Correlates of resistance to HIV-1 infection in homosexual men with high-risk sexual behaviour

OBJECTIVE: To investigate possible correlates of HIV resistance in participants from the Amsterdam Cohort of Homosexual men who have remained HIV seronegative despite high-risk sexual behaviour. DESIGN/METHODS: We studied in vitro HIV-1 susceptibility and adaptive and innate immunity in 29 high-risk seronegative (HRSN) and 15 HIV-negative pre-seroconversion (pre-SC) homosexual men from the same Amsterdam Cohort Study (ACS) who seroconverted to HIV-1 positive during active follow-up. Host genetics were compared between HRSN and HIV-positive ACS participants. RESULTS: We found lower in vitro susceptibility for a CCR5-using (R5) HIV-1 variant, higher RANTES production levels, but no difference in coreceptor expression in HRSN as compared with pre-SC controls. Reduced R5 in vitro susceptibility of two HRSN tested was restored to normal levels by addition of antibodies against beta-chemokines. A higher proportion of HRSN carried the SDF-1 3'A variant and HLA-A*11, A*31 and Cw*15 alleles. ELIspot analysis with HIV-1 peptide stimulation revealed low frequencies of HIV-1-specific CD8 interferon-gamma producing cytotoxic T cells in both HRSN and pre-SC controls. CONCLUSIONS: Low in vitro R5 susceptibility of cells from the HRSN men was due to beta-chemokine mediated inhibition of virus replication. The presence of HIV-1 specific cytotoxic T cells in both HRSN and pre-SC participants may signify exposure to the virus rather than protection from infection. Host genetic characteristics and other factors affecting innate immunity may contribute to differential resistance to HIV-1 infection among exposed seronegative individuals.     

The effect of prophylactic calcium and magnesium infusions on the incidence of neurotoxicity and clinical outcome of oxaliplatin-based systemic treatment in advanced colorectal cancer patients

Background

Peripheral sensory neurotoxicity is a frequent and potentially debilitating side effect of oxaliplatin treatment. Calcium and magnesium (Ca/Mg) infusions are frequently used to prevent this toxicity. However, concerns about a negative impact of Ca/Mg infusions on outcome have been raised. We retrospectively assessed the effect of Ca/Mg infusions on the incidence of neurotoxicity and on clinical outcome in advanced colorectal cancer (ACC) patients treated in the phase III CAIRO2 study.

Materials and methods

Seven hundred and fifty five previously untreated ACC patients were randomised between treatment with capecitabine, oxaliplatin and bevacizumab or the same combination with the addition of cetuximab. Patients were retrospectively divided into two groups: patients in the Ca/Mg⁺ group received Ca/Mg at least during their first treatment cycle, and patients in the Ca/Mg^- group did not.

Results

Seven hundred and thirty two patients were evaluable for this analysis. The Ca/Mg⁺ group consisted of 551 patients, the Ca/Mg^- group consisted of 181 patients. The incidence of all grade neurotoxicity in the Ca/Mg⁺ group and the Ca/Mg^- group was 85% and 92%, respectively (p = 0.02), and the incidence of grade ? 2 neurotoxicity was 40% and 45%, respectively (p = 0.22). The median PFS in the Ca/Mg⁺ versus Ca/Mg^- group was 10.1 versus 10.7 months (p = 0.92), the median OS was 19.8 versus 20.7 months (p = 0.10), and the response rate was 43.1% versus 50% (p = 0.11), respectively.

Conclusions

In this largest retrospective analysis to date we observed that Ca/Mg infusions significantly reduced all grade oxaliplatin-related neurotoxicity. Ca/Mg infusions did not affect the clinical efficacy of treatment.     

Decreasing sensitivity to RANTES (regulated on activation,normally T cell-expressed and -secreted) neutralization of CC chemokine receptor 5-using,non-syncytium-inducing virus variants in the course of human immunodeficiency virus type 1 infection

In approximately half of human immunodeficiency virus (HIV) type 1-infected individuals, the development of CXC chemokine receptor 4-using, syncytium-inducing (SI) virus variants precedes a rapid progression to acquired immunodeficiency syndrome (AIDS). In other individuals, only CC chemokine receptor 5-using (R5), non-SI (NSI) virus variants are present throughout infection. These individuals may be either long-term survivors (LTSs) or rapid progressors. The basis for this variable disease progression in individuals with only R5 virus variants is not yet fully understood. In this study, the beta-chemokine sensitivity of biological HIV-1 clones isolated from 13 individuals who harbored only R5, NSI virus variants (7 LTSs and 6 progressors) was investigated. We found a statistically significant decrease in sensitivity of virus variants to RANTES (regulated on activation, normally T cell-expressed and -secreted) neutralization during the course of progressive infection, but not during follow-up of LTSs. Our data suggest that a role exists for RANTES neutralization sensitivity of HIV-1 in AIDS pathogenesis.     

