding of stimulated cells to albumin-coated wells of microtiter plates, using phorbol myristate acetate (PMA) and N-formylmethionyl-leucyl-phenylalanine (FMLP) as stimuli. Adherence was assessed by staining attached cells with crystal violet dye and measuring the dye concentration at OD590 using an automated plate reader. The role of integrins in this assay was confirmed by the ability of anti-integrin antibody to suppress stimulated neutrophil adherence. The OD590 value for cells adhering to albumin in the absence of stimulus and dapsone averaged 0.2 +/- 0.04 (SEM) over five experiments. In the presence of 0.1 microM PMA or 10(-6) M FMLP, the OD590 values averaged 0.88 +/- 0.1 and 0.75 +/- 0.12, respectively. Dapsone did not affect unstimulated neutrophil adherence but, when present with stimulus, produced a dose-related inhibitory effect on adherence. Fifty percent inhibitory doses were approximately 150 micrograms/ml dapsone for both stimuli. Sulfapyridine reproduced the inhibitory effect of dapsone, but two structurally related compounds, hydrochlorothiazide and furosamide, did not. The observed ability of dapsone to inhibit neutrophil chemotaxis under agarose to FMLP and interleukin-8 may also be explained by interference with integrin-mediated adherence required for motility in this assay system. To consider if dapsone might have a similar inhibitory influence on neutrophil adherence in vivo, we tested the stimulated adherence function of neutrophils isolated from three individuals on dapsone therapy for dermatitis herpetiformis. Stimulated adherence of patients' cells averaged less than 40 percent of the control value. Suppression of leukocyte integrin function may therefore also contribute to the ability of dapsone to inhibit neutrophil infiltration in neutrophilic dermatoses.

beta-Lactam antibiotic modulation of murine neutrophil cytokinesis

Fourteen cephalosporins, 11 penicillins and 1 monobactam were evaluated for their in vitro modulation of murine neutrophil cytokinesis. As a result, the beta-lactam antibiotics were placed into 6 groups based on their effect on random (R) and FMLP-directed (D) migration [Group 1 (no effect): cephalosporin C; Group 2 (R-->D decreases): cloxacillin, cefotaxime, ceftazadime, cefuroxime, cephalothin, cephapirin, cephadine, nafcillin, piperacillin, ticarcillin, ampicillin, oxacillin, aztreonam; Group 3 (R increases D-->): cephaloridine; Group 4 (R increases D increases): cefsulodin; Group 5 (R increases D decreases): cefoperazone, cefoxitin, ceftriaxone, 6-amino-penicillanic acid; Group 6 (R decreases D decreases): cefadroxil, cefazolin, penicillin G, methicillin]. Trypan blue exclusion studies showed that inhibition of R and D by Group 6 beta-lactam antibiotics is not due to overt cytotoxicity. beta-lactam antibiotics inhibiting D also increased neutrophil adherence to plastic at a concentration of 1000 microM. Finally, the [Ca++] inhibitor chlorpromazine significantly abrogates beta-lactam- and FMLP-directed migration at a test concentration of 1 microM.

Influences of roxithromycin on cell-mediated immune responses

We investigated the effects of roxithromycin (RXM), a synthesized macrolide antibiotic on murine cellular immune responses by examining the in vitro proliferative response of lymphocytes, interleukin 1 (IL-1) production and interleukin 2 (IL-2) production. RXM was orally administered to BALB/c mice at a dose of 5 mg/kg once a day for 42 days. Spontaneous blastic activity of lymphocytes prepared from mice administered with RXM for 7 days was higher than those from control mice. The activity peaked at the 14th day, and then decreased gradually to control levels by the 42nd day. Time kinetics of lymphocyte blastogenesis to concanavalin A showed a pattern similar to that observed in spontaneous blastic activity. Oral administration of RXM also influenced cytokine production; short-term (for 14 days) administration of RXM enhanced both IL-1 and IL-2 production but long-term (for 42 days) administration inhibited them.

