Mast Cells Recruited to Mesenteric Lymph Nodes during Helminth Infection Remain Hypogranular and Produce IL-4 and IL-6
JOURNAL OF IMMUNOLOGY
2013; 190 (4): 1758-1766
Desensitization regimens for drug allergy: state of the art in the 21st century
CLINICAL AND EXPERIMENTAL ALLERGY
2011; 41 (12): 1679-1689
Mast cells (MC) and basophils share expression of the high-affinity receptor for IgE (Fc?RI) but can be distinguished by their divergent expression of KIT and CD49b. In BALB/c mice, MC lineage cells expressing high levels of Fc?RI by flow cytometry were seen only in bone marrow whereas those expressing intermediate levels of Fc?RI were present in bone marrow and spleen of naive mice and in mesenteric lymph nodes (mLN) of Trichinella spiralis-infected mice. These Fc?RI(+)KIT(+)CD49b(-) cells had a membrane phenotype similar to i.p. connective tissue-type MC, but were smaller and hypogranular by flow cytometry forward and side scatter profiles, respectively. Consistent with this, they lacked the prominent secretory granules identified by histochemistry and immunodetection for the MC-specific granule proteases that are readily seen in mature jejunal mucosal MC that also are induced by the infection and present at the same time. The concentration of these MC lineage cells in mLN determined by flow cytometry was comparable to that of MC progenitors (MCp) measured by limiting dilution and clonal expansion with maturation. We observed upregulation of IL-4 transcription by MCp in mLN and spleens of helminth-infected 4get mice, and we demonstrated by intracellular cytokine staining production of IL-4 and IL-6 by the mLN MCp in helminth-infected mice. Furthermore, treatment of helminth-infected mice with anti-Fc?RI mAb, a protocol known to deplete basophils, also depleted mLN MCp. Thus, this study identifies a hypogranular subset of MCp recruited to mLN by helminth infection that may be an important unrecognized source of cytokines.
View details for DOI 10.4049/jimmunol.1202567
View details for Web of Science ID 000314825400039
View details for PubMedID 23319739
The Major Genetic Determinants of HIV-1 Control Affect HLA Class I Peptide Presentation
2010; 330 (6010): 1551-1557
Adverse reactions to drugs are increasingly being recognized as important contributions to disease in their own right as well as impediments to the best treatment of various conditions, including infectious, autoimmune, and neoplastic maladies. Rapid drug desensitization (RDD) is an effective mechanism for safely administering important medications while minimizing or entirely circumventing such adverse reactions in sensitized patients. We reviewed the literature on RDD in the last 10 years, including our experience from the Brigham and Women's Hospital Desensitization Program with hundreds of patients desensitized to a broad variety of drugs. RDD in our programme has been uniformly successful in patients with hypersensitivity reactions to antibiotics, chemotherapeutics, and monoclonal antibodies. Any reactions that occur during desensitization are generally much less severe than the initial hypersensitivity reaction to the drug, and patients have received the full dose of the desired medication 99.9% of the time out of (796) desensitizations. To date, there have been no fatalities. RDD is a safe and highly effective method for treating sensitized patients with the optimal pharmacologic agents. Its use should be expanded, but because patient safety is paramount, protocols must be created, reviewed, and overseen by allergist-immunologists with special training and experience in modern techniques of desensitization.
View details for DOI 10.1111/j.1365-2222.2011.03825.x
View details for Web of Science ID 000297283800005
View details for PubMedID 21883538
Clinical problem-solving. A rash hypothesis.
New England journal of medicine
2010; 363 (1): 72-78
Interactive medical case. A rash hypothesis.
New England journal of medicine
2010; 362 (24)
Hodgkin's lymphoma masquerading as vertebral osteomyelitis in a man with diabetes: a case report.
Journal of medical case reports
2010; 4: 102-?
Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.
View details for DOI 10.1126/science.1195271
View details for Web of Science ID 000285153500069
View details for PubMedID 21051598
Brugia malayi microfilariae induce cell death in human dendritic cells, inhibit their ability to make IL-12 and IL-10, and reduce their capacity to activate CD4(+) T cells
JOURNAL OF IMMUNOLOGY
2003; 171 (4): 1950-1960
Infection and malignancy often have common characteristics which render the differential diagnosis for a prolonged fever difficult. Imaging and tissue biopsy are crucial in making a correct diagnosis, though differentiating between chronic osteomyelitis and malignancy is not always straightforward as they possess many overlapping features.A 52-year-old Caucasian man was treated with antibiotics for his diabetic foot infection after a superficial culture showed Staphylococcus aureus. He had persistent fevers for several weeks and later developed acute onset of back pain which was treated with several courses of antibiotics. Radiographic and pathological findings were atypical, and a diagnosis of Hodgkin's lymphoma was made 12 weeks later.Clinicians should maintain a suspicion for Hodgkin's lymphoma or other occult malignancy when features of presumed osteomyelitis are atypical. Chronic vertebral osteomyelitis in particular often lacks features common to acute infectious disease processes, and the chronic lymphocytic infiltrates seen on histopathology have very similar features to Hodgkin's lymphoma, highlighting a similar inflammatory microenvironment sustained by both processes.
View details for DOI 10.1186/1752-1947-4-102
View details for PubMedID 20370895
Parasite Ag-specific T cell unresponsiveness and diminished IFN-gamma production are immunologic hallmarks of patent infection with lymph-dwelling filarial nematodes. Although this diminished responsiveness is directed primarily against the intravascular microfilarial (MF) parasite stage and mediated in part by reduced APC function, the mechanisms involved are not fully understood. In this report, we demonstrate that human dendritic cells (DC) exposed to live MF up-regulate both the cell surface and gene expression of CD54 (ICAM-1). Moreover, live MF result in a 3-fold increase in DC death compared with MF-unexposed DC, primarily due to apoptosis. Notably, microarray and real-time RT-PCR data indicate that live MF concurrently up-regulate mRNA expression of proinflammatory molecules such as IL-8, RANTES, IL-1alpha, TNF-alpha, and IL-beta in DC, the presence of which is also detected at the protein level, while inhibiting the production of IL-12 (p40 and p70) and IL-10. Soluble excretory-secretory products from live MF diminished IL-12 and IL-10 production and induced DC death, although to a lesser degree. Moreover, exposure of DC to live MF resulted in a decrease in the ability of DC to promote CD4(+) T cell production of IFN-gamma and IL-5. Our findings clearly suggest that the interaction between live MF and DC is complex but contributes to the hyporesponsiveness and parasite persistence associated with the MF(+) state in the infected human. These data further suggest that MF induce an orchestrated response in APC that leads to a diminished capacity to function appropriately, which in turn has significant consequences for CD4(+) T cells.
View details for Web of Science ID 000184667400044
View details for PubMedID 12902498