Immunotherapeutic effects of local chemotherapy with an active metabolite of cyclophosphamide

A new approach is described for the use of cytostatic drugs as biological response modifiers (BRM's). Under restricted conditions, strong potentiation of T-effector function can be obtained through preferential elimination of suppressor cells. Recent studies from our group have demonstrated that such conditions are fulfilled when low dosages of certain drugs are injected at a site of low antigenic stimulation. Furthermore, local injection of cytostatic drugs not only enhances the development of cell-mediated immunity in non-sensitized animals, but also facilitates the reversal of existing immunological tolerance. These data shed new light on the tumor regression and induction of tumor immunity observed upon intralesional chemotherapy in experimental tumor models.     

European vs 2015-World Health Organization clinical molecular and pathological classification of myeloproliferative neoplasms

The BCR/ABL fusion gene or the Ph~1-chromosome in the t(9;22)(q34;q11)exerts a high tyrokinase acticity,which is the cause of chronic myeloid leukemia(CML).The1990 Hannover Bone Marrow Classification separated CML from the myeloproliferative disorders essential thrombocythemia(ET),polycythemia vera(PV)and chronic megakaryocytic granulocytic myeloproliferation(CMGM).The 2006-2008 European Clinical Molecular and Pathological(ECMP)criteria discovered 3variants of thrombocythemia:ET with features of PV(prodromal PV),"true"ET and ET associated with CMGM.The 2008 World Health Organization(WHO)-ECMP and 2014 WHO-CMP classifications defined three phenotypes of JAK2~(V617F)mutated ET:normocellular ET(WHO-ET),hypercelluar ET due to increased erythropoiesis(prodromal PV)and ET with hypercellular megakaryocytic-granulocytic myeloproliferation.The JAK2~(V617F)mutation load in heterozygous WHO-ET is low and associated with normal life expectance.The hetero/homozygous JAK2~(V617F)mutation load in PV and myelofibrosis is related to myeloproliferative neoplasm(MPN)disease burden in terms of symptomaticsplenomegaly,constitutional symptoms,bone marrow hypercellularity and myelofibrosis.JAK2 exon 12mutated MPN presents as idiopathic eryhrocythemia and early stage PV.According to 2014 WHO-CMP criteria JAK2 wild type MPL~(515)mutated ET is the second distinct thrombocythemia featured by clustered giant megakaryocytes with hyperlobulated stag-horn-like nuclei,in a normocellular bone marrow consistent with the diagnosis of"true"ET.JAK2/MPL wild type,calreticulin mutated hypercellular ET appears to be the third distinct thrombocythemia characterized by clustered larged immature dysmorphic megakaryocytes and bulky(bulbous)hyperchromatic nuclei consistent with CMGM or primary megakaryocytic granulocytic myeloproliferation.     

Tumor regression and induction of anti-tumor immunity by local chemotherapy of guinea-pigs bearing a line-10 hepatocarcinoma

Local administration of a low dosage of the active cyclophosphamide derivative 4-hydroperoxy-cyclophosphamide (4-HPCY) at the site of antigenic stimulation strongly enhances T-cell-mediated immune responses in both mice and guinea-pigs. Such immunopotentiation is related to functional elimination of suppressor cells from the draining lymph nodes. In the present study we examined the potential immunotherapeutic effects of local cytostatic drug administration in strain-2 guinea-pigs bearing a line-10 hepatocarcinoma. This tumor, when injected intradermally (10(6) cells) metastasizes within 7 days into the draining lymph node and untreated animals die within 60-80 days from metastatic growth. In sensitization experiments, using irradiated line-10 tumor cells, potentiation of delayed-type hypersensitivity reactivity was observed with local administration of low dosages of 4-HPCY. Intralesional treatment with increasing dosages of 4-HPCY, when started 7 days after tumor-cell inoculation and continued for 3 weeks, resulted in a dose-dependent regression of the primary tumor. Cure rates of up to 75% were achieved. All cured animals showed strong delayed-type hypersensitivity reactivity towards line-10 cells and were resistant to a rechallenge with 10(6) line-10 tumor cells. When treatment was started at a very late stage of the disease (day 14) only a small number of animals were cured. However, when local chemotherapy was preceded by one (non-curative) systemic dose of cyclophosphamide, a 57% cure rate was obtained. Again, all cured animals showed strong delayed-type hypersensitivity reactivity and protective immunity to line-10 tumor cells. Tumor immunity was transferable to naive recipients with immune spleen cells and was T-cell-dependent. Other cytostatic drugs, selected for local immunopotentiating capacity, notably etoposide (VP16) and cis-platinum (cis-Pt) were similarly effective in the local chemotherapy protocol.     