Inhibition of human T-lymphocyte activation by macrolide antibiotic, roxithromycin

Effects of macrolide antibiotic, roxithromycin (RXM) on human lymphocytes in culture were studied. The drug showed a dose-dependent inhibition of 3H-thymidine and 35S-methionine uptake responding to T cell mitogens and purified protein derivative of tuberculin (PPD). Activation by PPD, as assessed by 3H-thymidine uptake, was more sensitive to inhibition than the response to T cell mitogens. The drug produced a loss of blasts when added soon after transformation commenced. Immunosuppressive effects of RXM were further characterized by using four different types of metabolized RXM, RU 28111, RU 39001, RU 44981 and RU 45179. The most potent inhibitor of lymphocyte transformation was RU 45179, followed by RU 44981, RU 39001 and RU 28111 have little activity.

Effects of subminimal inhibitory concentrations of minocycline on neutrophil chemotactic factor production in comedonal bacteria, neutrophil phagocytosis and oxygen metabolism

Comedonal bacteria, Propionibacterium acnes, P. granulosum and coagulase-negative staphylococci (CNS) seem to play an important initiating role in the inflammatory process by producing neutrophil chemotactic factors. The attracted neutrophils, after phagocytosis, release inflammatory factors such as reactive oxygen species (ROS). We investigated the effects of minocycline at subminimal inhibitory concentrations (sub-MIC), i.e. one-tenth MIC, on the production of human neutrophil chemotactic factors in comedonal bacteria, and on several inflammatory parameters of neutrophils, including neutrophil phagocytosis and generation of ROS (O2-, H2O2, OH.). ROS generation in a cell-free, xanthine-xanthine oxidase system was also assessed. Production of neutrophil chemotactic factors in all strains of P. acnes, P. granulosum and CNS were significantly suppressed by sub-MIC minocycline. Sub-MIC minocycline effectively reduced three kinds of neutrophil-generated ROS (O2-, H2O2, OH.). However, neutrophil phagocytosis and the ROS generated in a cell-free system were not markedly changed in the presence of sub-MIC minocycline. The results suggest that sub-MIC minocycline has an anti-inflammatory effect by inhibiting the production of neutrophil chemotactic factors in comedonal bacteria as well as ROS generated by neutrophils in the inflammatory process of acne.

The tetracyclines in dermatology

Tetracycline is one of the most widely used antibiotics. It may share some properties with conventional immunosuppressive drugs and act as an anti-inflammatory agent in the treatment of inflammatory disease. This article reviews cutaneous diseases that have been treated with tetracyclines and their antiinflammatory and immunosuppressive properties.

Topical metronidazole gel. Use in acne vulgaris

Two percent metronidazole and 5% benzoyl peroxide cream was evaluated in four clinical trials. It could be shown that this test cream was significantly better than 5% benzoyl peroxide jelly alone, and significantly better than a placebo cream. It was also shown that 2% metronidazole and 5% benzoyl peroxide cream was equal to systemic oxytetracycline therapy. The advisability of the combination of metronidazole and benzoyl peroxide was simultaneously discussed.

In vitro and ex vivo effects of recent and new macrolide antibiotics on chemotaxis of human polymorphonuclear leukocytes

The effects of five macrolide antibiotics: erythromycin, josamycin, miokamycin, roxithromycin and rokitamycin, on human polymorphonuclear leukocyte (PMN) chemotaxis was studied in vitro and ex vivo. At therapeutic concentrations none of the antibiotics tested affected in vitro PMN chemotaxis. In vitro, erythromycin, josamycin, miokamycin, roxithromycin and rokitamycin decreased PMN chemotaxis significantly only at the concentration of 10 mg/l, which is not usually reached in vivo. Ex vivo studies after the ingestion of therapeutic doses of erythromycin, josamycin, miokamycin and roxithromycin by five volunteers showed a significant effect on PMN chemotaxis. However, further studies are needed to confirm and better evaluate the clinical significance of recent and novel macrolides on PMN chemotaxis.

