Racial disparities in chronic lymphocytic leukemia/small lymphocytic lymphoma accounting for small molecule inhibitors: A real-world cohort analysis

Kaplan-Meier curve depicting overall survival from CLL treatment start by race. For patients with CLL, no overall survival difference was observed between races in this real-world US database.

First-in-Human Study of the Reversible BTK Inhibitor Nemtabrutinib in Patients with Relapsed/Refractory Chronic Lymphocytic Leukemia and B-Cell Non-Hodgkin Lymphoma

Nemtabrutinib is an orally bioavailable, reversible inhibitor of Bruton tyrosine kinase (BTK) and C481S mutant BTK. We evaluated the safety, pharmacology, and antitumor activity of nemtabrutinib in relapsed/refractory hematologic malignancies. Forty-eight patients with chronic lymphocytic leukemia (CLL), B-cell non-Hodgkin lymphoma (NHL), or Waldenström macroglobulinemia (WM), relapsed/refractory after ≥2 prior therapies were enrolled in the open-label, single-arm, phase I MK-1026-001 study (NCT03162536) to receive nemtabrutinib 5 to 75 mg once daily in 28-day cycles. Dose finding progressed using a 3 + 3 dose escalation design. Primary endpoints were safety and the recommended phase II dose (RP2D). Among 47 treated patients, 29 had CLL, 17 had NHL, and 1 had WM. Grade ≥3 treatment-emergent adverse events occurred in 37 (89%), most commonly neutropenia (11; 23.4%), febrile neutropenia (7; 14.9%), and pneumonia (7; 14.9%). The RP2D was 65 mg daily. An overall response rate of 75% was observed in patients with CLL at 65 mg daily.

SIGNIFICANCE

This first-in-human phase I study demonstrates the safety and preliminary efficacy of nemtabrutinib in patients with relapsed/refractory B-cell malignancies. These data support further exploration of nemtabrutinib in larger clinical studies. This article is featured in Selected Articles from This Issue, p. 5.

Refining prognosis in chronic lymphocytic leukemia with normal Fluorescence in situ hybridization results

Fluorescence in situ hybridization (FISH) to detect the recurrent cytogenetics abnormalities deletion 13q, trisomy 12, deletion 11q, and deletion 17p is important for prognostication in chronic lymphocytic leukemia (CLL). A subset of patients are negative for each of these abnormalities (normal 12/13/11/17 FISH), and outcomes are heterogenous within this group. To elucidate variables important for prognostication in this subgroup we conducted a retrospective analysis of 280 treatment-naïve CLL patients with normal standard CLL FISH results. In a multivariable model, advanced Rai stage (p = 0.04, hazard ratio [HR] 1.24 (95% confidence interval [CI] 1.01-1.53)), unmutated immunoglobulin heavy chain gene (IGHV) (p < 0.0001, HR 5.59 (95% CI 3.63-8.62)) and IGH rearrangement by FISH (p = 0.02, HR 2.56 (95% CI 1.20-5.48)) were significantly associated with shorter time to first treatment. In a multivariable model for overall survival, increasing age at 5-year increments (p < 0.0001, HR 1.55 (95% CI 1.25-1.93)), unmutated IGHV (p = 0.01, HR 5.28 (95% CI 1.52-18.35)) and gain of REL (p = 0.01, HR 4.08 (5% CI 1.45-11.49)) were significantly associated with shorter survival. Our study identifies variables important for refining prognosis for CLL patients with normal standard CLL FISH results.

