Studies on a biological response modifying LYSAT from Propionibacterium avidum KP 40

Propionibacterium avidum KP 40 cells were mechanically disintegrated in order to obtain the soluble immunostimulatory (antineoplastic) LYSAT. Chemiluminescence measurements of human leukocyte function yielded enhanced activation of the cells after incubation with 2.5 and 5 mg of LYSAT. As compared to non-treated controls, administration of LYSAT to BALB/c-mice (1, 2.5 and 5 mg; intraperitoneally, subcutaneously, intranasal; 7, 4 and 2 days prior to challenge) induced a significant enlargement of the spleen as well as significantly reduced sarcoma L-1 lung colonization 14 days after challenge and evidently enhanced chemiluminescence response of peritoneal macrophages.

The role of plasmids in opsonin-independent Staphylococcus aureus-leukocyte interactions

The opsonin-independent phagocytic and bactericidal activity of human polymorphonuclear leukocytes stimulated by two Staphylococcus aureus strains and their variants with differing plasmid patterns was investigated. Interactions between staphylococci and phagocytes were evaluated by chemiluminescence and intracellular killing tests. The results obtained indicate that the presence or absence of certain plasmids can modify staphylococcal phagocytosis and their susceptibility to intracellular killing. Pretreatment of the strains investigated with subinhibitory concentrations of mezlocillin and ofloxacin (10% MIC) influenced these parameters, too.

Antibiotic treatment, intestinal aerobic microflora and experimental sarcoma L-1 growth in Balb/c-mice

The present paper deals with the influence of a 10 days treatment with mezlocillin, piperacillin, cefotaxime, clindamycin or gentamicin on the endogenous intestinal microflora of Balb/c-mice and on the local growth of sarcoma L-1 tumor. Clindamycin and gentamicin demonstrated no influence, whereas cefotaxime and piperacillin caused the eradication of gram-negative resp. gram-positive bacteria but these antibiotics didn't produce a growth inhibition of local L-1 sarcoma tumor. The oral or parenteral application of mezlocillin (a 3 days treatment was sufficient) eradicated the complete aerobic and anaerobic intestinal microflora. This effect was significantly correlated with an increase of the cecum weight and the inhibition of local tumor growth. Possible mechanisms of these effects are discussed.

Opsonin independent interaction of Klebsiella strains with human polymorphonuclear leukocytes

Nine encapsulated Klebsiella strains with different types of fimbriation and their nonencapsulated mutants were tested for their stimulatory potency for human polymorphonuclear leukocytes in the absence of opsonins. The luminol chemiluminescence assay was used for these experiments. It could be shown that the interaction between Klebsiella bacteria and human leukocytes is rather complex depending not only on the presence of capsules but also on the hydrophobicity of Klebsiella surface and on the type of fimbriation existing.

Investigations on opsonin-independent antistaphylococcal activity of human neutrophilic granulocytes, monocytes and lymphocytes

Using cells from 20 healthy human donors the opsonin-independent staphylococcal killing abilities of peripheral blood neutrophilic granulocytes, monocytes and lymphocytes were studied. S. aureus strains T 1 and T 14, S. sciuri strain S I, S. saprophyticus strain S III and S. simulans strain S V were selected for these experiments because of their differing cell wall composition, surface hydrophobicity, protein A content and extracellular enzyme activity spectrum. We could demonstrate a very individual activity range of these cells against staphylococci. On the other hand each staphylococcal strain examined behaved in a very typical way in its susceptibility against the killing by human phagocytes and lymphocytes. Repeated tests in monthly intervals showed that the staphylococcal killing activity range of phagocytes and lymphocytes of a certain healthy donor remains constant and stable.

Effects of ciprofloxacin on the humoral and cellular immune responses in Balb/c-mice

The effects of a 7 days chemotherapy with ciprofloxacin on the humoral and cellular immune responses in Balb/c-mice were examined. Ciprofloxacin-doses used were calculated on a body weight basis from therapeutic dosages in humans. In a dose-dependent way IgM as well as IgG responses were significantly increased. The delayed-type hypersensitivity reaction to oxazolone was not significantly changed. In in vivo as well in vitro experiments ciprofloxacin showed no modulatory activity on the concanavalin A and LPS-induced proliferative activities of mouse spleen cells.

Effect of streptolysin S from Streptococcus pyogenes on contact sensitivity in mice

Streptolysin S, a hemolytic toxin produced by strains of Streptococcus pyogenes, was examined for its effect on cellular immune reaction in mice. The toxin given intraperitoneally for six consecutive days did not influence intensiveness of delayed hypersensitivity to oxazolone which has been used as a model of cellular immune reaction. Streptolysin S injected subcutaneously, closely to lymph nodes directly involved in immune response, markedly suppressed delayed hypersensitivity. Significant inhibition of lymphocyte proliferation by streptolysin S was observed both in vivo as well as in vitro experiments.