Effects of subminimal inhibitory concentrations of erythromycin, tetracycline, clindamycin, and minocycline on the neutrophil chemotactic factor production in Propionibacterium acnes biotypes 1-5

Biotypes 1-5 Propionibacterium acnes (P. acnes) strains were grown in the presence of 1/10 minimal inhibitory concentrations (sub-MIC) of erythromycin (EM), tetracycline (TC), clindamycin (CLDM), or minocycline (MINO) and their culture filtrates were assayed for human neutrophil chemotactic activity using Boyden chamber methods. The addition of sub-MIC of MINO to the medium strongly suppressed the neutrophil chemotactic activity of the culture filtrates of P. acnes strains of all biotypes. In contrast, with sub-MIC of EM, TC, or CLDM, the activity of the culture filtrates of P. acnes strains of biotypes 2 and 3 were suppressed but those of biotypes 1, 2, and 5 were not. These results indicate that sub-MIC of MINO is capable of decreasing the inflammatory capacity of P. acnes strains of all biotypes.

The effect of sanguinarine on human peripheral blood neutrophil viability and functions

Human polymorphonuclear cell (PMN) viability, morphology, adherence, chemotaxis, oxidative metabolism, degranulation and phagocytosis were evaluated following treatment with sanguinarine (SANG). SANG was noncytotoxic to PMNs at all concentrations tested (0.31-200 microM). SANG entered the PMNs rapidly without altering the membrane fluidity and localized in the nuclear matrix. SANG (1.56-6.21 microM) inhibited chemotaxis, chemokinesis and adhesion in a dose-dependent manner, with a complete inhibition at 6.2 microM concentration. Concentrations of SANG up to 1.56 microM did not affect PMN oxidative burst; however, higher concentrations were found to inhibit basal as well as PMA-induced superoxide anion generation. The effect of SANG was time- and dose-dependent, and could be reversed if the PMNs were exposed to 12.5 microM or lower concentrations of SANG for less than 5 min. Autologous serum increased the tolerance of PMNs to SANG. Exogenous Ca2+ or Mg2+ did not alter the SANG-mediated inhibition of PMN functions. Treatment of PMNs with 3.12 microM or higher concentrations of SANG also resulted in inhibition of PMN degranulation and phagocytosis. The results suggest that SANG-mediated inhibition of PMN functions, without cytolysis or resultant release of inflammatory mediators, may have clinical implications.

Suppressive effects of linoleic acid on neutrophil oxygen metabolism and phagocytosis

On the basis of recent reports that the proportion of linoleic acid (C18:2Cis 9,12), a free fatty acid, is markedly decreased in acne comedones and that tetracycline is effective against acne comedones by acting directly as an antioxidant on infiltrating neutrophils, we investigated the effect of linoleic acid on several inflammatory parameters of neutrophils, including neutrophil chemotaxis, phagocytosis, and generation of reactive oxygen species (ROS). Linoleic acid significantly decreased phagocytosis and the generation of O2-, H2O2, and OH.by neutrophils, whereas it did not significantly inhibit neutrophil chemotaxis or decrease the ROS levels generated in a cell-free, xanthine-xanthine oxidase system. The present study seems to suggest that decreased levels of linoleic acid in acne comedones contribute, in part, to the worsening of acne inflammation by the failure of low levels of linoleic acid to suppress neutrophil phagocytosis and ROS generation.

Desquamative gingivitis: preliminary observations with tetracycline treatment

Fourteen patients admitted to our clinic were found to have desquamative gingivitis. They were treated with doxycycline monohydrate, a semisynthetic tetracycline, for 6 to 8 weeks. The gingival lesions were recorded photographically and were classified according to severity by means of a four-graded mucosal index system. Biopsies for histologic and immunohistochemical examination were taken initially. Symptoms and clinical changes of the mucosa were recorded during the treatment period. Initial and final mucosal index scores were compared. A statistically significant improvement was obtained after tetracycline treatment.

Absence of minocycline in sebum?

The authors studied the bioavailability of minocycline in sebum and serum. Blood and sebum samples were collected weekly for 6 weeks from ten healthy volunteers taking 200 mg of minocycline every day for 4 weeks. Sebum was collected by direct extraction with petroleum ether from the forehead. After evaporation, sebum was weighed on a scale accurate to 10 micrograms. Determination of minocycline in serum and sebum was performed using a high performance liquid chromatography technique (HPLC), with a better detection limit at 352 nm than at 400 nm (20 ng/ml and 0.324 microgram/ml respectively). Our results contrast with other studies since no minocycline was detected in the sebum samples of treated subjects and microbiological assays of minocycline in sebum were also negative. In our opinion, the current hypothesis claiming that the effectiveness of minocycline in the treatment of acne vulgaris is based on sebaceous secretion should be reconsidered.