Synthesis and antibacterial activity of nanoenhanced conjugate of Ag-doped ZnO nanorods with graphene oxide

In this paper, we report a successful synthesis of ZnO nanorods using the microwave-assisted technique, solid-state reaction method was utilized for the preparation of Zn_1-xAg_xO (x = 0.05, 0.1), Hummer's modified method for graphene oxide (GO) along with the sonication method to prepare GO-based Ag-doped ZnO (Zn_1-xAg_xO/GO: x  = 0.05, 0.1) nanocomposites. These nanorods and nanocomposites were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FTIR), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy for structural properties, scanning electron microscopy (SEM) along with energy dispersive X-ray (EDX) spectroscopy for morphological analysis, and UV-Vis spectroscopy for optical properties. XRD, FTIR, and Raman measurements substantiated that each sample is well crystallized in the single-phase polycrystalline wurtzite hexagonal structure of ZnO. The average crystallite size is found to be in decreasing order ranges 40 nm to 29 nm, respectively, along with a significant reduction in the optical bandgap. The SEM images showed a clear evidence of nanorods of ZnO, while the EDX spectra verified the presence of Zn, Ag, O, and C elements in the synthesized samples with their nominal percentage. Furthermore, the prepared nanocomposites effectively inhibited the growth ofStaphylococcus aureus and Escherichia coli. In comparison to pure ZnO nanorods, GO-based Ag-doped ZnO nanorods showed improved antibacterial activity against both S. aureus and E. coli.

Selective suppression of de novo SARS-CoV-2 vaccine antibody responses in patients with cancer on B cell-targeted therapy

We assessed vaccine-induced antibody responses to the SARS-CoV-2 ancestral virus and Omicron variant before and after booster immunization in 57 patients with B cell malignancies. Over one-third of vaccinated patients at the pre-booster time point were seronegative, and these patients were predominantly on active cancer therapies such as anti-CD20 monoclonal antibody. While booster immunization was able to induce detectable antibodies in a small fraction of seronegative patients, the overall booster benefit was disproportionately evident in patients already seropositive and not receiving active therapy. While ancestral virus- and Omicron variant-reactive antibody levels among individual patients were largely concordant, neutralizing antibodies against Omicron tended to be reduced. Interestingly, in all patients, including those unable to generate detectable antibodies against SARS-CoV-2 spike, we observed comparable levels of EBV- and influenza-reactive antibodies, demonstrating that B cell-targeting therapies primarily impair de novo but not preexisting antibody levels. These findings support rationale for vaccination before cancer treatment.

Patient characteristics that predict Richter's transformation in patients with chronic lymphocytic leukemia treated with ibrutinib

Chronic lymphocytic leukemia (CLL) transformation to aggressive lymphoma, known as Richter's Transformation (RT), has a dismal prognosis. There are limited data evaluating risk of RT in patients treated with ibrutinib. We performed a retrospective analysis to determine prognostic variables associated with development of RT and overall survival (OS) at progression after treatment with ibrutinib. We identified 559 patients with CLL treated with ibrutinib from 2010-2019. After a median follow-up of 44.5 months from ibrutinib start, 179 patients progressed and were included in our analysis. After a median follow-up of 20.8 months from progression, 54 out of 179 patients developed RT. Progression on treatment (hazard ratio [HR] 4.01 [1.60-10.00], p = .003), higher LDH (HR 1.80 for 2-fold increase [1.33-2.43], p = .0001), and lymphadenopathy without lymphocytosis (HR 2.88 [1.15-7.20], p = .02) were independent prognostic variables for the development of RT at progression. Progression with lymphadenopathy without lymphocytosis continued to be an independent prognostic variable of worse OS post-progression. In a subset analysis of 50 patients who obtained a PET-CT at progression, the median SUV_max for patients who would develop RT was 15.2 (n = 30, range: 4.0-46.3) versus those patients who did not develop RT with a SUV_max of 7.7 (n = 20, range: 2.3-27.2) (p = .0030). Median OS from date of RT was 4.0 months, suggesting that prognosis for RT remains poor. A lymph node biopsy to rule out RT should be considered in patients who received ibrutinib who progress on treatment, have an elevated LDH, or progress with lymphadenopathy without lymphocytosis.