Natural controlled HIV infection: preserved HIV-specific immunity despite undetectable replication competent virus

Long-term non-progressive HIV infection, characterized by low but detectable viral load and stable CD4 counts in the absence of antiviral therapy, is observed in about 5% of HIV-infected patients. Here we identified four therapy na?ve individuals who are strongly seropositive for HIV-1 but who lack evidence of detectable HIV p24 antigen, plasma RNA, and proviral DNA in routine diagnostic testing. With an ultrasensitive PCR, we established that frequencies of pol proviral DNA sequences were as low as 0.2-0.5 copies/10(6) PBMC. HIV could not be isolated using up to 30x10(6) patient PBMC. One individual was heterozygous for CCR5 Delta32, but CCR5 expression on CD4+ T cells was normal to high in all four individuals. In vitro R5 and X4 HIV-1 susceptibility of CD8-depleted PBMC of all study subjects was significantly lower than the susceptibility of CD8-depleted PBMC of healthy blood donors. All individuals expressed protective HLA-B*58s alleles and showed evidence of HIV-specific cellular immunity either by staining with HLA-B*57 tetramers folded with an HIV RT or gag peptide or after stimulation with HIV-1 p24 gag, RT, or nef peptides in ELIspot analysis. HIV-specific CD4+ T helper cells were demonstrated by proliferation of CD4+ T cells and intracellular staining for IL-2 and IFNgamma after stimulation with an HIV-gag peptide pool. Sera of all individuals showed antibody-mediated neutralization of both R5 and X4 HIV-1 variants. These data implicate that very low-level antigen exposure is sufficient for sustained HIV-specific immunity and suggest the possibility of a multi-factorial control of HIV infection.     

The epidermal phenotype during initiation of the psoriatic lesion in the symptomless margin of relapsing psoriasis

Background: The mature psoriatic lesion does not necessarily demonstrate changes relevant to early phases of the lesion. Objective: In a model for relapsing psoriasis we examined the epidermal phenotype by means of a panel of immunohistochemical parameters: keratins 14 and 16, epidermal growth factor receptor (EGFR), Ki-67 antigen, and Tdt-mediated Unscheduled Nick End Labeling to detect apoptosis. Methods: In 9 patients, we cleared psoriatic plaques by topical treatment with clobetasol-17-propionate under hydrocolloid occlusion. Relapse (defined as a clinical sum score ≥ 6) was awaited. Biopsy specimens of the psoriatic lesion, the cleared skin, the relapsed plaque, and its clinically normal margin were assessed. Results: Psoriasis recurred after 19 ± 6 weeks (mean ± SEM). During treatment all parameters improved considerably; however, the number of apoptotic cells was not affected.Ki-67 values decreased well below the normal range. At initial relapse, the symptomless skin adjacent to the relapsing lesion (margin) showed a marked expression of keratin 16 and EGFR. Ki-67 expression was increasing in the margin but was below values of the mature lesion. The localization of cycling cells in the first suprabasal layers was a remarkable feature. Keratin 14 expression was increased in the recurrent lesion itself, but not in the symptomless margin. Conclusion: Keratin 16 and EGFR expression are early phenomena in the evolution of the lesion, and they anticipate epidermal proliferation. The expression of keratin 14 follows overt epidermal hyperproliferation. The present observation in incipient psoriasis lends support to the hypothesis that the basal cell compartment does not have a primary involvement in the initiation of epidermal abnormalities in psoriasis, but that a coordinated sequence of events involving proliferation and differentiation markers in the first suprabasal layers of the epidermis could be the key to the pathogenesis of this puzzling disease. (J Am Acad Dermatol 1999;40:901-9.)     

Evaluation of gastroesophageal function and mechanisms underlying gastroesophageal reflux in infants and adults born with esophageal atresia

Purpose

To evaluate the mechanisms underlying gastroesophageal reflux (GER) following esophageal atresia (EA) repair and gastroesophageal function in infants and adults born with EA.

Methods

Ten consecutive infants born with EA as well as 10 randomly selected adult EA patients were studied during their first postoperative follow-up visit and a purposely planned visit, respectively. A ¹³C-octanoate breath test and esophageal pH–impedance–manometry study were performed. Mechanisms underlying GER and esophageal function were evaluated.

Results

Transient lower esophageal sphincter relaxation (TLESR) was the most common mechanism underlying GER in infants and adults (66% and 62%, respectively). In 66% of all GER episodes, no clearing mechanism was initiated. On EFT, normal motility patterns were seen in six patients (four infants, two adults). One of these adults had normal motility overall (> 80% of swallows). Most swallows (78.8%) were accompanied by abnormal motility patterns. Despite this observation, impedance showed normal bolus transit in 40.9% of swallows. Gastric emptying was delayed in 57.1% of infants and 22.2% of adults.

Conclusions

TLESR is the main mechanism underlying GER events in patients with EA. Most infants and adults have impaired motility, delayed bolus clearance, and delayed gastric emptying. However, normal motility patterns were seen in a minority of patients.