Relationship between neutrophil-mediated oxidative injury during acute experimental pyelonephritis and chronic renal scarring

Previous experiments with rats have suggested that pyelonephritic scarring after acute ascending Escherichia coli pyelonephritis partly results from excessive polymorphonuclear leukocyte (PMN) infiltration and activation in the kidney parenchyma. We have studied the role of PMN oxidative metabolism in generating tissue injury during acute pyelonephritis. Rats with acute pyelonephritis were treated with dapsone (25 mg/kg twice daily for 3 days), a compound known to prevent PMN oxidant damage. In vitro, levels of dapsone easily achieved in vivo inhibited myeloperoxidase (MPO)-mediated reactions involving the oxidation of halides to reactive cytotoxic hypohalites (such as MPO-mediated iodination and luminol-enhanced chemiluminescence). In contrast, dapsone had no effect on superoxide production, lysosomal enzyme release, or bacterial killing by activated PMN. In vivo, dapsone treatment had no significant effect on acute pyelonephritis with respect to (i) bacterial counts, (ii) inflammatory swelling, and (iii) PMN infiltration. However, dapsone-treated animals sacrificed 2 months after acute pyelonephritis had a 65% reduction of renal scars when compared with controls. Since dapsone had no antibacterial effect, this protection is compatible with the hypothesis that dapsone prevented oxidant-generated tissue injury due to the extracellular release of the MPO system by activated PMN during acute suppurative pyelonephritis.

Prurigo pigmentosa successfully treated with minocycline

Five patients with prurigo pigmentosa were treated with 100-200 mg minocycline daily. The eruption and pruritus rapidly resolved within a few days or up to a week. There has been no recurrence after stopping medication and we conclude that minocycline is effective for prurigo pigmentosa and safer than dapsone.

Intra-epidermal neutrophilic IgA dermatosis with colitis

We report the association of an intra-epidermal blistering disease of the skin with colitis. Both the skin and large bowel epithelium were infiltrated by neutrophils and eosinophils, and showed intra-epithelial deposition of IgA in an intercellular pattern. The colitis and the blisters responded well to treatment with dapsone.

Side effects of antibiotics on immune response parameters and their possible implications in antimicrobial chemotherapy

Antibiotics may influence immune response by quite different ways. By screening the multitude of publications on this subject, the aim of this overview was to arrive at a basic generalizing statement on the relationship between chemical structure or mode of action of antibiotics and the effect on immune response and to get an indication on whether certain in vitro and/or ex vivo parameters could represent comparable effects under clinical conditions. - The influence of antibiotics on immune response may arise by direct effects on immunocompetent cells, i.e. in the absence of microorganisms, or indirectly by changes in structure or metabolic products of germs induced by subminimal inhibitory concentrations (subMIC's). In the former case, stimulatory and inhibitory effects have been observed on phagocytosis and intracellular killing activity, on antibody production including IgE, on different parameters of cellular immunity (e.g. foodpad swelling reaction, MIF-production, mitogen/antigen induced lymphocyte proliferation and delayed type hypersensitivity skin reaction), on mediator production as interleukins or prostaglandins and the expression of corresponding receptors on immunocompetent cells as well as on the course of experimental infections with primary resistant microorganisms. - Indirect effects are related to the influence of subMIC's of antibiotics on the morphology and structure of microorganisms, on their antigenicity/immunogenicity or on their serosensitivity and enzyme and toxin production. - This overview shows that - according to the actual knowledge - antibiotics may exhibit immunological side effects which, however, can not strictly be attributed to certain chemical structures or to a certain mode of action. - It has to be considered that a literary study comparing the results of different authors is rendered difficult by the often nonhomogeneity of experimental procedures and the fact that little is known yet about immunological side effects of antibiotics in man, i.e. under clinical conditions.