Consensus opinion from an international group of experts on measurable residual disease in hairy cell leukemia

A significant body of literature has been generated related to the detection of measurable residual disease (MRD) at the time of achieving complete remission (CR) in patients with hairy cell leukemia (HCL). However, due to the indolent nature of the disease as well as reports suggesting long-term survival in patients treated with a single course of a nucleoside analog albeit without evidence of cure, the merits of detection of MRD and attempts to eradicate it have been debated. Studies utilizing novel strategies in the relapse setting have demonstrated the utility of achieving CR with undetectable MRD (uMRD) in prolonging the duration of remission. Several assays including immunohistochemical analysis of bone marrow specimens, multi-parameter flow cytometry and molecular assays to detect the mutant BRAF V600E gene or the consensus primer for the immunoglobulin heavy chain gene (IGH) rearrangement have been utilized with few comparative studies. Here we provide a consensus report on the available data, the potential merits of MRD assessment in the front-line and relapse settings and recommendations on future role of MRD assessment in HCL.

Development of a distributed international patient data registry for hairy cell leukemia

Hairy cell leukemia (HCL) is a rare lymphoproliferative disorder, comprising only 2% of all leukemias. The Hairy Cell Leukemia Foundation (HCLF) has developed a patient data registry to enable investigators to better study the clinical features, treatment outcomes, and complications of patients with HCL. This system utilizes a centralized registry architecture. Patients are enrolled at HCL Centers of Excellence (COE) or via a web-based portal. All data are de-identified, which reduces regulatory burden and increases opportunities for data access and re-use. To date, 579 patients have been enrolled in the registry. Efforts are underway to engage additional COE's to expand access to patients across the globe. This international PDR will enable researchers to study outcomes in HCL in ways not previously possible due to the rarity of the disease and will serve as a platform for future prospective research.

Ventricular arrhythmias and sudden death events following acalabrutinib initiation

Acalabrutinib, a next-generation Bruton's tyrosine kinase inhibitor (BTKi), associates with dramatic efficacy against B-cell malignancies. Recently, unexplained ventricular arrhythmias (VAs) with next-generation BTKi-therapy have been reported. Yet, whether acalabrutinib associates with VAs in long-term follow-up is unknown. Leveraging a large-cohort of 290 consecutive B-cell malignancy patients treated with acalabrutinib from 2014 to 2020, we assessed the incidence of VAs. The primary-endpoint was incident VA development (ventricular fibrillation, ventricular tachycardia, and symptomatic premature ventricular contractions). Probability-scores were assessed to determine likelihood of acalabrutinib-association. Incident rates as function of time-on-therapy were calculated. Weighted average observed incidence rates were compared with expected population rates using relative-risks. Absolute excess risk (AER) for acalabrutinib-associated VAs was estimated. Over 1063 person-years of follow-up, there were 8 cases of incident-VAs, including 6 in those without coronary disease (CAD) or heart failure (HF) and 1 sudden-death; median time-to-event 14.9 months. Among those without prior ibrutinib-use, CAD, or HF, the weighted average incidence was 394 per 100 000 person years compared with a reported incidence of 48.1 among similar-aged non-BTKi-treated subjects (relative risk, 8.2; P < .001; AER, 346). Outside of age, no cardiac or electrocardiographic variables associated with VA development. Collectively, these data suggest VAs may be a class-effect of BTKi therapies.

Patient-driven research: Initial results from a prospective health-related quality of life study performed at the request of patients living with hairy cell leukemia

A diagnosis of leukemia can have a profound effect on patients' health-related quality of life (HRQoL), however this has not been measured prospectively in patients with hairy cell leukemia (HCL). At the request of patients living with HCL who had identified this gap in knowledge about the disease, we conducted a longitudinal study of HRQoL among patients enrolled in the HCL Patient Data Registry (PDR). From September 1, 2018 to September 1, 2020, 165 patients were enrolled in the study and completed the baseline survey. The Functional Assessment of Cancer Therapy - Leukemia (FACT-Leu) was used to measure patients' HRQoL. Results show that newly diagnosed HCL patients reported the lowest HRQoL, followed by patients in relapse and those on "watch and wait." Factors associated with higher (better) FACT-Leu total scores in the multivariable analysis included older age, higher social support, and greater physical activity. These same factors were associated with lower levels of fatigue. In rare diseases where it is difficult to perform large prospective studies, patient/researcher collaborations are critical for the identification of studies that are of importance to patients and their families in order to maximize the benefits of the research and improve the lives of patients living with HCL.

