Monocytes, macrophages and dendritic cells (DCs) are developmentally related regulators of the immune system that share the monocyte-macrophage DC progenitor (MDP) as a common precursor. Unlike differentiation into DCs, the distal pathways for differentiation into monocytes and monocyte-derived macrophages are not fully elucidated. We have now demonstrated the existence of a clonogenic, monocyte- and macrophage-restricted progenitor cell derived from the MDP. This progenitor was a Ly6C(+) proliferating cell present in the bone marrow and spleen that generated the major monocyte subsets and macrophages, but not DCs or neutrophils. By in-depth quantitative proteomics, we characterized changes in the proteome during monocyte differentiation, which provided insight into the molecular principles of developing monocytes, such as their functional maturation. Thus, we found that monocytes and macrophages were renewed independently of DCs from a committed progenitor.

Monocytes and tumor-associated macrophages are part of the myeloid family, a group of hematopoietic derived cells. Monocytes are direct precursors of hematopoietic stem cell-derived macrophages. After their recruitment into the tumor tissue, they can differentiate into tumor-associated macrophages, a very heterogeneous cell population in terms of phenotype and pro-tumor function, supporting tumor initiation, local progression and distant metastasis. Therefore, targeting monocytes and macrophages is a promising immunotherapeutic approach. This review will focus on the development of monocytes as macrophage precursors, the functions of tumorassociated macrophages and the possibility of interfering with tumor development and progression by targeting these myeloid cells.

We consider the one-loop five-graviton amplitude in type II string theory calculated in the light-cone gauge. Although it is not possible explicitly to evaluate the integrals over the positions of the vertex operators, a low-energy expansion can be obtained, which can then be used to infer terms in the low-energy effective action. After subtracting diagrams due to known D 2n R 4 terms, we show the absence of one-loop R 5 and D 2 R 5 terms and determine the exact structure of the one-loop D 4 R 5 terms where, interestingly, the coefficient in front of the D 4 R 5 terms is identical to the coefficient in front of the D 6 R 4 term. Finally, we show that, up to D 6 R 4 ∼ D 4 R 5 , the ǫ 10 terms package together with the t 8 terms in the usual combination (t 8 t 8 ± 1 8 ǫ 10 ǫ 10 ).

Acyclovir (aciclovir) is a nucleoside analogue antiviral drug related to cytarabine, idoxuridine, trifluridine and vidarabine. In common with these earlier antivirals, acyclovir is active against some members of the herpesvirus group of DNA viruses. The efficacy of topical acyclovir has been convincingly demonstrated in ocular herpetic keratitis, and in initial and primary initial genital herpes infection, but little or no clinical benefit was seen when non-primary initial genital infections were assessed separately. Acyclovir ointment demonstrated little benefit in recurrent genital herpes but topical acyclovir cream decreased the course of the infection by 1 to 2 days. Orally and intravenously administered acyclovir were beneficial in initial genital herpes infections, and oral therapy shortened the duration of recurrent infections by 1 to 2 days but did not ameliorate pain. In non-immunocompromised patients with recurrent herpes simplex labialis, generally little clinical benefit was seen with the use of topical acyclovir ointment even when therapy was initiated during the prodromal phase, while topical acyclovir cream effected small but significant improvements in the clinical but not the symptomological course of the disease. However, in immunocompromised patients, both intravenous and topical acyclovir shortened the clinical course of herpes simplex virus infections occurring mainly on the lips, oral mucosa and face, and prophylaxis with either oral or intravenous acyclovir suppressed the appearance of recurrent lesions from latent virus for the period of drug administration, but acyclovir did not eradicate latent herpesviruses. In non-immunocompromised patients, intravenous acyclovir was shown to decrease the acute pain of zoster, especially in the elderly, but postherpetic neuralgia was not ameliorated. When immunocompromised patients were studied, intravenous acyclovir inhibited the progression of zoster infections and shortened the healing time and duration of viral shedding in patients with cutaneous disseminated zoster. However, acute and post-herpetic pain were not significantly affected. Well designed controlled studies are underway to establish the efficacy of acyclovir in herpes simplex encephalitis and cytomegalovirus infections in immunocompromised patients, infections due to Epstein-Barr virus, and neonatal herpesvirus infections. Despite some aspects of the drug's use which require further clarification, acyclovir will make a major impact on the treatment of herpesviral infections. Barring unexpected findings with wider clinical use, it will become the agent of choice in several conditions.