Comparison of miocamycin versus amoxycillin in lower respiratory tract infections in children. Clinical response and effect on natural killer activity

The clinical efficacies of 50 mg/kg.day miocamycin and 60 mg/kg.day amoxycillin were studied in 23 patients aged 3-11.5 years with presumed bacterial infection of the lower respiratory tract (bronchopneumonia and acute bronchitis). During the therapy, which continued for 10 days, non-specific immune function, represented by natural killer cell activity, was monitored by measurement of the rate of lysis induced on target K-562 51Cr-labelled tumour cells. The results confirmed the therapeutical efficacy of miocamycin and amoxycillin in the oral therapy of bronchopneumonia and acute bronchitis in paediatric patients. The natural killer cell activity of patients treated with miocamycin was increased on days 7 and 10 of therapy compared with baseline. This finding did not occur in patients treated with amoxycillin.

Macrolidic antibiotics: effects on primary in vitro antibody responses

The effect of two macrolidic antibiotics, josamycin and erythromycin, on the primary immune response in cultures of human peripheral blood mononuclear cells (PBMC), were studied using a soft agar hemolytic plaque assay. Both compounds induced an appreciable reduction in the primary antibody response in total PBMC cultures. The removal of plastic-adherent cells, however, profoundly modified the effect of macrolides on the immune response. Both josamycin and, to a lesser extent, erythromycin enhanced, rather than suppressed, the antibody response. Furthermore, the macrolide-induced immunodepression in cultures of total PBMC was completely reversed by the addition of catalase (8000 U/ml). Taken together, these findings suggest that the macrolide-induced depression of the antibody response depends upon the presence of adherent monocytic cells and is mediated by the production of hydrogen peroxide.

Erythromycin-induced suppression of pulmonary antibacterial defenses. A potential mechanism of superinfection in the lung

Erythromycin is a broad-spectrum antibiotic commonly used in patients with respiratory infections. Certain of these patients become colonized with new microorganisms and develop superinfections. Antibiotics have a number of effects other than simply killing or inhibiting the growth of bacteria and may have direct effects upon host cells, including phagocytes. In vitro and in vivo studies have demonstrated that erythromycin decreases polymorphonuclear leukocyte (PMN) directed migration. To test the hypothesis that erythromycin inhibits normal PMN migration into the alveoli in response to a bacterial challenge, mice were challenged by aerosol inhalation with Proteus mirabilis or Staphylococcus aureus and injected intravenously with erythromycin (50 or 100 mg/kg). Pulmonary bactericidal activity and total lavaged lung cell and differential counts were determined 4 h after bacterial challenge. In control mice, only 24 +/- 2% of the initial inoculum of P. mirabilis was viable at 4 h. At a dose of 100 mg/kg, lung defenses after erythromycin were ablated, allowing the proliferation of P. mirabilis to 113 +/- 5% of the initial inoculum. The number of PMN obtained by lavage after P. mirabilis challenge was also inhibited by erythromycin in a dose-dependent manner. In untreated animals, 5.0 +/- 0.2 x 10(6) PMN were recovered as compared with 3.1 +/- 0.4 x 10(6) and 1.1 +/- 0.3 x 10(6) with increasing doses of erythromycin. Intrapulmonary bactericidal activity against S. aureus was not impaired by erythromycin.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibiotics and human monocyte function. I. Chemotaxis

The influence of thirteen commonly used antibacterial drugs on the chemotactic responsiveness of human blood monocytes in vitro was investigated. Tetracyklin, trimethoprim and fusidic acid at high concentrations produced a significant inhibition of the monocyte response, whereas normal therapeutic concentrations produced insignificant inhibition. Benzylpenicillin, ampicillin, tobramycin, chloramphenicol, metronidazole, rifampicin, clindamycin, sulfametoxazole, cefotaxime and ofloxacin did not alter monocyte migration. From these observations it can be expected that at normal dosages none of the tested drugs will affect monocyte chemotaxis in vivo.