Hypertension and incident cardiovascular events after next-generation BTKi therapy initiation

BACKGROUND

Post-market analyses revealed unanticipated links between first-generation Bruton's tyrosine kinase inhibitor (BTKi) therapy, ibrutinib, and profound early hypertension. Yet, whether this is seen with novel selective second (next)-generation BTKi therapy, acalabrutinib, is unknown.

METHODS

Leveraging a large cohort of consecutive B cell cancer patients treated with acalabrutinib from 2014 to 2020, we assessed the incidence and ramifications of new or worsened hypertension [systolic blood pressure (SBP) ≥ 130 mmHg] after acalabrutinib initiation. Secondary endpoints were major cardiovascular events (MACE: arrhythmias, myocardial infarction, stroke, heart failure, cardiac death) and disease progression. Observed incident hypertension rates were compared to Framingham heart-predicted and ibrutinib-related rates. Multivariable regression and survival analysis were used to define factors associated with new/worsened hypertension and MACE, and the relationship between early SBP increase and MACE risk. Further, the effect of standard antihypertensive classes on the prevention of acalabrutinib-related hypertension was assessed.

RESULTS

Overall, from 280 acalabrutinib-treated patients, 48.9% developed new/worsened hypertension over a median of 41 months. The cumulative incidence of new hypertension by 1 year was 53.9%, including 1.7% with high-grade (≥ 3) hypertension. Applying the JNC 8 cutoff BP of ≥ 140/90 mmHg, the observed new hypertension rate was 20.5% at 1 year, > eightfold higher than the Framingham-predicted rate of 2.4% (RR 8.5, P < 0.001), yet 34.1% lower than ibrutinib (12.9 observed-to-expected ratio, P < 0.001). In multivariable regression, prior arrhythmias and Black ancestry were associated with new hypertension (HR 1.63, HR 4.35, P < 0.05). The degree of SBP rise within 1 year of treatment initiation predicted MACE risk (42% HR increase for each + 5 mmHg SBP rise, P < 0.001). No single antihypertensive class prevented worsened acalabrutinib-related hypertension.

CONCLUSIONS

Collectively, these data suggest that hypertension may be a class effect of BTKi therapies and precedes major cardiotoxic events.

Optimizing extracellular vesicles' isolation from chronic lymphocytic leukemia patient plasma and cell line supernatant

In chronic lymphocytic leukemia (CLL) and very likely all cancer types, extracellular vesicles (EVs) are a common mechanism by which intercellular messages are communicated between normal, diseased, and transformed cells. Studies of EVs in CLL and other cancers have great variability and often lack reproducibility. For CLL patient plasma and cell lines, we sought to characterize current approaches used in isolating EV products and understand whether cell culture-conditioned media or complex biological fluids confound results. Utilizing nanoparticle tracking analysis, protein quantification, and electron microscopy, we show that ultracentrifugation with an OptiPrep cushion can effectively minimize contaminants from starting materials including plasma and conditioned media of CLL cell lines grown in EV-depleted complete RPMI media but not grown in the serum-free media AIM V commonly used in CLL experimental work. Moreover, we confirm the benefit of including 25 mM trehalose in PBS during EV isolation steps to reduce EV aggregation, to preserve function for downstream applications and characterization. Furthermore, we report the highest particles/μg EVs were obtained from our CLL cell lines utilizing the CELLine bioreactor flask. Finally, we optimized a proliferation assay that offers a functional evaluation of our EVs with minimal sample requirements.

Phase II Study of Combination Obinutuzumab, Ibrutinib, and Venetoclax in Treatment-Naïve and Relapsed or Refractory Chronic Lymphocytic Leukemia

PURPOSE

The development of highly effective targeted agents for chronic lymphocytic leukemia offers the potential for fixed-duration combinations that achieve deep remissions without cytotoxic chemotherapy.