[Animal experiment studies on the modification of the immune system by ofloxacin]

Ofloxacin, one of the new group of quinolone antibiotics, was investigated with respect to its possible interactions with different parameters of the immune system. The study was performed in vivo on Balb/c-mice treated for seven days with different doses of the antibiotic and in vitro on human phagocytes from peripheral blood. It was found that ofloxacin does not affect cellular or humoral immune responses in mice. Moreover, human phagocytic cells exposed in vitro even to high concentrations of the drug did not show any significant changes in their function. On the other hand, it was observed that subinhibitory concentrations of ofloxacin induced an increased susceptibility of Staphylococcus aureus 511-Jena to the bactericidal activity of phagocytes.

Small-cell lung cancer and immunochemotherapy with Propionibacterium granulosum KP 45

Seventy-nine patients with small-cell lung cancer were treated with vincristin, methotrexate, and cyclophosphamide in inductive therapy and with methotrexate, cyclophosphamide, and procarbazine in maintenance therapy. Patients were divided at random into two groups: one group received chemotherapy alone and the second group was additionally subjected to systemic immunotherapy with Propionibacterium granulosum strain KP-45. In general, differences in the frequency of therapy response and in duration of remission could not be stated between the two groups of patients, but patients responding to chemotherapy showed a significantly longer remission time and lower complication rates. This benificial effect of chemoimmunotherapy is not related to a direct antitumor activity of the immunomodifier used, but to the lowered risk of myelosuppression and infections. Immunomodulation in combination with chemo- and/or radiotherapy can be recommended for the treatment of small-cell lung cancer.

Suppression of cell-mediated immune reactivity by peptides cleaved from human fibrinogen

Peptides derived from fibrinogen, known from earlier studies to inhibit the stimulation of lymphocytes in vitro and to suppress the humoral immune response in vivo, were investigated for their effect on cell-mediated immune reactivity in mice. An unfractioned mixture of peptides with molecular weights under 3,500 injected intraperitoneally at repeated intervals suppressed the contact hypersensitivity to oxazolone but did not influence the skin inflammatory reaction to croton oil. Local injections of peptides had a stronger effect on contact hypersensitivity. Four 200 micrograms local injections of peptides prior to sensitization abolished the increase in lymph node weight and the uptake of 125I-iododeoxyuridine in the draining lymph node after sensitization. Three previously isolated peptides with vasoactive effects inhibited Con A-stimulated incorporation of 3H-thymidine into spleen cells. The first, a pentapeptide (Ala-Arg-Pro-Ala-Lys), and the second, an undecapeptide (Ser-Glu-Leu-Gln-Lys-Val-Pro-Pro-Glu-Trp-Lys) both with an enhancing effect on microvascular permeability, were more potent than the third, a pentapeptide with slight vasoconstrictive properties (Thr-Ser-Glu-Val-Lys). Cell viability was not altered, as measured by trypan blue exclusion and the release of 86Rb. Accumulating evidence indicates that peptides derived from fibrin may be of importance as modulators of cellular immunoreactivity in a number of clinical conditions.

Antibiotics and immunomodulation: effects of cefotaxime, amikacin, mezlocillin, piperacillin and clindamycin

The effects of 7 days' chemotherapy on the humoral and cellular parameters of the host immune system are described. In Balb/c mice the effects of cefotaxime, amikacin, mezlocillin, piperacillin and clindamycin were examined. The delayed-type hypersensitivity reaction, as well as the IgM and IgG responses, were suppressed by four of the five drugs tested: cefotaxime, amikacin, mezlocillin and piperacillin. One to two weeks after completion of chemotherapy with cefotaxime and amikacin, these parameters returned to normal values, whereas the mezlocillin- or piperacillin-modified reactions were still suppressed after 20 days. The concanavalin A and lipopolysaccharide-induced proliferative activities of mouse spleen cells were suppressed, especially by mezlocillin. The possible consequences of the immunomodulating effects of antibiotics for antimicrobial chemotherapy are discussed.

Rifampicin-induced suppression of antitumor immunity

The effect of rifampicin on transplantable tumor growth and antitumor immunity was studied. The growth of transplantable lung sarcoma was significantly enhanced in mice when rifampicin was given for 7 days or longer. Also, the antitumor effects of preimmunization of the animals with killed tumor cells were abrogated by this antibiotic. In vitro studies showed that spleen cells from tumor-bearing animals expressed significantly lower specific cytotoxicity toward syngeneic tumor cells, when the animals had been previously treated with rifampicin. Also, natural killer activity in healthy animals was diminished in mice receiving the antibiotic.

Effects of cefotaxime, clindamycin, mezlocillin, and piperacillin on mouse sarcoma L-1 tumor

For the study described in the paper, the effects of 10 days' chemotherapy with cefotaxime, clindamycin, mezlocillin, and piperacillin on local tumor growth and on spontaneous or artificial metastatic spread into the lungs were studied. For the animal tumor model Balb/c mice and the mouse sarcoma L-1 tumor were used. Chemotherapy was administered before, immediately after, or some time after the injection of tumor cells. The antibiotic dosage given to mice was calculated on a body weight basis from the doses recommended for humans. Cefotaxime and clindamycin did not influence the animal tumor model, whereas mezlocillin and piperacillin showed positive or negative effects depending on the chemotherapy schedule. In vitro none of the four antibiotics caused cytotoxic activity in cell cultures of mouse sarcoma L-1, human lung cancer E-14, or human malignant melanoma MEW.