Erythromycin 2% gel in comparison with clindamycin phosphate 1% solution in acne vulgaris

One hundred two patients with mild to moderate facial acne vulgaris completed a 12-week, investigator-masked, randomized, parallel-group comparison of a gel formation of erythromycin (2%) with clindamycin phosphate 1% solution. Patients were evaluated at a baseline visit and after 4, 8, and 12 weeks of twice-daily treatment. Both medications significantly reduced the numbers of papules and open and closed comedones. No significant differences in lesion count reductions were detected between the treatment groups after 8 and 12 weeks of treatment. By the end of 12 weeks, 48% of the patients in the erythromycin group and 47% in the clindamycin group had good or excellent responses to treatment. No patient was terminated from the study for side effects. Most patients, 65% in the erythromycin 2% gel group and 67% in the clindamycin phosphate 1% solution group, had a favorable impression of the overall cosmetic characteristics of their study medication.

Topical clindamycin phosphate compared with oral tetracycline in the treatment of acne vulgaris

Sixty patients (aged 12-30 years) were enrolled in a 12-week, double-blind, randomized study to compare the efficacy of clindamycin phosphate 1% topical solution with oral tetracycline for the treatment of moderate acne. Forty-four patients (22 in each group) were evaluable. All patients experienced significant reductions in numbers of pustules, papules and inflamed nodules, and there were no significant differences between the two groups. Both treatment regimens were well tolerated, and no systemic side-effects were reported. Topical clindamycin phosphate 1% is considered a safe and effective alternative to oral tetracycline for the treatment of moderate acne vulgaris.

Evolution of a strategy for the treatment of acne

The management of skin disease may differ in different parts of the world, but in most countries, acne should be a most treatable disease. Acne therapy has not evolved in the most logical fashion, but this article reviews our demonstration of risk factors in the treatment of acne. Young patients, male patients, truncal acne, a marked seborrhea, and a low dose (500 mg/day or less) of tetracycline are factors associated with a poorer response and, when oral therapy is stopped, a greater relapse rate. One gram a day of tetracycline, given for 6 months, is the minimum course of oral therapy and should be given along with topical therapy. One of the most widely used topical treatments is benzoyl peroxide, and this presentation was given in honor of Dr. William Pace, who was possibly the first dermatologist to be aware of the benefit of benzoyl peroxide--a fact not adequately recorded in dermatologic history. A small number of patients do not respond well to conventional therapy, but alternative treatments should bring about a successful outcome. Alternative treatments include hormonal therapy (i.e., 2 mg cyproterone acetate plus 50 micrograms ethinyl estradiol; spironolactone, 100 mg twice daily; or isotretinoin, 1 mg/kg). The success of all these treatments bears some relationship to their effect in modulating the etiologic factors of acne: an enhanced sebum production, increased ductal cornification, abnormal bacterial colonization, and the production of inflammation. Isotretinoin is the most beneficial of all drug regimens, and this fact no doubt relates to its favorable effect on all etiologic factors.

Bullous pemphigoid controlled by tetracycline

Two men with nonscarring, persistent, localized bullous pemphigoid, whose eruption is completely controlled with daily doses of oral tetracycline, are described. A review of the literature on persistent, localized bullous pemphigoid is presented. The effects of tetracycline on leukocytes that may play a role in the response of these patients are discussed.

Synergy between RU 28965 (roxithromycin) and human neutrophils for bactericidal activity in vitro

The in vitro effects of RU 28965 (roxithromycin), a new semisynthetic macrolide, on human neutrophil activity were compared with those of erythromycin. RU 28965, at a concentration as low as 0.1 microgram/ml, significantly enhanced the phagocytosis and killing of Staphylococcus aureus by neutrophils. Erythromycin displayed a less stimulating effect in a dose-dependent manner. Phagocytosis of Klebsiella pneumoniae was also increased after incubation of neutrophils with RU 28965, but killing was not altered. Neutrophil chemotaxis, myeloperoxidase activity, and O2 consumption were unchanged in the presence of RU 28965.

In vitro effect of isotretinoin on monocyte chemotaxis

The effect of isotretinoin on the chemotaxis of human monocytes was studied in an in vitro system using a Nucleopore chamber. The chemoattractant used was zymosan-activated serum. Inhibition of monocyte chemotaxis was achieved with isotretinoin in concentrations of 1 X 10(-3) M and 5 X 10(-4) M. It is felt that the improvement seen in patients with inflammatory skin diseases such as cystic acne and acne conglobata who are treated with isotretinoin may in part be a result of this anti-inflammatory action.