PATIENTS AND METHODS

This phase II study tested a combination regimen of obinutuzumab, ibrutinib, and venetoclax for a total of 14 cycles in both patients with treatment-naïve (n = 25) and relapsed or refractory (n = 25) chronic lymphocytic leukemia to determine the response to therapy and safety.

RESULTS

The primary end point was the rate of complete remission with undetectable minimal residual disease by flow cytometry in both the blood and bone marrow 2 months after completion of treatment, which was 28% in both groups. The overall response rate at that time was 84% in treatment-naïve patients and 88% in relapsed or refractory patients. At that time, 67% of treatment-naïve patients and 50% of relapsed or refractory patients had undetectable minimal residual disease in both the blood and marrow. At a median follow-up of 24.2 months in treatment-naïve patients and 21.5 months in relapsed or refractory patients, the median progression-free and overall survival times were not yet reached, with only 1 patient experiencing progression and 1 death. Neutropenia and thrombocytopenia were the most frequent adverse events, followed by hypertension. Grade 3 or 4 neutropenia was experienced by 66% of patients, with more events in the relapsed or refractory cohort. There was only 1 episode of neutropenic fever. A favorable impact on both perceived and objective cognitive performance during treatment was observed.

CONCLUSION

The combination regimen of obinutuzumab, ibrutinib, and venetoclax offers time-limited treatment that results in deep remissions and is now being studied in phase III cooperative group trials.

Second cancer incidence in CLL patients receiving BTK inhibitors

Chronic lymphocytic leukemia (CLL) is associated with perturbed immune function and increased risk for second primary malignancies (SPM). Ibrutinib and acalabrutinib (BTKi) are effective therapies for CLL resulting in partial restoration of immune function. The incidence of and risk factors for SPM in CLL patients receiving BTKi are not yet characterized. We retrospectively determined the incidence of SPM in CLL patients treated with ibrutinib or acalabrutinib at our institution between 2009 and 2017, assessed for association between baseline characteristics and SPM incidence, and compared the observed to expected cancer incidence among age, sex, and year matched controls without CLL. After a median of 44 months follow-up, 64/691 patients (9%) were diagnosed with SPM (excluding non-melanoma skin cancer [NMSC]). The three-year cumulative incidence rate was 16% for NMSC and 7% for other SPM. On multivariable analysis, smoking was associated with increased SPM risk (HR 2.8 [95% CI: 1.6–4.8]) and higher baseline CD8 count was associated with lower SPM risk (HR 0.9 for 2-fold increase [95% CI: 0.8–0.9]). The observed over expected rate of SPM was 2.2 [95% CI: 1.7–2.9]. CLL patients treated with BTKi remain at increased risk for SPM, and secondary cancer detection is an important consideration in this population.

Acalabrutinib plus Obinutuzumab in Treatment-Naïve and Relapsed/Refractory Chronic Lymphocytic Leukemia

Acalabrutinib is a selective irreversible Bruton tyrosine kinase (BTK) inhibitor that does not affect IL2-associated tyrosine kinase or antibody-dependent cellular cytotoxicity, making it an attractive candidate for combination therapy with anti-CD20 antibodies. We investigated acalabrutinib plus obinutuzumab in a phase Ib/II study (NCT02296918) of patients with treatment-naïve or relapsed/refractory chronic lymphocytic leukemia (CLL). Nineteen treatment-naïve and 26 relapsed/refractory patients were treated with acalabrutinib (100 mg twice daily) until progression and obinutuzumab (cycle 1: 100 mg day 1, 900 mg day 2, 1000 mg days 8 and 15; cycles 2-6: 1,000 mg day 1). Grade 3/4 adverse events occurred in 71% of patients. Overall response rates were 95% (treatment-naïve) and 92% (relapsed/refractory). Thirty-two percent of treatment-naïve and 8% of relapsed/refractory patients achieved complete remission. At 36 months, 94% (treatment-naïve) and 88% (relapsed/refractory) were progression free. Acalabrutinib plus obinutuzumab was well tolerated, producing high and durable responses in treatment-naïve and relapsed/refractory CLL. SIGNIFICANCE: Rituximab plus the less selective BTK inhibitor ibrutinib has not shown benefit in CLL; however, the selective BTK inhibitor acalabrutinib plus the antibody-dependent cellular cytotoxicity-enhanced antibody obinutuzumab yielded durable responses that deepened over time in treatment-naïve and relapsed/refractory CLL, supporting the evaluation of this approach in larger, comparative studies in CLL.This article is highlighted in the In This Issue feature, p. 327.