Effect of antibiotics on the generation of reactive oxygen species

The relative antioxidant efficacy, in vitro, of several antibiotics was examined by studying their effects on the generation of reactive oxygen species (ROS) using zymosan-stimulated polymorphonuclear leukocytes (PMNL) and the cell-free, xanthine-xanthine oxidase system. The species investigated are superoxide radical anion (O2-.), hydrogen peroxide (H2O2), and hydroxyl radical (OH.). Three tetracyclines (tetracycline HCl, oxytetracycline HCl, and minocycline HCl), erythromycin, cephalexin, penicillin G, chloramphenicol, and streptomycin were used as test drugs. At concentrations comparable to therapeutic blood levels, tetracycline HCl, oxytetracycline HCl, minocycline HCl, and erythromycin inhibited some of the ROS production by PMNL. In the xanthine-xanthine oxidase system, only minocycline HCl suppressed the H2O2 level. Cephalexin, penicillin G, chloramphenicol, and streptomycin did not affect any of the ROS examined at the concentrations tested. The capacity of some of these agents to inhibit ROS generation by PMNL may account, in part, for their efficacy in inflammatory skin diseases such as acne vulgaris. The antioxidant effect of these antibiotics does not stem from their capability to scavenge ROS, but originates rather from their effect on PMNL cell function directly with resultant anti-inflammatory effects on the inflammatory processes.

Contemporary therapy for acne. What, when, and how to prescribe

The use of topical tretinoin (Retin-A) for comedonal lesions, benzoyl peroxide for inflamed papules and pustules, and topical or oral antibiotics for more severe or widespread disease gives excellent results for the majority of patients with acne. At present, oral isotretinoin (13-cis-retinoic acid) (Accutane) should be reserved for patients with severe nodulocystic acne whose condition has not responded to an accepted therapeutic regimen. Good patient rapport and follow-up are essential in the management of this common disease.

An evaluation of a 2% erythromycin ointment in the topical therapy of acne vulgaris

Two hundred eight patients completed a 12-week, multicenter, double-blind, controlled study comparing a 2% erythromycin ointment to its vehicle. Patients were evaluated by inflammatory lesion counts and Cook acne severity grade at the initial visit and at weeks 2, 4, 8, 10, and 12. The 2% erythromycin ointment proved to be statistically more effective than the vehicle in reducing lesion counts and acne severity grade at weeks 4, 8, 10, and 12. The ointment caused few side effects and was well tolerated by most patients.

Oral ibuprofen and tetracycline for the treatment of acne vulgaris

A prospective evaluation of the efficacy and safety of oral ibuprofen and tetracycline hydrochloride was conducted for 8 weeks in patients with moderately severe acne. Sixty-eight patients were randomly assigned in a double-blind fashion to one of four regimens: (1) one 600 mg ibuprofen tablet plus one 250 mg tetracycline capsule four times daily; (2) one 600 mg ibuprofen tablet plus one placebo capsule four times daily; (3) one 250 mg tetracycline capsule plus one placebo tablet four times daily; and (4) one placebo tablet and one placebo capsule four times daily. Sixty patients completed the 8-week study. The mean percent improvement in the groups treated with ibuprofen and tetracycline (56% +/- 5 SE), ibuprofen alone (26% +/- 13 SE), or tetracycline alone (26% +/- 9 SE) was statistically significant. However, only the combination of ibuprofen and tetracycline therapy had an effect statistically better than the placebo response (16+ +/- 11 SE). Adverse effects were transient and were similar in all four groups.