A Phase II Trial of Rituximab Combined With Pegfilgrastim in Patients With Indolent B-cell Non-Hodgkin Lymphoma

BACKGROUND

To explore the role of augmenting neutrophil function in B-cell lymphoma, we conducted a phase II study evaluating the safety and clinical efficacy of pegfilgrastim and rituximab in low-grade CD20⁺ B-cell non-Hodgkin lymphoma (B-NHL).

PATIENTS AND METHODS

Twenty patients with indolent B-NHL were treated with rituximab (375 mg/m²) every other week for 4 doses, followed by every 2 months for 4 additional doses. Pegfilgrastim was administered subcutaneously 3 days before each dose of rituximab. Clinical activity and tolerability were assessed using standard criteria. Biologic monitoring included phenotype characteristics of the host neutrophils, changes in oxidative burst, and functional assays.

RESULTS

The patient demographics included median age of 64 years, 70% were male, 70% had follicular lymphoma, and 90% had stage III-IV disease. The median number of previous therapies was 2 (range, 0-5); 90% had received previous anti-CD20 monoclonal antibody therapy. The addition of pegfilgrastim to rituximab did not increase rituximab-related toxicities. The overall response rate was 60% (12 of 20), with a complete response (CR) rate of 35% (7 of 20). The median progression-free survival (PFS) duration was 17.9 months (95% confidence interval, 9.9-27.6 months); the median overall survival was not reached. A shorter time-to-peak oxidative burst after the first dose of pegfilgrastim was associated with greater CR rates (P = .04) and longer PFS (P = .03).

CONCLUSION

The pegfilgrastim-rituximab combination was well tolerated, with favorable outcomes compared with historical controls. A shorter time-to-peak oxidative burst was associated with higher CR rates and longer PFS. Our results support further evaluation of strategies that enhance the innate immune system to improve rituximab activity in B-NHL.

Molecular prevalence of Babesia bigemina in Rhipicephalus microplus ticks infesting cross-bred cattle of Punjab, India

Babesiosis is an economically important tick-borne apicomplexan protozoan disease of cattle in tropical and subtropical regions. In the present study, Rhipicephalus microplus engorged female ticks were collected from 135 apparently healthy cattle from different agro-climatic zones of Punjab, India, to investigate the carrier status of Babesia bigemina infection in vector tick by using microscopy and PCR based assays. PCR when applied on DNA extracted from the egg masses harvested from ticks showed 1.48% (2/135) samples as positive, whereas 4.44% (6/135) samples were positive when product of primary PCR was used as template in nPCR. Further, among the DNA samples isolated from the unfed larval stages that emerged from egg masses laid by ticks, only 1.48% (2/135) samples were detected as positive for B. bigemina in PCR, while 7.41% (10/135) samples were detected positive in nPCR assay. Statistically, non-significant (p > 0.05) difference in prevalence rates was observed across different agro-climatic zones and between different age groups of cattle from which engorged ticks were collected. It can, thus, be concluded that prevalence of B. bigemina in the vector tick, R. microplus in Punjab state of India indicates an endemic status of the organism and a further study is needed for the management and control of the bovine babesiosis.

Molecular detection of Babesia bigemina infection in apparently healthy cattle of central plain zone of Punjab

Bovine babesiosis is an important tick-borne disease caused by the parasites belonging to the genus Babesia, distributed worldwide and infecting a wide range of domesticated and wild cattle, occasionally man. The present study was conducted to determine the prevalence of B. bigemina infection in apparently healthy cattle from central plain zone of Punjab, India. Examination of Giemsa-stained peripheral thin blood smears revealed 2.45 % (5/204) animals to be positive for piroplasms of B. bigemina. However, genomic DNA isolated from these blood samples when subjected to primary PCR revealed a positivity of 7.35 % (15/204) as detected by the amplification of a 278-bp product in the agarose gel. PCR products obtained from the primary PCR of B. bigemina, when employed as template in nested PCR produced the amplicons of desired size (170 bp) was detected in 30.39 % (62/204) of the samples. It can thus be concluded that B. bigemina infection is prevalent in apparently healthy cattle population of this region and PCR assays can serve as a valuable tool for epidemiological studies in endemic areas.

Coprological investigation on neonatal bovine cryptosporidiosis in Ludhiana, Punjab

An overall prevalence of 38.90 % was recorded for bovine cryptosporidiosis on coprological examination of 144 faecal samples collected from neonatal cattle calves from organised dairy farms in and around Ludhiana, Punjab by modified Ziehl-Neelsen staining. Further, a gradual decline in the percent prevalence was seen with increase in the age of the host from <1 month (64.1 %) to 4-5 months (12.5 %). The highest prevalence was recorded during the monsoon season (47.06 %) followed by summer (37.73 %) and winter (30.0 %) season and the seasonal variation was statistically significant (p ≤ 0.05). Female calves showed higher prevalence (44.32 %) than their male counterparts (27.66 %). Further, prevalence of cryptosporidiosis was significantly higher (p ≤ 0.05) in the diarrhoeic calves (52.70 %) as compared to the non-diarrhoeic (24.28 %) thus indicating a relatively higher risk (1.75 times) of the disease in diarrhoeic than normal calves.

Comparison of nested PCR and microscopy for the detection of cryptosporidiosis in bovine calves

The comparative efficacies of different conventional parasitological methods and nested PCR for diagnosis of bovine cryptosporidiosis in faecal samples were evaluated. Among the 100 samples collected from calves in and around Ludhiana Direct faecal smear staining technique revealed 25.0 % positivity for the oocysts of Cryptosporidium spp. with sensitivity and specificity of 68.12 and 92.98 %, respectively. Zinc sulphate solution floatation and saturated sugar solution floatation staining techniques showed sensitivity and specificity of 83.92 and 96.36; 81.03 and 98.14 %, respectively. Products of the primary PCR of Cryptosporidium spp. directed against small subunit (18S) ribosomal RNA when employed as template in nested PCR produced the amplicons of desired size (834 bp) in 47.0 % of the samples. Amplification of 834 bp fragment was also observed in positive control, while no amplification was observed in negative control. Results indicated PCR assays as highly sensitive and specific techniques for the screening of the samples for Cryptosporidium spp. but in developing countries and under field conditions where limited resources do not allow the application of PCR assays, concentration staining methods are recommended.

Novel antibodies in the treatment of non-Hodgkin's lymphoma

Monoclonal antibodies (mAbs) have revolutionised the treatment of malignancies, especially non-Hodgkin's lymphoma (NHL). Antibody-based therapies target tumour cells expressing a specific antigen while sparing the majority of normal cells leading to a decrease in treatment-associated toxicity. Rituximab, a monoclonal antibody directed against CD20 on B cells, was the first monoclonal antibody to be approved by the US Food and Drug Association (FDA) in 1997 for the treatment of patients with relapsed/refractory, follicular or low-grade NHL . However, it was soon realised that not all patients respond to rituximab therapy and close to 60% of patients with follicular lymphoma who were previously sensitive to rituximab become 'resistant' to repeat rituximab therapy. This led to further attempts to improve the antitumour activity of anti-CD20 mAbs (i.e. 2nd/3rd generation anti-CD20s), and to identify additional potential targets on lymphoma cells other than CD20. A number of these antibodies directed against lymphoma cell targets other than CD20 are now undergoing development, many of which are currently in clinical trials. This manuscript focuses on an overview of these 'non-anti-CD20' novel mAbs for NHL.