Effect of amoxycillin and doxycycline on function of human granulocytes tested in vitro and on chemotaxis of granulocytes from rabbits given the two antibiotics

The effect of amoxycillin and doxycycline on human granulocyte function was studied in vitro. The antimicrobial agents were added to tests of chemotaxis, random motility, yeast phagocytosis, and killing, at progressing concentrations. The effect was also evaluated in vivo by measuring chemotaxis and random motility (agarose technique) of granulocytes from rabbits injected with these antibiotics. Amoxycillin was shown to have a slightly stimulating effect on chemotaxis, demonstrable only at the highest concentration tested (100 micrograms/ml), and no effect on the other variables. Doxycycline had a dose-related inhibitory effect on chemotaxis, random motility, and phagocytosis, and no effect on killing. Chemotaxis and random motility were slightly, but not significantly, stimulated in vivo when rabbits were given amoxycillin. Chemotaxis (but not random motility) was significantly impaired when the rabbits were given doxycycline.

Inhibition of chemiluminescence in human neutrophils by dapsone

Dapsone at doses of 0.5 to 5.0 micrograms/ml was found to produce a dose-dependent inhibition of opsonized zymosan-induced human polymorphonuclear leukocyte (PMN) chemiluminescence (CL) in vitro. Simultaneous exposure of PMN to dapsone and zymosan was as effective in reducing CL as preincubation of PMN with dapsone. Preincubation of PMN with dapsone followed by washing, resulted in the loss of dapsone-mediated CL inhibition, indicating that dapsone did not permanently alter the CL-generating mechanism and that the drug had to be present to inhibit CL. Dapsone did not absorb light at the wavelength of CL and was not toxic to PMN at concentrations tested. Sodium azide, an inhibitor of myeloperoxidase-mediated CL inhibited PMN CL to the same degree as dapsone. When incubated together with PMN, dapsone and azide did not produce an additive inhibition of CL. These data suggest that inhibition of myeloperoxidase may be the mechanism by which dapsone inhibits PMN CL.

Comparison of topical clindamycin phosphate, benzoyl peroxide, and a combination of the two for the treatment of acne vulgaris

Patients with moderate to severe acne vulgaris were treated for 10 weeks with either topical clindamycin phosphate (1% solution) twice daily, benzoyl peroxide (5% gel) twice daily, or benzoyl peroxide (5% gel) in the morning and clindamycin phosphate (1% solution) in the evening. The effects of each regimen appeared to vary in decreasing specific types of acne lesions, with the combination therapy showing the greatest decrease when all types of lesions were considered. Cutaneous side-effects were greatest with benzoyl peroxide alone during the early weeks of treatment, while the combination therapy displayed no greater incidence of redness, scaling, or itching than clindamycin phosphate alone. All three regimens produced clinical improvements which did not differ significantly from each other.

Rifampin affects polymorphonuclear leukocyte interactions with bacterial and synthetic chemotaxins but not interactions with serum-derived chemotaxins

Three independent experimental approaches support the hypothesis that rifampin competes for receptors on polymorphonuclear leukocytes (PMLs) with small peptide chemoattractants, e.g., N-formylmethionylleucylphenylalanine (FMLP), but not with serum-derived chemoattractants (C5a). First, rifampin inhibited chemotaxis induced with FMLP but reversed the immobilization of PMLs that occurred at high FMLP concentrations. Second, rifampin competed with radiolabeled FMLP for binding sites on PMLs and displaced already-bound radiolabeled FMLP. Third, rifampin blocked and reversed the bipolar shape changes induced in PMLs by FMLP. These effects occurred at concentrations attained during rifampin therapy and were not due to rifampin toxicity. In contrast, no effect of rifampin was observed on serum-derived chemoattractants (C5a) in any of the three systems. The evidence suggests, therefore, that rifampin is a ligand for FMLP-type receptors on PMLs.

Chemotaxis: basic aspects of methodology, mechanisms and pathology

This review is an attempt to discuss the basic conceptual tools that are a prerequisite for any clinical study of chemotactic defects. They include familiarity with definitions of common terms and with the merits and drawbacks of the several possible in vivo and in vitro assay methods. Cellular mechanisms involved in locomotion are complex. They include basic requirements for cell metabolism as well as receptor recognition, attachment to surfaces and contraction of the cytoskeleton of the cell. Of the many chemotactic factors reported, few are well characterized and universally agreed upon. Similarly, with the use of more stringent criteria, a number of clinical defects of chemotaxis have proven transitory or even artifactual.